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[P]
Catch a Wave: Profitable Alternative Energy?

By imrdkl in Technology
Wed Mar 05, 2003 at 12:42:16 PM EST
Tags: Focus On... (all tags)
Focus On...

Recent events have generated new interest in alternative energy. Even the Bush Administration has recently released an extensive new estimate of the potential for alternative energy in the US, calling it the "fastest growing segment of the industry". Indeed, interest is piquing around the world. But in spite of all the good press, until alternative energy can compete heads-up with conventional power, a distinct skepticism will likely remain.

There is one alternative source however, which has potential up to a thousand times higher than the others. Ocean wave power, according to the noted UK environmentalist, David J. Bellamy, "could produce the baseload of electricity for most maritime nations." Indeed, wave power could produce up to 16% of the world's needs, in the future. Unfortunately, harvesting wave power is a tricky business. Over the last few decades, millions have been spent by researchers (and their sponsors) in the UK, Australia, Norway, and many other countries in the process of developing wave power technology - without much real success.

Now it seems as though an American company might be the first to get rich from wave power.


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Decades of research leaves few contenders

Researchers have been studying wave power for decades, and slowly learning which concepts work best. There are now more than 1000 patents held worldwide related to wave power, although there are very few commercial wave power generating stations which actually put electricity on the grid. Todays technology, while quite diverse, is primarily based on one of three designs, each of which have been around for some time:

  • Oscillating Water Column (OWC) - An OWC is a large structure which is conventionally built on the shoreline. The early designs were monolithic, but the latest plans call for pre-fabricated units, made of easily-replaceable sections. The OWC traps the incoming wave, and forces it into a narrow chamber (pipe). The resulting air pressure above the water in the pipe drives a Wells Turbine. Wells Turbines are designed to allow air to pass through in both directions, while spinning in the same direction, thus harvesting power from both the incoming pressure, and the outgoing suction created in the chamber by the wave. While OWC technology is well tested and fairly reliable, it requires extensive modification of the shoreline to install the structure, and it is not as efficient as other devices which harvest wave power offshore - although recent optimizations of the wave chamber have been encouraging.

    The UK has spent the most time and money researching and developing OWC wave power. Recently the leading producer of OWC devices there was awarded 2.1m to test a new prototype, in fact. An interesting hybrid OWC station which is deployed offshore is called the Mighty Whale, which produces power for Japan.

  • The Flapper - The "flapper" is one of two primary designs which are deployed offshore using pontoons or buoys. Flapper devices go under several different names, Salter Duck, Clam, and others. Typically, these devices consist of a string of floating pontoons which are shaped a bit like a camshaft. Each pontoon is essentially a cam, which flaps, or rotates partially, from the wave passing over it. This flapping effect drives capillary pumps, sending liquid through a common hose, and eventually to a turbine which converts the liquid pressure to electricity. These wave-power devices are conventionally deployed perpendicular to the incoming wave force. Because of that, flappers are particularly susceptible to heavy seas and storms.

    A newer, and very promising innovation on the arrayed pontoon configuration looks something like a "snake" of pontoons which are deployed parallel to the wave force. This device, called the Pelamis (after the sea-snake), achieves its pumping action via the "slithering" of the pontoons as the wave passes beneath each section on it's way to the shore. The Pelamis seems to hold promise, especially as a supplemental power source for offshore consumers such as oil rigs, but it's potential is limited by it's pumping capacity and the waves height.

  • Heaving buoy-Pump - the heaving buoy-pump design sets out large buoys offshore which, through their heaving (bobbing) motion, drive an underwater piston and pump assembly attached to the buoy via a long cable or rod. As with the flapper devices, the resulting hydraulic fluid pressure is converted to electricity. Typically, a large structure anchored to the ocean floor (mpeg) houses the piston and pump assembly as well as the converter and generator.

    There are many variants on the basic buoy-pump design - with differences in the form and location of the piston, the type of pump, and the size and shape of the buoy, just to name a few. According to Bellamy and others, the buoy-pump design seems to hold the most promise for the future of wave power - but the buoy-pump design is not without its own set problems. Like other offshore devices, they're subject to bad weather, albeit not to the extent of the flapper or snake design. They typically also require heavy underwater moorings - and a lot of "deep water work" to install.

Heaving Buoys - a closer look

As mentioned at the beginning of this article, an American company now has an implementation of the buoy-pump design that they claim can overcome some of the difficulties. In fact, the company claims that their device can produce power in the 3-4 cents/kwh range - that's the threshold price at where wave power can compete with conventional power prices. Before we take a look at this new contender, let's have a closer look at how the buoy-pump device actually works, and find out something about the challenge to make it efficient.

Possibly the most difficult challenge for a buoy-pump wave-power station is meeting the wave itself. Optimizing a buoy-pump device for various conditions is a tricky business. A good buoy-pump must be able to accomodate varying wave height and frequency to effectively and efficiently drive a pump. The buoy must maximize lift, without exceeding the length of the piston shaft which is driving the pump beneath. If the wave is too high, the piston must be protected from excessive lift. Not to mention corrosion and rust.

The piston/pump assemblies are complex as well. They're typically built with a heavy spring and/or counterweight to return the piston to the "down" position after being lifted by the wave. The "downstroke" has to be timed as closely as possible to follow the form of the "back" of the wave, in order to minimize drag. Theoretically, the piston and its buoy should achieve a state of resonance. In practice, this is accomplished through the use of various valving and latching techniques which are also built into the piston and pump, along with the spring and counterweight.

The buoy pump system is typically deployed about a kilometer offshore, but is naturally dependent on observation and testing to determine the best location. Depth is an important factor, as well as the undersea geology. The most common designs have their pump, piston, and generator workings located in a structure which is moored directly to the sea bottom, with the buoy attached via cable or rod. Depth is therefore an important factor for maintenance, as well as initial installation costs. Naturally, a deployment location also must be closed off to shipping and recreational boating, although the buoys are typically grouped within a specific (limited) area.

Building a better wave trap

So, that's all very nice, but what about the grand allusion at the beginning of the article? Has someone really built a better wave-trap? I'm still leaning towards a definite "maybe" on that question, but let's have a closer look.

Ocean Power Technologies (OPT) was founded in 1994 by George Taylor an electrical engineer from Australia. Taylor and co-founder Joseph Burns worked with US Navy during the late 80's, to develop piezoelectric streamers, which collect energy passively from the wave's motion. During the early 90's, they turned their focus to buoy-pump devices. But they weren't the only ones who were looking hard at buoy-pumps at that time. In Norway, for example, at the Wave Power Research Division of the Norwegian University of Science and Technology (NTNU), a good deal of research was reaching the "note" stage. The scientists there were considering things like phase control and optimum oscillation, and discussing the necessity for predicting oncoming wave amplitudes to help optimize the piston stroke as early as 1993. The buoy-pump concept was definitely catching on during the 90's, but the technology needed to catch up.

Since then, according to Taylor, he and his company have striven to design a system which "could compete straight on economics against fossil fuel in an international market." The buoy-pump device which they're now selling as part of that system is called the Power Buoy. It's a "smart buoy", says Taylor, which purports to avoid many of the previously mentioned obstacles faced by buoy-pump systems, via a few key design innovations:

  • The piston/pump workings are built into the buoy itself, which means better control and optimization of their workings, and less deep-water work for deployment and upkeep. Only the generator is deployed underwater with the Power Buoy system. The generator is driven by hydraulic fluid pumped down from an array of Power Buoys. It sends DC current to shore, where it's finally converted and put on the grid.
  • Innovative moorings - the Power Buoy has optimized moorings so that, when a storm surge rolls in, the buoy "lays down" near the bottom, avoiding the heaviest seas. The Power Buoy is deployed almost completely underwater, displaying only a small warning bell/light and air-hose above the surface. It can adjust it's buoyancy automatically, to be able to "run deep" in heavy storms.
  • Computerized control - the buoyancy and piston workings are controlled by a computerized controller which is built into each buoy. This allows for realtime monitoring and adjustments of the system, as well as functionality to predict the approaching "next" wave. This prediction of the oncoming wave helps the Power Buoy to approach true resonance with each wave, and harvest maximum power.
  • The Power Buoy also utilizes the piezoelectric streamers mentioned previously to harvest additional power. While it's unclear how much additional power these devices contribute, they do optimize the potential of the base design.

Testing the Power Buoy

With the backing of the US Navy, OPT tested it's system on the shores of New Jersey where the company is based. That test, which utilized a scaled-down prototype version of their current device, seems to have been a success. The device produced reliable power which powered an underwater Navy research sub. More importantly perhaps, the original test of the Power Buoy proved that it could withstand very heavy seas - in the fall of 1998 Hurricane Bonnie pounded their demo unit pretty hard, and it stood up well. According to Taylor,

"The ocean's a tough environment, people who have tried to use wave energy before have all failed. We hold the world record for a system that works in the ocean."
With the success of the demo unit behind them, during the middle of 2001, OPT announced that the Navy had decided to fund, to the tune of $4.5m, the testing of the Power Buoy system in a large scale deployment off of the coast of Hawaii. Ostensibly, this test was to produce 1 megawatt of power, although that number has since been reduced. In Hawaii, like lots of other places, there's a significant power crunch due to lack of new generating plants, but there's also significant resistance to another conventional plant, making the Power Buoy an attractive alternative.

As mentioned, the Office of Naval Research is funding the test, with the intent of eventually handing over the production and maintenance of the station to the local power company. Updates on this test, unfortunately, have not been forthcoming from OPT.

The announcements indicated that the first Power Buoy would be installed by September of last year, however. And since then, military reporters have talked up the experiment on their base websites, with the latest report coming in November of last year. The report seems to allude to positive early results, even noting that the Power Buoy can produce 100kw of power - but when I contacted OPT directly to ask about the results, I was sent a polite, but very uninformative reply. I also contacted the local Hawaiian reporter who covered the kickoff in mid-2001, but she hadn't looked in on the progress of the test since her report. I even dropped a line over to the Navy Research folks who were responsible for the articles on the base websites, but when they couldn't "find me in their reporter-database", they summarily ignored me. Ah well.

The Power Buoy is also being tested in Australia. The original announcement, in July 2001 states that the station built will generate 10 megawatts, although that estimate has been sized down somewhat, possibly due to delays approving deployment sites, but you'll soon see there's a bigger reason than that. In any case, a local report from June 2002 has a really nice picture of the full-sized production model Power Buoy, ready to ship out to it's new home on the Victoria coast near Portland. There's also an Australian oil/power company called Woodside which has become a significant investor in OPT, and has secured the rights to sell the Power Buoy in the region, through their alternative energy subsidiary.

Is this the next wave, then?

As previously mentioned, wave power has great potential. In some areas (map) of the world, the ocean wave contains as much as 100kw of potential energy per linear meter of wave-front. A look at the map also shows that it's generally more widely dispersed over the world, although it does require coastline, heh. Researching this article, I was impressed with the possibilities, and especially with the Power Buoy. Unfortunately, some discrepancies have forced me to conclude that, at least for the time being, this "breakthrough technology" may need a few more years before it has a chance of becoming competitive.

Note how, in the original article from Jan. 2003, which I tantalizingly linked-to above, the reporter (Linda A. Johnson) states that, "A total of six (Power Buoys) are to produce a combined 1 megawatt of power," for the Hawaiian test. That's a much smaller number of buoys than was reported originally, at the time the project was announced. Originally, the Hawaii deployment called for 20 Power Buoys, each producing 50kw of power. Unfortunately, I feel pretty certain that, the real error in Johnson's report was leaving off a "0". The fact is that to produce a megawatt of power will require at least 50 Power Buoys.

The problem, it seems, is that the estimates of the power production capabilities of the Power Buoy are being, um, slightly overestimated. Studying a recent Australian report on the Power Buoy deployment reveals the true capacity of the Power Buoy to be something in the neighborhood of 20 kilowatts, and not 50, and certainly not 167, as claimed by Johnson, even in the most recent article.

Since this article was published, the Australian government has taken down their original report which I linked to above, related to the actual (20kw) output of the Power Bouy. However, you can still find the document on the Internet Archive.

Now, that's not to say that OPT's intentions aren't good. The Australian report also notes that the company is "looking at developing" 100kw Power Buoys in the future - but, and in spite of Robert's claim that all of OPT's employees, "feel that they're doing something that may be important to the world," I'm left slightly non-plussed by their chances. Again though, their buoy is the clear winner for surviving bad weather, and some of the design innovations, at least those that haven't already been patented, will likely be copied, although others will likely be claimed as prior innovation by non-American interests.

In any case, wave power isn't mentioned at all in the Bush report, and I'd like to believe that it's got more potential than that, even in the US, where the coastline doesn't have the wave-power potential that's found in other parts of the world. The technology, otoh, at least for buoy-pump devices, still needs a bit of work.

Additional References

It is as yet rather difficult to find updates regarding progress made on wave power during 2002, but the summaries and reports for 2001 are interesting. A few of those are linked below.

  • World Energy Council Survey of wave power technology, as of late 2001. Includes a more complete look at the Pelamis, as well as an overview by country of the research. (Mentions OPT)
  • Technology Updates a review of Wind, Wave, Tidal and Solar power research from around the world.
  • Oceans of Electricity - a good review of the OWC technology, as of late 2001. Includes coverage and references to the deployed versions of the Oscillating Water Column technology.
  • Scientific Applications and Research, an organization which is also funded by the US Navy, has another buoy-pump design which is interesting because the design has been awarded patents on certain aspects of the technology. Unclear whether, or if OPT is utilizing any of this design functionality. What is clear, is that the US Navy has a strong interest in these devices.
  • University of Edinburgh - Wave Power Group - academic home of some of the pioneers of wave power technology.

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Best alternative energy source?
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o generated new interest
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o up to 16% of the world's needs
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o for decades
o 1000 patents
o diverse
o Oscillatin g Water Column
o Wells Turbine
o recent optimizations
o Mighty Whale
o The Flapper
o Pelamis
o Heaving buoy-Pump
o anchored to the ocean floor
o Ocean Power Technologies
o George Taylor
o Wave Power Research Division
o Office of Naval Research
o latest report
o covered the kickoff
o original announcement
o delays approving deployment sites
o local report
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o some areas (map)
o original article
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o Australian report
o Internet Archive
o World Energy Council Survey
o Technology Updates
o Oceans of Electricity
o Scientific Applications and Research
o buoy-pump design
o University of Edinburgh - Wave Power Group
o Also by imrdkl


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Catch a Wave: Profitable Alternative Energy? | 177 comments (149 topical, 28 editorial, 0 hidden)
Good point about survivability (4.00 / 2) (#3)
by Rogerborg on Wed Mar 05, 2003 at 07:18:25 AM EST

One of the first OWC prototypes deployed (or not deployed) in Scotland sunk en route to its site.  Its 25 year active life turned out to be a little optimistic.

The Islay project you reference is a good example of another way to do OWC, building out from the shore rather than towing in from the sea.  In a severe storm, you might lose the turbine, but hopefully not the whole structure.

Even so, there's an inherent risk in any wave power scheme that weather patterns will shift during the lifetime of the device.  I'm not clear on whether the heaving buoy design is designed to be moved, but that would seem to be a sensible feature in such a device.  Any thoughts?

"Exterminate all rational thought." - W.S. Burroughs

Avoiding heavy storms (none / 0) (#44)
by imrdkl on Wed Mar 05, 2003 at 03:09:05 PM EST

If I understand you correctly, you're question is about storm protection for the buoy. This is, or has been a bad problem for them, as I understand. Even the devices which have their workings (pump, piston, generator) underwater like the Danish version, could be adversely effected by waves which are too big.

To deal with this, most pump-buoy devices implement a lock in the piston which kicks in when the waves are too high for safe operation. As mentioned, the Power Buoy has a way around the problem by submerging itself deep and waiting out the storm surge. This seems to me to be a superior solution.

[ Parent ]

Physical relocation (none / 0) (#45)
by imrdkl on Wed Mar 05, 2003 at 03:15:13 PM EST

I haven't considered that. Presumably the Power Buoy would only need to be lifted up, towed, and reset with new moorings. Other buoy-pump devices would present a much more difficult case, I suppose.

[ Parent ]
This isn't neccesary (2.33 / 3) (#4)
by psychologist on Wed Mar 05, 2003 at 07:19:23 AM EST

We should be concentrating on getting energy from the really inexhaustible sources of energy. For example, if we build a device that taps into the negative energy created right here in the kuro5hin diary section, we will never need to sink another oil well again.

Right, that's it (5.00 / 4) (#9)
by Rogerborg on Wed Mar 05, 2003 at 08:07:49 AM EST

I'm invoking a derivative of Godwin's Law.  

"As a K5 discussion grows longer, the probability of an assertion that K5 is teh suck approaches one."

"Exterminate all rational thought." - W.S. Burroughs
[ Parent ]

Great Stuff (3.50 / 2) (#7)
by OldCoder on Wed Mar 05, 2003 at 07:53:18 AM EST

Unless this turns out to be another story like Cold Fusion, which also generated great enthusiasm when it was first announced. Crank it up.

Any info on Tidal Power? Every few years somebody proposes using the massive motion of the tides as a way to generate electricity, then it goes away. Google turns up lots of links for "tidal power", here's one that looks interesting, they seem to be worried about the fish. Some people are never happy.

--
By reading this signature, you have agreed.

Tidal power (5.00 / 1) (#11)
by pmc on Wed Mar 05, 2003 at 08:37:57 AM EST

Just say no.

Oh - you want more? Firstly they are very expensive in energy terms. It takes a lot of power to make and transport all that cement. Secondly they have a slightly longer phase than half a day (well 12hrs 24 minutes IIRC) so they get out of sync with when the power is required. Thirdly there are relatively few places in the world - Bay of Fundy, Severn Estuary, English Channel (again from memory) are the three biggies - that tidal power is worth while, because the tidal range is so large. And a large tidal range requires huge barrages (see point 1). Tides vary in size (springs to neaps) making syncing them to power requirements even more troublesome.

Things would be a lot more practical for tidal (and solar, and wind) if there was a good energy storage medium to iron out these phases, but short of fairly inefficient hydro pumping (40% or there abouts) there's nothing. And my 2d worth is that that is where we should be putting the money for research.

[ Parent ]

This is a long term problem (none / 0) (#17)
by xria on Wed Mar 05, 2003 at 10:00:28 AM EST

Clearly the passive nature of all alternative energy sources, which is one of the reasons they are so beneficial in theory, also has this side effect of not providing energy necessarily when it is wanted.

There are a few ways around this that I can see:

-Find a friendly and efficient way of 'storing' energy
-Find a new alternative energy source that can be ramped up as needed
-Always rely to some extent on conventional 'burn stuff' type approaches to cover the difference
-Have alternative energy in so much abundance that there is always more than needed, so that spare capacity can be disabled when not required.

[ Parent ]
you missed an option (none / 0) (#27)
by gauntlet on Wed Mar 05, 2003 at 11:53:26 AM EST

it's not popular, but it deserves mention:

reduce our energy needs, and use multiple alternative sources of energy in order to prevent total blackout.

Into Canadian Politics?
[ Parent ]

Energy Conservation (none / 0) (#35)
by xria on Wed Mar 05, 2003 at 12:40:49 PM EST

For me conservation is over all, its potentially far cheaper and easier that any way of creating energy is less problematic ways.

Unfortunately a lot of our culture is deliberately wasteful as it is more profitable - look at the history of VW after World War II as an example of how the free market creates a situation where it is better for manufacturers to make things that either wear out, or become unfashionable on an ongoing basis.

[ Parent ]
Energy conservation isn't cheap (none / 0) (#177)
by ZorbaTHut on Tue Mar 11, 2003 at 02:07:12 AM EST

I've heard that statement a lot, but unfortunately, I think it's flawed in economic terms. (Note: I am not an economics major, this is just remembering an economics class I took in college and my own feelings on the matter, and why I use big speakers and a computer that doubles as a room heater.)

See, the cost isn't just referring to the sheer dollar value. There's also how much people are inconvenienced by it. If you want to put everything in money terms, it's how much people would be willing to spend to *not* conserve power.

And it seems pretty obvious, once it's put in those terms, that people aren't really willing to spend all that much - or at least, that the benefit isn't nearly as much. Yes, my friends and I could probably chop out an enormous amount of power consumption. Most of my friends don't turn their computers off at night, some of them have multiple boxen, I personally have a dual-Athlon 9700 Pro behemoth with five hard drives and ten fans.

On the other hand, we pay less than $20/mo each for power. (We have gas heating in the house, so that's not included.) (Well, unless you count all the Athlon CPUs, but anyway.) $20/mo isn't all that much. In fact, if you came up to me and told me that power costs had gone up by a factor of five, I *still* wouldn't do anything - I can live with $100/mo electric bills without a problem, and the work I'd have to do to bring that bill down just plain wouldn't be worth it.

So there's the cost of energy conservation to me - several hundred dollars. This is why I don't bother conserving. It ain't worth it to me. I'm a fundamentally selfish person (most people are, if not all), and eliminating the minute amount of pollution that my power usage is creating (as well as reducing my power bills by $10/mo perhaps) just isn't worth the time.

So there it is. For me, it's not cheaper *or* easier. So I'll continue wasting power.

[ Parent ]

pole power (none / 0) (#60)
by phlux on Wed Mar 05, 2003 at 04:23:23 PM EST

what if you had a big pole secured to the floor of the ocean. At the top of the pole was a huge float that the pole ran through the center of.

The float would move up and down the pole with the waves and tide - the movement of the float would produce power (through whatever means - hydraulic pressure etc..)

The surface of the float would be covered in solar cells.

The top of the pole would have a windmill on it.

This device would be big/small enough to power a few houses on the coast... or maybe it could be big enough to power a small town on the coast for X amount of time.

It would be small enough and far off shore enough that it wasnt too much of an eyesore.


[ Parent ]

Nice (2.71 / 7) (#24)
by SanSeveroPrince on Wed Mar 05, 2003 at 11:40:26 AM EST

Good article. Nice to see someone talking about alternative energy sources that's not foaming at the mouth or trying to get me to cough up for Greenp***.

Still, the irony of the situation always makes me chuckle.

Alternative energy sources are currently simply not up to scratch for mass production of energy. Greenthumb people keep pointing out at isolated farms where this or that technique worked admirably, but they are always very specific geographic locations, with freak methereological conditions that allow for the use of water or wind powered gizmos that would fail to deliver anywhere else.

What delivers today, I'm afraid to say, is NUCLEAR. By the time alternatives are up to scratch, we'll all be enjoying crispy nuclear powered appliances. By the time alternative energy production is able to sustain our energy needs, nuclear power will already be everywhere, and we just won't need no stinking hippy wind generators or buoys.

And because I'm a mean person, a mean person with a grudge against all nature-loving hippies, it makes me smile. Sometimes it makes me cackle.

----

Life is a tragedy to those who feel, and a comedy to those who think


Nuclear power isn't ready (none / 0) (#65)
by dachshund on Wed Mar 05, 2003 at 04:59:26 PM EST

What delivers today, I'm afraid to say, is NUCLEAR. By the time alternatives are up to scratch, we'll all be enjoying crispy nuclear powered appliances.

Nuclear doesn't deliver today. It's much more expensive than wind on a per-kw/h basis, and astronomically more expensive than gas and coal. Furthermore, a concerted move to nuclear would require a totally different type of generation than we use today; there simply isn't enough fuel in the world to support a massive build-out of non-breeder reactors (currently only rolled out as experimental projects.)

So you're looking at a totally different design for nuclear plants, a new fuel reprocessing and transportation infrastructure that doesn't exist yet, and a public that just loves the idea of highly-processed fuels like Plutonium. I don't think these things are quite ready for delivery in the near future.

The energy supply of the future will almost certainly be some combination of cheap renewable power, and more expensive, difficult nuclear power. The goal will be to maximize the renewable power, but keep the nuclear power on grid to stabilize production during generation lulls (most renewable sources don't have a constant output.)

From what I understand, non-constant sources like wind (and possibly wave-power) can generate up to 25% or so of the nation's normal power needs. That's not including things like electrolyzing hydrogen from water for transportation, which could be done with additional, non-constant sources.

[ Parent ]

and that... (none / 0) (#71)
by heng on Wed Mar 05, 2003 at 06:08:44 PM EST

is even before you need to worry about the highly radioactive junk left over, what to do with it, and what to do with the decommissioned plants. All the current nuclear facilities were built, and still are being built, with the assumption that the technology for safe decommissioning will become available when the time comes.

Dounreay in Scotland is expected to take 50-60 years to decommission and cost UKP 4 billion. That's some cost.

[ Parent ]
Not to mention... (none / 0) (#77)
by Eccles on Wed Mar 05, 2003 at 07:56:28 PM EST

Nuke plants are a concern as a terrorism target. No one's worrying about terrorist attacks on wind farms...

[ Parent ]
Major producers are targets either way. (none / 0) (#101)
by subversion on Thu Mar 06, 2003 at 07:05:28 AM EST

Sure they are.  If you had a wind farm producing as much electricity as a nuke plant, it would be a major target for this simple reason:

The amount of terror caused by the sudden elimination of a regions electrical supply will dwarf that caused by a meltdown.

Now, if you're talking decentralized wind farms, that's a different story.  On the other hand, wind is generally a localizable source - for instance, it isn't going to produce energy very well where I live, because we don't have a ton of wind most of the year (not to mention the whole ice storm thing, which we seem to get a ton of).  The only way to make it efficient as a supply for us would be to place a huge farm somewhere where natural conditions produce an excess of wind, and then we're back to the large centralized production problem.

If you disagree, reply, don't moderate.
[ Parent ]

No way (none / 0) (#104)
by dachshund on Thu Mar 06, 2003 at 08:31:09 AM EST

The amount of terror caused by the sudden elimination of a regions electrical supply will dwarf that caused by a meltdown.

I highly doubt that. What you mean to say is that the number of casualties might be greater in an outage than in a meltdown (assuming ideal conditions for the meltdown, such as limited exposure to the population.)

However, for sheer terror purposes nothing beats a nearby meltdown to scare the shit out of people. As bad as it can be for the elderly or disabled, a power loss usually doesn't induce abject terror in a population.

[ Parent ]

Gotta disagree. (none / 0) (#106)
by subversion on Thu Mar 06, 2003 at 09:23:35 AM EST

A power loss that's going to go on for weeks, months, or longer (how long do you expect it would take to replace that kind of generating capacity, exactly?) will induce a helluva lot more terror in your average American than a meltdown.

NOTHING works.  Over a large area.  Expect rioting, looting, general disarray, as well as major economic disruptions.  Imagine if, for example, suddenly New York City didn't have power.  Who the hell cares about the meltdown way out on Long Island?  The simple fact would be that the disruption caused by something like that would extend, via indirect economic effects, far further than the more localized effects of the meltdown.

I did not, in fact, mean casualties.  I assume casualties to be higher in meltdown, for obvious reasons, but the terror and disruption induced by a long-term electrical malfunction of a populated area will be greater by far than that induced by a meltdown.

Note: a nuke attack would indeed induce greater terror, because you get both the meltdown and the blackout, but the order of magnitude is greater for blackout than meltdown.  To use scientific terminology, the terror produced by meltdown would be a negligible term in comparison.

Note:  if the electrical supply is supplying a sparsely populated area, of course the wide-scale disruption would be less, but generally sparse areas don't require hundreds of megawatts of power.

If you disagree, reply, don't moderate.
[ Parent ]

How does this happen? (none / 0) (#114)
by dachshund on Thu Mar 06, 2003 at 12:52:28 PM EST

A power loss that's going to go on for weeks, months, or longer

What in the hell kind of attack is going to destroy an entire wind farm for that period of time? If anything, wind farms are less vulnerable than just about any other power source we've invented, simply because they have a greater footprint and a lot more redundancy. To actually put one out of business, you'd probably need a nuclear weapon (at which point, shutting down a wind farm is probably not going to be your number-one goal.)

Of course, you could go after the distribution infrastructure, but I'm having a hard time picturing an attack so widespread and diabolical that it would result in a multi-week (or month) outage. If we're vulnerable to that sort of attack, the method of generation is pretty much irrelevant.

[ Parent ]

An example. (none / 0) (#119)
by subversion on Thu Mar 06, 2003 at 01:49:13 PM EST

Given a large wind farm, you have to have some means of aggregation of the generated power before its distributed to the grid.

Destroy the aggregation machinery (and remember, we're talking equipment that handles hundreds of megawatts of power - not exactly drop-in hardware, here) and you've effectively taken out the power capacity.

I can easily imagine multi-week outages from a circumstance like that, even if the actual generation machinery (wind turbines) is unaffected, the aggregation, balancing, and distribution hardware is smaller, more centralized, and easier to destroy.

If you disagree, reply, don't moderate.
[ Parent ]

Hmm (none / 0) (#141)
by dachshund on Thu Mar 06, 2003 at 10:54:08 PM EST

Destroy the aggregation machinery (and remember, we're talking equipment that handles hundreds of megawatts of power - not exactly drop-in hardware, here) and you've effectively taken out the power capacity.

Same can be said of any other type of power plant. Or the distribution infrastructure, for that matter. The difference is that in wind systems only the aggregation is going to be destroyed by such an attack, whereas in a traditional plant you could lose the entire thing (or see it suffer massive damage that makes quick recovery impossible.)

In any case, if we get to the point you're concerned about-- where terrorists are actively targeting our power generation systems-- I hope we'll have redundant hardware in place (or nearby) so we can prevent such disasters.

[ Parent ]

Right, but my point (none / 0) (#144)
by subversion on Fri Mar 07, 2003 at 05:35:25 AM EST

Was that the electrical generation being knocked out would be more terrifying/disrupting than a meltdown, because it would probably directly affect more people.

Aggregation hardware is really not going to be drop-in replaceable for a long time, if ever.  Once again, you're talking about something that needs to handle hundreds of megawatts of power.  It'd be like trying to design a drop in replacement for Launch Complex 39.

Now that we've established that anything that isn't decentralized (and centralized populations - i.e. major cities - require centralized power) is vulnerable to disruption, we can go back to my point - a sustained (really, anything longer than about a week over a large area) disruption will do more to terrorize people than the meltdown would.

If you disagree, reply, don't moderate.
[ Parent ]

Can't tell til it happens (none / 0) (#146)
by dachshund on Fri Mar 07, 2003 at 08:10:07 AM EST

I still don't agree with you because meltdowns are just plain scary. People rarely run for the highways when the power goes out, but they will if they learn that there's a cloud of radioactive fallout heading for the city. That can cause enormous amount of mayhem before anyone even sees a particle of fallout. (Now imagine the power is out and fallout is headed toward the city. Think of the traffic accidents that will occur.)

Furthermore there are generally other reserve source of power that can be brought online in an emergency; even if power consumption has to be strictly rationed, some lights ought to stay on.

I think we're going to have to wait until it happens to see how people deal with the outcome.

[ Parent ]

Only agree on one point. (none / 0) (#149)
by subversion on Fri Mar 07, 2003 at 09:57:40 AM EST

People don't run for the highways when the power goes out, but you tell me that the power being out for a week in metro NYC, or metro LA, or any other major metropolitan area, wouldn't be far more frightening than a meltdown 150 miles away.

I agree with you that we'd have to wait and see, but claiming that major generating capacity wouldn't be a target no matter the type is simply incorrect.  Terror would be generated either way, and the likelihood is that a wind plant would be less guarded and easier to sabotage.

If you disagree, reply, don't moderate.
[ Parent ]

From personal experience (none / 0) (#164)
by dachshund on Sat Mar 08, 2003 at 06:15:13 PM EST

but you tell me that the power being out for a week in metro NYC, or metro LA, or any other major metropolitan area, wouldn't be far more frightening than a meltdown 150 miles away.

Having sat tight in NYC through Sept. 11th and the days of smoke and weirdness afterwards, I can tell you that people are a lot tougher than you think. What you'll see during a prolonged outage is a lot of irritation and some panic. But I don't think it'd be anywhere near as fast and scary as, say, a Smallpox outbreak or a dirty-bomb detonation.

The more time the authorities have to react and bring in emergency services & national guard, the less mayhem you're going to see.

[ Parent ]

It's already vulnerable (none / 0) (#168)
by TheOnlyCoolTim on Sat Mar 08, 2003 at 10:40:33 PM EST

If power outages were such a tempting goal for terrorists, all they would have to do is cut down some of the high-voltage transmissions lines. 20 terrorists could probably have New York getting only a trickle of power pretty quickly, and they probably wouldn't get caught right away either.

They are entirely unguarded - I've stood directly under some out in the middle of some woods (if the terrorists wanted to go for a two-fer or cause an explosion, this was actually a crossroads where an underground gas pipeline passed beneath the wires.) and you see them all the time within a hundred feet of roads and sometimes a chain link fence in between.

So I don't think power outages are such a huge temptation for the terrorists.

I remember hearing the TV news one time report that these wires were unguarded like it was some shocking weakness, when in reality trying to guard these wires is impossible.

Tim
"We are trapped in the belly of this horrible machine, and the machine is bleeding to death."
[ Parent ]

Hrm. (none / 0) (#116)
by Eccles on Thu Mar 06, 2003 at 01:41:43 PM EST

Wind farm power plants are never compact. If they're shared with conventional farming, they may be spread over hundreds of square miles, and simply aren't a target for terrorists. Conceivably an offshore wind farm could be attacked somewhat more easily (explosives attached to supports by boat or submarine), but it's not exactly an obvious target, a typical offshore farm having hundreds or even thousands of fans spread over a large area. Nuke plants are much more centralized, making them more of target a terrorist who crashes a 747 into them. The cooling towers may be strong enough to resist such an attack, but that doesn't mean a terrorist wouldn't try; or they might target the control buildings if they just want to disable the plant -- but that's not a typical terrorist objective.

One possibility for wind farms might be to have oil derrick-like structures that travel/are towed to the windier, non-frozen areas as needed, although this may not be cost-effective or energy-efficient.

The windiest regions in the U.S., by the way, are mostly in Montana last I checked. That's a pretty sizeable (and largely empty) state.

[ Parent ]
You're not thinking like I am. Which happens. (none / 0) (#120)
by subversion on Thu Mar 06, 2003 at 01:51:05 PM EST

If you want to generate hundreds of megawatts and power a city via wind, you'll have a more concentrated wind farm, and furthermore, you'll have aggregation/distribution hardware interfacing to the grid.  This will be your vulnerable point.

Decentralized wind farms can't power metropolises.  They're not what we're talking about.

If you disagree, reply, don't moderate.
[ Parent ]

Still irrelevant (none / 0) (#154)
by Eccles on Fri Mar 07, 2003 at 01:49:11 PM EST

Can you name a terrorist threat that targeted a power source, merely for the impact of loss of power on people?  Nuke plants are a target because of people's fear of nuclear exposure, not the loss of the plant.  Dams are targeted because all that water suddenly moving downstream can kill many.

"Decentralized wind farms can't power metropolises. "

Why not?  I don't have the foggiest idea what plant is providing my electric power; it's certainly not next door.  While long-distance transmission of electricity is lossy, it's still possible and widely done.

[ Parent ]

Question of Waste (none / 0) (#79)
by Epssus on Wed Mar 05, 2003 at 08:38:48 PM EST

You fail to take into consideration the waste produced by other sources. Yes, nuclear waste is tough to deal with, and hard to store But when you're dealing with something like a fuel/coal burning plant, you're just spewing carbon and nitrogen compounds out into the air, that by and large, are just as surely hazardous to your health as a bit of radioactive waste. The plain fact is, that while so much ruckus is raised about the cost and difficulty of dealing with nuclear waste, you forget the fact that we barely even bother with exhaust waste, we simply do a little to reduce them, and by and large ignore the rest. Think of how hard it would actually be to deal with all the waste gases produced by fuel burning plants, if we actually did something about them, and storing nuclear waste that amounts to mere fractions by quantity all of a sudden doesn't seem quite so bad. Its all a question of scale - one nuclear plant vs several dozen coal plants (still our primary power source).

[ Parent ]
yes (none / 0) (#96)
by heng on Thu Mar 06, 2003 at 03:44:27 AM EST

That is why we should be concentrating on renewables ;)

[ Parent ]
Yeah (3.50 / 4) (#25)
by trhurler on Wed Mar 05, 2003 at 11:48:44 AM EST

This is kind of nice; I've seen it before. There's no real reason it can't be done, but keep in mind that the only thing you can reasonably do is produce electricity with it. That's fine for replacing coal plants, but it doesn't do anything about oil dependency unless and until electric cars become competitive. And note: I do mean "competitive." Why? Because outlawing the only useful means of transportation in the US that covers more than a tiny fraction of a percentage point of the land mass is not going to be politically viable; anyone who voted for that would be bounced out of his office the very next day by a mob eager to tear him limb from limb. Also, remember that a huge fraction of US bought oil goes to commercial vehicles, which cannot easily be made to operate using electric motors with today's technology. Sure, the motors can spin the wheels, but where do you store that kind of power? The batteries required would be impractical, to say the least.

So, as long as nobody goes around promoting this as a panacea, it is cool. It really could displace coal plants and perhaps just as importantly reduce the desire for hydroelectric dam power.

Still, the ultimate in future power remains hydrogen fusion, baby. Mmm... yeah.

--
'God dammit, your posts make me hard.' --LilDebbie

Synthetic fuels (none / 0) (#30)
by Edgy Loner on Wed Mar 05, 2003 at 12:14:00 PM EST

You're not completely correct. Abundant, cheap electricity could be used as an energy source to create synthetic fuels for vehicles. It's not super efficient, but with enough electricity, that's not a problem.

This is not my beautiful house.
This is not my beautiful knife.
[ Parent ]
Sort of (none / 0) (#32)
by trhurler on Wed Mar 05, 2003 at 12:23:34 PM EST

But unless there's work I haven't heard of(unlikely, really, since I follow fuel related issues, but possible,) synthetic fuels aren't exactly mass market ready:) The real issue here, though, is that even synthetic fuels are still going to be hydrocarbon chains that you oxidize to get energy, and that will still produce emissions, and this will still be a problem for the enviro-weenie set who think the sky is falling.

Me, I'm all for burning the enviro-weenie set as extra fuel for the coal plants, but to each his own, I guess...

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
Welcome to ... (none / 0) (#39)
by awethu on Wed Mar 05, 2003 at 01:38:27 PM EST

the wonderful world of SASOL, owner of the world's only commercial coal-based synfuels manufacturing facility, which produces 150 000 bbl/day. This process is economically viable as long as oil prices remain above $18/bbl.

Of course GTL synfeul is significantly more efficient (and a whole lot cheaper if flared gas is used) and major commercial projects are underway around the world, including Nigeria, Australia and Qatar to name a few.

[ Parent ]
Well... (none / 0) (#41)
by trhurler on Wed Mar 05, 2003 at 01:51:38 PM EST

If it is coal based, then it isn't REALLY all that synthetic, is it now? :) It isn't like we can just make more coal, after all, unless we develop a synthetic coal industry!

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
No net carbon gain (3.00 / 1) (#42)
by Edgy Loner on Wed Mar 05, 2003 at 02:08:54 PM EST

Depending on the details of the process of course. Assuming the the synfuel was carbon based, burning it would would of course produce CO2. Ideally ther wouldn't be much else other than water vapor in the exhaust stream. The production process would need to get it's carbon from somewhere. Presumably it could get it either directly from the atmosphere, or preconcentrated by some biological process. The end result is a big carbon cycle with the same carbon being cycled between fuel stock and the atmosphere, instead of the current system where old carbon from fossil fuels gets a one way trip into the atmosphere.

Now maybe synfuels aren't practical today, of course we don't have the abundant, cheap electricity today either. I was just pointing out a possibility.

This is not my beautiful house.
This is not my beautiful knife.
[ Parent ]

in principle maybe (none / 0) (#37)
by radish on Wed Mar 05, 2003 at 01:13:17 PM EST

but in practice, "enough" electricity is really a hell of a lot, unless you're talking about 2H2O -> 2H2 + O2.

hydrogen is dead easy to make with electricity so it's a possibility, but it's very cumbersome and dangerous to store and transport in any quantity.  methane and alcohols are a lot cheaper to make with bacteria and yeast (specially ethanol - yum!) and probably will be until we can pull carbon out of CO2 as efficiently as plants do.  and last I heard about it, the more complex hydrocarbons that we actually use now (propane, octanes etc) are varying degrees of horribly inefficient to synthesize.  and not for lack of trying.

[ Parent ]

Commercial Vehicles. (none / 0) (#49)
by ambrosen on Wed Mar 05, 2003 at 03:34:58 PM EST

Can run on biodiesel. ASDA (UK arm of WalMart) run their trucks on used frier fat from their food production processes. It's also energy efficient to grow oils directly for use as fuel.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
partly true (none / 0) (#53)
by trhurler on Wed Mar 05, 2003 at 04:00:16 PM EST

Nobody runs their trucks purely on used frier fat, because there isn't enough of it. Even if every one of your trucks was 100% full of fried foods, given that you really only probably change the oil in your friers maybe twice a day, you won't have enough. I'm sure ASDA does the same thing most other people do - mix biodiesel with regular diesel. As for being energy efficient to grow oils for fuel, the problem isn't the efficiency of the fuel. The problem is the economics of growing it - you need a lot of biomass to produce a relatively small amount of fuel, and the farmers have to make a living somehow.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
Fair point. (none / 0) (#59)
by ambrosen on Wed Mar 05, 2003 at 04:22:39 PM EST

I shouldn't quote vaguely remembered press releases as verbatim, should I. They produce 50 million litres of used oil a year, which is certainly not to be sniffed at. After all, each truck only takes say 5% of its load as fuel (figure plucked from the air), so it's not as out of the question. I'd certainly say that if every truck was full of fried food, there'd be enough waste oil to power it.

It is efficient to produce, and efficient to use at current food oil prices (35p/litre in the UK). From http://www.biodiesel.org/pdf_files/LifeCycle_Summary.PDF

The total energy efficiency ratio (ie. total fuel energy/total energy used in production, manufacture, transportation, and distribution) for diesel fuel and biodiesel are 83.28% for diesel vs 80.55% for biodiesel. The report notes: "Biodiesel and petroleum diesel have very similar energy efficiencies."
I'd have thought it would be a solution to low prices at farm gates if it were widely adopted. I'm sure I've seen more useful estimates of how much land it would take to grow enough fuel to take up a significant amount of the diesel market, but I can't find them now. Sorry.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
Here's my estimate (none / 0) (#76)
by Eccles on Wed Mar 05, 2003 at 07:54:46 PM EST

In a Slashdot message a little while ago, I estimated whether us all going vegetarian could release enough land to produce biomass to power our cars: "Gasoline has approximately 31,000 calories/gallon, according to howstuffworks.com. Let's say people eat approximately 2500 calories per day. Now for fuzzier numbers: how many gallons/person/day. Warranties estimate 12,000 miles/year, say one (fully-used) car for every two people, each driven on average 32 miles/day, if 25 mpg we get 1.3 gallons/per car. Multiplied by calories yields ~40,000 calories/car/day. .5 cars/person nets 20,000 calories/person consumed by cars. If animal sources net us about half our daily calories, and meat production is 10% efficient, then we normally use 12,500 + 1250 vegetable calories/day. Since we'll still need that base 2500, that gives us ~11,250 more veg calories/person/day production capacity if we switched to entirely vegetarian diet. So it's ballpark, but still on the low side."

[ Parent ]
Another advantage. (none / 0) (#123)
by ambrosen on Thu Mar 06, 2003 at 04:02:53 PM EST

Of course, one of the advantages of using oils from biological sources is that once you've extracted the oil, there's high protein residue left over. That's a pretty good way to feed animals, too.

(BTW it's "Calories" (=kilocalories), not "calories")

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
Fusion, heh (none / 0) (#50)
by imrdkl on Wed Mar 05, 2003 at 03:39:22 PM EST

I'm also impressed by these, even though I had to nick them a bit for the hype. They're clearly the leader in this type of device, and while they won't solve the world's problems any time soon, they're definitely cool, and already ahead of their time. I'm not sure what went wrong with the original estimates, but I hope to find out, and I hope they can be reworked a bit to meet the original goal - because the numbers do work, when each one generates 50kw (or more) as promised.

[ Parent ]
Hydrogen? (none / 0) (#62)
by dachshund on Wed Mar 05, 2003 at 04:48:48 PM EST

his is kind of nice; I've seen it before. There's no real reason it can't be done, but keep in mind that the only thing you can reasonably do is produce electricity with it. That's fine for replacing coal plants, but it doesn't do anything about oil dependency unless and until electric cars become competitive.

Isn't that the whole point of the hydrogen-powered car initiative? I realize it isn't going to happen tomorrow, but I also doubt practical wave power is going to be in place for a number of years, so let's not focus too much on the short-term.

It's interesting... one day I read a bunch of Slashdot posts complaining that hydrogen cars won't solve our emissions problems because we lack sufficient renewable power to generate hydrogen cleanly. Then a few days later I'm reading a k5 post implying that our real problem cuts the other way, and unlimited renewable energy won't do us much good.

[ Parent ]

Well... (none / 0) (#64)
by trhurler on Wed Mar 05, 2003 at 04:58:39 PM EST

Wave power isn't going to be cheap enough even by the wildest estimates to make hydrogen production a cost effective alternative to current fossil fuels. Renewable and cheap are not the same thing.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
Innovation (none / 0) (#67)
by dachshund on Wed Mar 05, 2003 at 05:08:19 PM EST

Wave power isn't going to be cheap enough even by the wildest estimates to make hydrogen production a cost effective alternative to current fossil fuels. Renewable and cheap are not the same thing

And 640k of RAM...

That's the thing about renewable power sources. Fuel is never an issue so all that matters is the cost of building the sources, installing and maintaining them. That's the place where you can't really make any predictions, because innovation will always surprise you.

Look at estimates of wind-power costs dating from the 1970s and compare them to today, you'll see that they're totally out of line with what modern turbines can do. Newer materials, advances in design, bigger turbines, etc.

[ Parent ]

Re: poll (2.33 / 3) (#29)
by guyjin on Wed Mar 05, 2003 at 12:02:31 PM EST

I chose 'Wind' because I presumed you meant harnessing and igniting flatulence. It just now occured to me that you might mean something else ;-)
-- 散弾銃でおうがいして ください
Write-in vote: nuclear (2.50 / 4) (#36)
by leviramsey on Wed Mar 05, 2003 at 12:43:03 PM EST

Or nucular if you happen to live at 1600 Pennsylvania Ave.



Environmentalists and wave power (3.16 / 12) (#38)
by epepke on Wed Mar 05, 2003 at 01:17:49 PM EST

It's rather distressing to see self-proclaimed envirnomentalists such as David J. Bellamy going for this kind of thing.

I live in Florida, and we're losing our public beaches at an alarming rate due to relatively minor sea walls erected to protect the beaches of housing developments. Now we're talking about some sort of infernal machine to suck megawatts of power out of the surf?

Quite frankly, I'd rather see offshore drilling for natural gas.


The truth may be out there, but lies are inside your head.--Terry Pratchett


RE: Environmentalists and wave power (none / 0) (#57)
by Dougthebug on Wed Mar 05, 2003 at 04:14:09 PM EST

You'd rather see an oil rig than a few small buoys?  I'm not sure if you fully understand what is being proposed here.  The focus of this article is on arrays of heaving buoys which are mostly underwater, 1km offshore.  I see almost no way that this would effect public beaches.  Environmentaly speaking, its a hell of alot better than anything we have now.

[ Parent ]
Spot the difference (none / 0) (#61)
by epepke on Wed Mar 05, 2003 at 04:29:11 PM EST

You'd rather see an oil rig than a few small buoys?

Natural gas != oil. Natural gas is what you're more likely to find off the Florida coast.

The focus of this article is on arrays of heaving buoys which are mostly underwater, 1km offshore. I see almost no way that this would effect public beaches.

Energy is energy. Either you pull enough out of the environment in order to be useful, in which case there is an environmental effect, or you don't. Neither you nor I know what would affect beaches, once they are constructed. Are you really going to power Tampa with "a few small buoys?" Or is it rather going to be that the few small buoys are a pilot project, and if they turn out OK as toys, that a whole bunch more get constructed and we find out the environmental impact five years down the road? And by that time, Tampa is so dependent upon it that nothing can be done politically about it?

Environmentaly speaking, its a hell of alot better than anything we have now.

Maybe, maybe not. Everything that hasn't been tried at first appears to have no dangerous effects. I wouldn't mind seeing some experiments along the line, but I am amazed how environmentalists automatically assume that it would all be just peachy keen.


The truth may be out there, but lies are inside your head.--Terry Pratchett


[ Parent ]
Valid point, but (none / 0) (#63)
by imrdkl on Wed Mar 05, 2003 at 04:50:53 PM EST

The scientific writings that I read on this say that, "The best wave generator is also the best wave-canceller", or something to that effect. Deployed in a long enough row, these would certainly affect the eventual strength of the wave that arrives on shore.

However, with proper staggering, I believe the adverse effects initiated by a sea wall will be avoided.

[ Parent ]

Maybe, maybe not (none / 0) (#66)
by epepke on Wed Mar 05, 2003 at 05:07:06 PM EST

I'm not entirely an unwashed idiot in the matter. For one thing, I took a shower yesterday. For another, I worked with H.M. Cekirge and J. Sollohub to model and visualize the currents around Florida using a fairly sophisticated model that included temperature at various depths. I think that we were one of the first groups to find out that a significant amount of oil in an oil spill gets down to the continental shelf and messes up reefs there. We were also the only group correctly to predict the direction of an oil spill that happened near Tampa Bay close to a decade ago. I also remember that the EPA and the State of Florida just couldn't be bothered with it; as long as they could cover their asses with their PC surface models, it was good enough for them.

I don't know that energy from waves or tides would be a bad idea. My approach to it would be scientific: test it and see what happens, preferably where it isn't going to ruin a lot if it all goes wahoonie-shaped. What distresses me is seeing environmentalists jump on the bandwagon because it sounds good. I occasionally see walking-around type environmentally-aware people talking about how great hydroelectric power is, totally ignoring the fact that there are vast environmental consequences. I hope that people higher up aren't that stupid. But there's still this science fiction cultural mame of "wouldn't it be great if" that poses some danger. Since this is as yet untried, I'd like to see some caution.


The truth may be out there, but lies are inside your head.--Terry Pratchett


[ Parent ]
Fair enough (none / 0) (#68)
by imrdkl on Wed Mar 05, 2003 at 05:16:10 PM EST

You sound like someone who's concerned, and I respect that. If I may point out though, Florida is teh suck for potential wave power. (See the map linked above) The potential kw/sq meter in that area of the US are very low, which likely excludes it, generally speaking, from any real development of wave power at all.

Notwithstanding, the environmental impact of reduced wave strength for any potential deployment should be considered, especially if primo beaches are concerned.

[ Parent ]

Focusing Surf With Diffraction (4.00 / 3) (#40)
by Baldrson on Wed Mar 05, 2003 at 01:46:24 PM EST

I don't know the theory of operation but pillars to focus surf via diffraction was apparently put to use some time ago in Norway. The system I heard described was basically dependent on the existence of a fjord where a tunnel was bored up through the rock, from the entry point of the focused surf, to an artificial lake at the top of the fjord from which the water would then descend through a hydroelectric generator. Anyone have references?

-------- Empty the Cities --------


Yup (4.00 / 1) (#43)
by imrdkl on Wed Mar 05, 2003 at 02:22:46 PM EST

I believe you're talking about the Tapered Channel device (TAPCHAN). It's mentioned in the WEC report, linked in the references.

[ Parent ]
I think, for the sake of your pole, (3.50 / 2) (#48)
by Fon2d2 on Wed Mar 05, 2003 at 03:34:43 PM EST

you should explain the differences between tidal and wave power.

Would that be for..... (none / 0) (#54)
by Glowbit on Wed Mar 05, 2003 at 04:00:45 PM EST

the South Pole or the North Pole?

[ Parent ]
Tidal power (4.00 / 1) (#56)
by imrdkl on Wed Mar 05, 2003 at 04:10:54 PM EST

Tidal power is covered in the "additional references", but as I understand, it's harvested by the flow of water in and out of a river/fjord etc, due to the tidal fluctuation. The tidal generator is typically a turbine which is submerged deep in the river/fjord and spins as the tidal waters flow through it.

Waves on the surface do not affect these devices.

[ Parent ]

Tidal Wave Power (none / 0) (#92)
by KWillets on Wed Mar 05, 2003 at 11:11:43 PM EST

The main advantage of this technique is that it avoids expensive underwater construction. Power consumers simply generate power from the bobbing up and down motion of their houses.

[ Parent ]
Similar situation with wind (4.33 / 3) (#58)
by X3nocide on Wed Mar 05, 2003 at 04:22:05 PM EST

Theres been a lot of commotion about wind power in Kansas. I guess the combination of flat land and central land mass causes a lot of wind. So they want to build a few wind farms out in the Flint Hills, right outside of KSU.

I think its a great idea that will reduce emissions and bring money into the state.  The ecologists are concerned about birds. Apparenly birds are unfamiliar with large structures that catch wind.  Nevermind that house cats kill more than these turbines.  Additionally, the midwestern prairie chicken has lost most of its habitat, save the acres surrounding the Konza Prairie preservation.  There is concern that parallels the alaskan pipeline, that the huge infrastructure will disrupt the natural process. They suggest moving the wind farms further west in consideration of these poor birds.

I've got news for these people. First off, the Alskan pipeline has not adversely affected migrating elk population.  Some studies have even demonstrated that the elk migrate closer to the pipeline now, reasoning that the heat or some such attracts them.   The natural process is not something static that must be preserved, or even something that we can easily manipulate into being preserved.  Moving the wind farms further away from population centers means that the electricity must travel further, decreasing efficiency.  Which then requires more turbines to sustain society's growing energy demand.

I'm definately on board with alternative power. I think we all need to be.  Wind power's big advantage is that it can be deployed near by population centers and doesn't need to be transmitted across kilometers of ocean.  And with the falling price of food as farms become more efficient, alternative and economically feasible uses for land are a definite boon.

pwnguin.net

Minor nit pick: birds and house cats (none / 0) (#85)
by Repton on Wed Mar 05, 2003 at 10:11:51 PM EST

You said: Apparenly birds are unfamiliar with large structures that catch wind. Nevermind that house cats kill more than these turbines.

I dislike arguments like this.. You seem to be basically saying that house cats kill lots of birds, so if a few more birds die because of wind turbines, it doesn't matter. But the basic fact is that the number of birds dying will increase, which is (presumably) a Bad Thing.

I see similar arguments in, eg, drug debates: "Alcohol is legal and alcohol is worse than [drug], therefore [drug] should be legal." Still not a good argument, unless you are proposing that alcohol be outlawed at the same time as [drug] being legalised...

(please note: I'm not expressing an opinion on the drug wars, nor am I trying to start a debate.. I'm just giving an example of what I think is a bad argument)


--
Repton.
They say that only an experienced wizard can do the tengu shuffle..
[ Parent ]

Statistically insignificant perhaps (none / 0) (#111)
by X3nocide on Thu Mar 06, 2003 at 11:53:03 AM EST

Im inclined to believe that trees themselves represent a larger danger to birds. They're both large verticle structures with a trunk, but the tree has pointy sticks.

pwnguin.net
[ Parent ]
Wind is good (none / 0) (#98)
by imrdkl on Thu Mar 06, 2003 at 05:15:48 AM EST

But I should point out that, regarding wave power, transmission from the generator to the shore is optimized with DC current, and rarely extends much beyond the shoreline (to the converter). Also, to maximize potential, wind farms are typically deployed along the farthest edge of coastline. This requires long transmission lines to get the power to some city that needs it. That's not to say that there aren't good locations for wind power inland, but the best ones are on the coast.

[ Parent ]
Slightly OT: Results of the Poll (4.00 / 3) (#69)
by dachshund on Wed Mar 05, 2003 at 05:32:58 PM EST

Small sample sizes, I realize, but still I'm surprised to see so many people choosing solar power (and even geothermal) as the "best" alternative energy source, when wind power (and perhaps hydroelectric) are currently the most widely-deployed and practical alternative energy technologies around.

Wind is certainly growing at a much faster rate than any of the other technologies on the list, and it's being pushed as an actual deployable technology by for-profit companies-- whereas solar is currently languishing in the experimental stages.

I only comment because wind always seems to get far less publicity than solar, despite its major head-start. I understand the focus on solar power as the "poster child" of alternative energy whenever I'm reading some "alternative energy is years away" tirade (wind is generally ignored or totally misrepresented by those articles.) I'm just surprised to see this impression extends beyond that realm... Is solar just considered "cooler" than wind, despite the fact that we can't make it work yet?

The thing about solar (4.66 / 3) (#72)
by heng on Wed Mar 05, 2003 at 06:27:29 PM EST

Is that it is beautifully elegant. You produce this panel, and that's it. Save for keeping it relatively clean (which surface treatments can handle), it's virtually zero maintenance. This means that anyone can install and run a solar plant.

As an extension to this, every single roof in the world is a potential site for solar panels, that's a lot of space that is currently doing very little. There are many companies (such as solar century) around offering photovoltaic tiles that essentially replace slates - keeping the weather out as well as generating power. This is a very neat solution, and is starting to be financially competitive.

[ Parent ]
in theory (none / 0) (#115)
by dachshund on Thu Mar 06, 2003 at 01:14:44 PM EST

and is starting to be financially competitive.

My point is that wind power is already financially competitive than solar, and is ready for large-scale production.

Obviously solar sounds great, but we're years away from a practical solution, whereas economical wind power can be rolled out now (actually, it's already being rolled out.)

[ Parent ]

in tandem. (none / 0) (#118)
by ambrosen on Thu Mar 06, 2003 at 01:44:04 PM EST

No reason why developing wind power stops anyone developing solar power. After all, they're fairly complementary in the times they produce power.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
Ugly stepsister phenomenon (none / 0) (#140)
by dachshund on Thu Mar 06, 2003 at 10:45:00 PM EST

No reason why developing wind power stops anyone developing solar power. After all, they're fairly complementary in the times they produce power.

There's nothing I would love to see more than practical solar power. And of course it's not a zero-sum game. I just think it's a shame that wind-- which we should use now-- is relegated to the ugly-stepsister position. When people think of alternative energy, the first thing they tend to think of is solar. Then someone tells them that solar ain't quite there yet, and it tends to tar all alternative power.

I can't tell you how many articles I've read talking about our future energy generation plans that spent paragraphs knocking solar panels and then just forgot about wind. This one from the generally thoughtful Gregg Easterbrook manages to hit solar and even the totally blue-sky notion of fusion power while completely ignoring wind. Oops.

[ Parent ]

Not in Denmark. (none / 0) (#151)
by ambrosen on Fri Mar 07, 2003 at 11:00:31 AM EST

I forget how much of Denmark's electricity is wind generated, but it's already well over 20%, so in a way, wind may be considered a fairly mature technology. As for the bird impact, the (UK) Royal Society for the Protection of Birds is not too bothered. To quote the most relevent thing I could find, with reference to a planned new wind farm (at an old opencast mine)
The proposal does not represent any significant threat to the bird life of the area but does represent an exciting opportunity to deliver real biodiversity benefits through habitat management and creation.
I do remember them saying somewhere that the problems weren't great, but I couldn't find that.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
What is "alternative"? (none / 0) (#88)
by Repton on Wed Mar 05, 2003 at 10:21:49 PM EST

Is hydropower "alternative"?

Here in NZ, it accounts for 60% of the total electricy supply...

As to your question... Maybe solar power looks more "spacey" (because it is used on satelites &c), or maybe it just looks cooler (techno-looking panels, vs windmills, which have been around for EVER).


--
Repton.
They say that only an experienced wizard can do the tengu shuffle..
[ Parent ]

Solar makes sense (none / 0) (#97)
by gusCubed on Thu Mar 06, 2003 at 05:15:14 AM EST

From the 'energy chain' point of view, Solar power makes a lot of sense... although I can see how I'm going to argue myself out of that statement shortly.

There are three primary energy supplies available to us on earth:

  1. The sun
    • Solar power is energy derived directly from the sun
    • Wind power is energy derived indirectly from the sun - radiation from the sun heats the earth, causes convection currents in the air that ultimately result in wind
    • Fossil fuel is Solar energy stored by plants(coal)/plankton and the little sea critters that ate the plankton(oil) over millenia that we are now burning much faster than they were laid down
    • hydroelectric - the sun drives the water cycle - gives water gravitational potential (from the sea to the clouds)- which is lost as the water returns to the sea (rain -> rivers, via dams etc.)
  2. Decay of radionucleides
    • Conventional nuclear power stations rely on the decay of radionucelides -> accelerated fission of radionucleides -> heat -> electricity
    • Geothermal energy is derived from the heat caused by the decay of radionucleides in the earths core, and quite a lot of the gravitational potential lost when the earth formed from clouds of dust, gas and lint, as well as the energy imparted from ancient asteroid/comet impacts when the earth was forming
  3. Gravitational/tidal forces
    • Wave power is derived from the wind (from the sun) and the tidal forces generated by the moon's pull on the earths oceans (which incidentally means that the moon is receding from us at about a centimeter a year - conservation of energy strikes again)
    • Tidal power is derived directly from the tides -> the moons tidal effect (see above)

So anyway, of the solar generated renewables only 'Solar' is derived directly from the sun (albeit inefficiently - 15% I think is the best solar cell efficiency achieved commercially). All the others are derived indirectly - therefore some of the sun's initial energy 'input' is lost through other means - turbulence, heat ... ultimately heat. So they are bound to be less efficient - they are further down the energy chain if you like.

However as I wrote this I wondered whether wind/hydroelectric/wave power would be less wasteful of resources as although they are tapping a 'smaller' reserve of potential energy, they could be tapping more 'concentrated' sources of it.

So maybe solar isn't best... I'll shut up now



[ Parent ]
Wind (none / 0) (#103)
by dachshund on Thu Mar 06, 2003 at 08:26:17 AM EST

However as I wrote this I wondered whether wind/hydroelectric/wave power would be less wasteful of resources as although they are tapping a 'smaller' reserve of potential energy, they could be tapping more 'concentrated' sources of it.

Wind and wave power are certainly better if you live in a nothern country with poor weather.

However my problem is not with the concept of solar power, but only with the current implementations. At the moment there are no really practical, ready-to-sell solar power plants that can compete with modern wind turbines on cost and price. The only major solar panel installations that I know of are pathetically underpowered (a few MW here and there.) Other types of generation-- tower systems like the now-defunct Solar One-- are expensive and experimental. Whereas companies are looking to start building wind farms off Nantucket sometime in the near future, and Denmark derives 10-20% of its electrical power from wind.

[ Parent ]

Solar power.... (none / 0) (#105)
by olethros on Thu Mar 06, 2003 at 08:57:41 AM EST

looks unobtrusive, simple, and people have already seen it used - in pocket calculators. It is also the stuff that you see satellites use. Basically, it is simple: It is shiny, it does not have moving parts - it relies on an apparently reliable source - and there are consumer goods that use it.

The truth is that for large scale power generation, wind power seems to have more potential. Even in greece, where there is loads of sun, currently they are building pilot programs for aeolic power generation. Makes more sense. Solar power is good enough for residential use, I guess.

O/T: The solar-power-at-home scenario makes you independent from the power company. Exploiting wind power allows companies to remain in their traditional utilitiy provider role.

-- Homepage| Music
I miss my rubber keyboard.
[ Parent ]

Keeping things in perspective. (4.57 / 7) (#73)
by Verax on Wed Mar 05, 2003 at 06:31:52 PM EST

The fact is that to produce a megawatt of power will require at least 50 Power Buoys.

I'm glad that you pointed out how much is needed to produce 1 megawatt in terms of power buoys.  But I'd like to point out that the biggest wattages mentioned in your story were generally less than 10 megawatts.  To put this is proper perspective, consider the Diablo Canyon nuclear plant in California.  This consists of two units, which produce over 1,000 megawatts, each.
That's 50,000 buoys.  Those two nuclear units combined produce easily (and for real; they've been running since the mid 1980's) over 200 times the power of anything mentioned in your story, and take up a lot less space than windmills and buoys.

While I realize that no power source has 0 impact on the environment, the facts of the matter are that most of the power in the United States comes from burning coal, which releases huge amounts of radioactive material directly into the air.  Nuclear power plants are much friendlier to the environment than coal burning plants.  Although I do sometimes like to poke fun at the expense of the French, I do admire them for the foresight to switch their country to run on nearly 100% nuclear power.



----------------------------------------------
"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
Price comparison would be more useful (5.00 / 1) (#78)
by Keith Harper on Wed Mar 05, 2003 at 08:08:27 PM EST

When we talk about solar panels, we don't compare individual panels to nuclear reactors. It's a deceptive argument. It shouldn't be used in this case, either. Even if we assume that the buoys must be installed individually, it would be better to compare the effort required to install fifty thousand buoys to the effort required to build one nuclear reactor. Fifty thousand is just a number.

Also, you may be vastly underestimating land area requirements for nuclear power. They don't build reactors downtown, after all. Presumably there are specific regulations stating the minimum size of the area of unused land around the reactor, for safety and security purposes. Besides that, space requirements are a bullshit issue anyway. If we coated the Sahara in solar panels we could generate enough power for one hundred Earths. We have plenty of otherwise useless space for things like this. The ocean covers two thirds of the Earth's surface. Presumably there's enough space  to fit these generator buoys in somewhere.

The main problem with nuclear power is that it never really delivered on the promise of cheap energy. I'd be interested to know if it would be cheaper to install and operate fifty thousand buoys than one nuclear plant. To begin with, I suspect that they have much lower safety and maintenance requirements.

[ Parent ]

but in order to be useful (none / 0) (#81)
by modmans2ndcoming on Wed Mar 05, 2003 at 08:58:30 PM EST

bouys must be placed near shore and the number of shores with the correct properties are in the minority to the total area of the ocean.

I do like the sahara idea though :-)...perhaps we could do something liek this in the mojavi desert, that should produce all the power for the US.

[ Parent ]

May still be enough continental shelf space (5.00 / 1) (#91)
by Keith Harper on Wed Mar 05, 2003 at 11:07:11 PM EST

Saying that the area of ocean near the shore is a tiny fraction of the total ocean is a bit like saying that the size of the Earth is a tiny fraction of the size of the universe. It's absolutely true, but it tells us nothing about how much space exists for this sort of power. Solar power isn't quite cheap enough yet to make large scale solar schemes particularly worthwhile, but costs should come down rapidly over coming decades. If it winds up being as cheap as its advocates claim it will be, you won't need the green lobby to push the technology. Industry will be clamouring to invest in and build solar power. Call me cynical, but when that day comes, I'm sure there will be plenty of environmentalists decrying the impact of solar power on the desert ecosystem.

[ Parent ]
your not cynical at all.... (none / 0) (#93)
by modmans2ndcoming on Wed Mar 05, 2003 at 11:23:47 PM EST

they will need something to cry about.

[ Parent ]
the tech is here today...we just need to push hard (none / 0) (#94)
by modmans2ndcoming on Wed Mar 05, 2003 at 11:37:10 PM EST

to get it out sooner rather than later.

http://www.californiasolarcenter.org/solareclips/2002.01/20020108-5.html

[ Parent ]

The obvious solution (none / 0) (#99)
by ajduk on Thu Mar 06, 2003 at 05:17:09 AM EST

Is to mandate that all new roofing builds (new houses and replacements for existing roofs) have integrated solar generation, where they face a suitable direction.  Obviously you'd need a phasing in period, but this has the advantage of requiring zero additional space and producing power near to where it is needed.  The capital costs are somewhat offset by the fact that you are already putting a roof up.

If you make sure each building has a switch which can take it off-grid in the event of a grid failure, you can also sell it on security grounds - keep some lights/fridge/radio on in case of natrual disaster/terrorist incident.

[ Parent ]

Ye gods (5.00 / 2) (#109)
by Miniluv on Thu Mar 06, 2003 at 10:38:03 AM EST

Do we really need more government regulation concerning how we build houses? Do you realize that your argument regarding "offsetting capital costs" is utter bullshit?

A quick look finds me the cheapest panel available at Solar Electric is one made by BP with dimensions of 46.8" by 20.87". This unit costs $416.00 in lots of 16, which is the largest lot they sell in. Regular shingled roofing is dramatically cheaper, when you consider that sites such as this company in Reno give quotes for 1000 sq foot homes with 600 sq ft garages fully installed at under $2000, including labor.

Just to put that in a bit clearer perspective, each solar panel is roughly 7 sq feet, resulting in a need for approximately 228 tiles to cover the roof. That's $94,848 in solar panels, not counting the labor, or support systems required to actually HARNESS that power. Each solar panel generates a mere 85 watts. So, the entire roof (provided it could somehow all generate max power all the time) generates 19kW or so. According to numerous power company sites, including several co-ops, the average household uses roughly 16kW hours per day, so this roof would, at peak efficiency, provide a slight surplus of power. Electric companies charge, on average, around 7 cents US per kWh. This means you could live off-grid and recoup your investment in 84,685 days, or 232 years. I don't know about you, but I didn't plan on leaving my house in the family for four generations just to recoup the cost of a roof.

Now, I would love to see my numbers corrected, with an explanation of where I made my mistake. I am fully aware that I left a few details out, however as far as I can tell they're not more than at most a 5% or so deviance from the numbers I cited.

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]

Maths error. (5.00 / 2) (#117)
by ambrosen on Thu Mar 06, 2003 at 01:41:47 PM EST

You say an average house uses 16kWh per day, and the solar panels generate 19kW. So the panels take 16/19 of an hour to generate a day's electricity, i.e. 50 minutes. Given an average of 12 hours light a day, of which maybe 8 or 9 are near peak efficiency, then the roof is overgenerating by about 10 times.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]
Fair enough (5.00 / 1) (#126)
by Miniluv on Thu Mar 06, 2003 at 06:02:51 PM EST

However that doesn't actually make them any cheaper over the long haul, unless you put some form of storage facility, i.e. rechargeable batteries, which are going to jump your intiial investment rather steeply, in the neighborhood of $400-500/battery for deep cycle wet batteries.

Perhaps with a large enough initial investment you could live 24/7 offgrid, compensate for the non-sunny days, etc etc, and possibly recoup the investment in 15-20 years. Regardless, solar power is significantly more expensive over the average haul than buying power from the power company, and the original suggestion was ludicrous in the extreme.

Clean power must come from the power company, and not generally from the home user.

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]

Well, duh (none / 0) (#128)
by Keith Harper on Thu Mar 06, 2003 at 06:27:23 PM EST

Since peak energy consumption for houses is in the morning and at night, then obviously you need to store the power somewhere. Alternately, you can "sell" it back to the grid and use that to offset your energy expenses. I'm not an electrical engineer, so I don't know if that's possible, but it would be better than batteries. In any case, only the more overly enthusiastic supporters of solar power believe that it is ready to replace traditional energy sources today. It's still at only one third of its potential efficiency, and it's far too expensive. Once the price/output ratio becomes more favourable, solar power will probably be the number one choice for generating electricity, purely for economic reasons. That will take decades, though. One thing to remember is that there are probably economies of scale involved in the manufacture of solar panels. If demand increased, due perhaps to government regulation, then manufacturing costs for each unit could be expected to drop. This is the sort of thing government incentives can be good for. They can kick-start a market in a useful commodity where people just aren't aware of the potential. Of course, my preference is to wait for the advantages to become so persuasive and so obvious that only idiots aren't investing in them.

[ Parent ]
Formatting (Double duh on me.) (none / 0) (#129)
by Keith Harper on Thu Mar 06, 2003 at 06:28:56 PM EST

Since peak energy consumption for houses is in the morning and at night, then obviously you need to store the power somewhere. Alternately, you can "sell" it back to the grid and use that to offset your energy expenses. I'm not an electrical engineer, so I don't know if that's possible, but it would be better than batteries.

In any case, only the more overly enthusiastic supporters of solar power believe that it is ready to replace traditional energy sources today. It's still at only one third of its potential efficiency, and it's far too expensive. Once the price/output ratio becomes more favourable, solar power will probably be the number one choice for generating electricity, purely for economic reasons. That will take decades, though.

One thing to remember is that there are probably economies of scale involved in the manufacture of solar panels. If demand increased, due perhaps to government regulation, then manufacturing costs for each unit could be expected to drop. This is the sort of thing government incentives can be good for. They can kick-start a market in a useful commodity where people just aren't aware of the potential. Of course, my preference is to wait for the advantages to become so persuasive and so obvious that only idiots aren't investing in them.

[ Parent ]

Electricity consumption (none / 0) (#142)
by ajduk on Fri Mar 07, 2003 at 04:37:52 AM EST

Since peak energy consumption for houses is in the morning and at night, then obviously you need to store the power somewhere. Alternately, you can "sell" it back to the grid and use that to offset your energy expenses.

The second choice is a better idea; if you have a look at 24-hour demand, then you'll see that demand during daylight hours is around 20% higher than at night; this is basically industrial useage. So solar electric like this is generated when it is needed.

One of the problems in waiting for a market solution is, of course, the lead-in time; the project I envisage would have to be brought in over a decade or so.

[ Parent ]

Some modifications (none / 0) (#153)
by Miniluv on Fri Mar 07, 2003 at 11:37:24 AM EST

Your idea, as presented in the comment I replied to, is onerous in that its not an incentive its a requirement.

Energy credits, in some form, from the government to sponsor this might be an excellent way to encourage it, however the economics of current solar technology still appear to be pretty bad.

I suspect the best place to encourage the move to solar would be at the manufacturing and R&D stages. I know there is already some government funding in various nations going into the research of more efficient PV cells, and so forth, as well as deep cycle batteries and other storage technology for the excess energy produced.

Perhaps tax credits to builders who integrate a variety of energy efficiency enhancements into their new contruction projects would be an excellent way to create increased demand which would fuel production innovation and economies of scale to kick in.

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]

Selling back. (none / 0) (#150)
by ambrosen on Fri Mar 07, 2003 at 10:52:27 AM EST

In the UK, electricity suppliers are obliged to accept net billing, where you feed electricity back into the grid, and the amount billed is for (total consumed)-(total fed back into grid). A standard solar installation would include that.

It's interesting to note that the solar supplier that I've researched tends to advertise solar panels as cladding with the advantage of electricity supply, and for companies who wish to use the PR benefits. They have done installs on newbuild houses, though, and they do sell solar shingles which are the normal size for roofing tiles.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]

Numbers. (none / 0) (#136)
by Verax on Thu Mar 06, 2003 at 07:33:19 PM EST

When we talk about solar panels, we don't compare individual panels to nuclear reactors. It's a deceptive argument. It shouldn't be used in this case, either. Even if we assume that the buoys must be installed individually, it would be better to compare the effort required to install fifty thousand buoys to the effort required to build one nuclear reactor. Fifty thousand is just a number.

I did not compare an individual solar panel. I pounted out that you would need a huge number of them to compete with a nuclear power plant. Fifty thousand ceases to be "just a number" when it's a multiplier on something that you have to pay.

I get that the Diablo Canyon nuclear power plant consists of 2 units, produces about 2GW of power, would cost about $6 billion to copy, and produces electricity at US$0.03 / (kW hr).

So I ask: What are the corresponding numbers (for 2GW of power) for buoys? For solar panels? For windmills?

  • How many units?
  • Total cost to build?
  • What does the resulting electricity cost?
Perhaps we should take into account how big the footprint of the power sources are as well.



----------------------------------------------
"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
No, it's just a meaningless number (none / 0) (#138)
by Keith Harper on Thu Mar 06, 2003 at 09:19:16 PM EST

Yes. I agree absolutely with the statement that the necessary numbers are absent. What you don't seem to get is that the absence of necessary data is not an argument in your favour. We already know that nuclear power is economically unfeasible from that fact that it doesn't make money, and nobody wants to invest in it anymore. Not without considerable government incentives, anyway. That is an argument against nuclear.

[ Parent ]
Nuke plants are not modular (none / 0) (#86)
by guidoreichstadter on Wed Mar 05, 2003 at 10:16:29 PM EST

The modularity of a buouy system can be a big advantage, you know. Basically, you can start producing power with marginal investment, in whatever capacity you need, in say, a few months. A nuke plant takes years to construct, and you have to pay most of the costs up front before you realize any return. The absolutely huge capital, technology, infrastructure, social & enviromental costs associated with Nuke are a unsurmountable barrier to most of the societies in the world.

Plus, centralism can be a liability. Two hijacked airplanes can take two nuclear plants offline, or worse. Central power requires a large and costly national distribution system. Most importantly, though, centralized energy production reinforces totalitarian statist tendencies within any political system. Especially nuclear power, which almost guarantees that states will develop a nuclear weapons porgram.


you are human:
no masters,
no slaves.
[ Parent ]

They will be in 5 years (5.00 / 2) (#100)
by scart on Thu Mar 06, 2003 at 06:48:04 AM EST

South Africa is currently developing a concept known as the pebble bed reactor. It's basically radioactive material mixed with a neotron absorbing compound compressed into balls a couple of inches in diameter. You place a few thousand of these balls in a chamber, then use the resultant heat to drive a turbine. The compounds in the balls are mixed in ratios that prevent a runaway reaction from taking place, and the whole water cycle is a closed loop, to increase safety.

Each of the reactors is designed to produce between 20 and 50 megawats, and it's possible to build a number of them on the same site, with a staggered activation, as demand requires. The last figures I saw predicted that this design would drop the cost for a large nuclear plant between 50 and 80 percent.

This design will also make the handling of spent fuel much safer, and cheaper.

Regarding your last paragraph, South Africa had a nuclear weapons program during the apartheid era. It was stopped a few years ago, and all the remaining resources were moved into research into the civil applications of nuclear energy. The pebble bed reactor, as well as numerous advances in medicine and food preservation are direct results of that research.

[ Parent ]

But... (none / 0) (#108)
by cameldrv on Thu Mar 06, 2003 at 10:23:23 AM EST

The PBMR was on track before sept. 11 to be licensed and installed in the U.S. Exelon I know has expressed interest in the design. However, as I understand it, the PBMR design doesn't have a containment dome, as its safety is claimed to be good enough to not need one. Unfortunately, with the concern about terrorists flying airplanes into reactors, or attacking them by other means, four feet of concrete is looking like a minimum requirement to build a reactor in the U.S. This is if building any kind of reactor is even possible at this stage.

[ Parent ]
Safety (none / 0) (#143)
by scart on Fri Mar 07, 2003 at 04:43:10 AM EST

You are correct about the lack of a containment dome. However, that is an advantage. Traditional containment domes are extremely large structures, that are very easy to spot from the air. If an aircraft manages to crash into one, I am pretty sure that safety regulations will require the whole plant to be shut down until the dome can undergo an inspection for damage.

A PBMR however, is relatively small, and can be constructed underground. If one of the modules sustains superficial damage, it would still be possible for the rest of the plant to continue to generate electrisity.

As the events in California during the past couple of years have shown, new power stations is needed right now, not in 10 or 15 years time. Electricity generation from solar, wave and wind power will not a viable option in that timescale, and hydro power from large rivers isn't available in most areas. This pretty much leaves coal or gas fired conventional plants, and nuclear generation. With the stringent emissions control in the US, I don't think conventional plants have much time left before they are regulated beyond the point of being cost effective.

If the treat of terrorist attacks blocks the construction of new nuclear plants, then you are left with the unpalatable option of scaling down the usage of the available power. This will be an economic disaster. With no further hostile action from it's enemies, the US would be forced deeper into a recession that would take years to recover from.

[ Parent ]

Yes, it's a major problem (none / 0) (#145)
by cameldrv on Fri Mar 07, 2003 at 06:09:59 AM EST

Well, studies would have to be done about burying it in the ground, and its resistance to attack. However, not being able to easily spot it from the air is not much of a safety factor with GPS being available. I agree that we are facing a major energy crisis in the U.S. Oil and gas prices are through the roof. While oil is probably relatively temporary while Venezuela gets sorted out, and the Iraq situation is resolved, gas has been going up for several years. This will only continue to get worse as more gas fired plants are brought online. I thought that the tide was starting to turn on nuclear energy shortly before sept. 11, but it's much easier for politicians to just refuse to license plants than it is to make tough decisions about where our energy comes from. Supporting nukes now is, I believe political suicide.

[ Parent ]
You got that backwards (4.00 / 1) (#107)
by Miniluv on Thu Mar 06, 2003 at 10:08:21 AM EST

Find me a nation-state, or even a sub-state of a nation, which built a nuclear plant and then suddenly decided to start a nuclear weapons program. It just doesn't work that way.

The reason is that nuclear weapons programs require breeder reactors, which are no where near as efficient at producing power compared to non-breeder reactors. Why any state would choose to build some form of breeder to produce power alone is entirely beyond me. Instead most states (of the double handful on the planet which have nuclear weapons programs) started with a weapons program, and as a side bonus got some power. Most of the power produced in the breeder reactor typically goes right into fueling the program itself, as other stages of the weapons building process are also fairly energy intensive.

This is just another incoherent argument against modern nuclear power production techniques, and its not even presented terribly well. The genie is already out of the bottle when it comes to fission and fission-fusion-fission bombs, so trying to eradicate nuclear power with that argument is going to achieve jack shit. Argue against nuclear weapons, and recognize that nuclear plants do not equal nuclear weapons. Realize that nuclear weapons do not grow on trees, or in fields, or even in reaction chambers at power producing plants, but instead are always the result of a deliberate program put in place by some governing body.

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]

North Korea (none / 0) (#139)
by Keith Harper on Thu Mar 06, 2003 at 09:39:38 PM EST

What do I win?

[ Parent ]
I don't buy it...yet (none / 0) (#152)
by Miniluv on Fri Mar 07, 2003 at 11:31:14 AM EST

Everything I've read about North Korea's weapons programs indicate the power generation is just a perk and that weapons production was always the intent. However if you've got reliable evidence to the contrary that you can show, you'll get to see me eat crow (figuratively speaking of course).

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]
Circumstantial (none / 0) (#158)
by Keith Harper on Fri Mar 07, 2003 at 07:04:39 PM EST

They were willing to abandon their earlier nuclear reactor efforts, in return for help from the other nations in building modern reactors that don't produce enriched Plutonium. This suggests that, at some point, power generation was the primary issue. This makes a certain sort of sense, because North Korea is a nation that is very much at the mercy of sanctions and embargoes, and they probably want to reduce their reliability on things like coal, oil and gas. They'd still have to important nuclear fuel, of couse, but it stockpiles better.

[ Parent ]
Hmmm... (none / 0) (#175)
by Miniluv on Mon Mar 10, 2003 at 03:41:22 PM EST

That does lend a certain degree of credence to your argument that they stumbled into a nuclear weapons program through a goal of power generation, however I'm still going to say that its pretty certain that they made a conscious decision, at some point, to begin harvesting the enriched material, to machine the warheads, to develop the rocket technology and so forth.

North Korea is one of the worlds largest gun stores, and they decided to go that route very consciously. They're so sucessful at it because they're willing to sell just about anything to just about anyone, and they do so very deliberately. Perhaps they abandoned the nuclear weapons program, at one time, as part of a political ploy, but I don't think that Kim Jong-Il just woke up one day and said "Damn, we've got breeder reactors...why don't we build us a nuke."

"Too much wasabi and you'll be crying like you did at the last ten minutes of The Terminator" - Alton Brown
[ Parent ]

nuclear stations (none / 0) (#112)
by chu on Thu Mar 06, 2003 at 12:10:50 PM EST

I once met an architect who had designed UK nuclear power stations (I think in the 60's). They were told not to worry about the waste as there would definitely be methods for cleaning this up within the next 5 years at most. So the architects in the group believed the expert advice and made no provision for this. They thought they were building a bright new future (and some of the plants are still in use). In retrospect the architect felt completely used in a shortsighted political project and believes that nuclear power should stay in the lab until it is worked out properly.

[ Parent ]
What's your point? (none / 0) (#134)
by Verax on Thu Mar 06, 2003 at 07:02:37 PM EST

So, how does the fact that some architects were lied to in the 1960s have any bearing on whether nuclear power is "worked out properly" today?  I'm afraid I don't follow your argument.



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
my point (none / 0) (#148)
by chu on Fri Mar 07, 2003 at 09:52:08 AM EST

Waste is a problem that has still not been resolved and it is a fundamental problem not a detail as it was presented. I was giving a real world example of how even those on the inside were mislead and went on to create inadequate and dangerous designs as a result. I don't believe this is unusual at all. The point is that you should take any claims about nuclear power with a large dose of salt even when it comes from respectable sources as they may not have all the right facts.

[ Parent ]
Specifics, please. (2.00 / 2) (#161)
by Verax on Fri Mar 07, 2003 at 09:11:30 PM EST

Waste is a problem that has still not been resolved and it is a fundamental problem not a detail as it was presented.

By this, I am assuming you mean the problem of how to dispose of or store the waste. In the United States, there's Yucca Mountain, which is an excellent solution. But even without that, vitrified nuclear waste is still much less radioactive and hazardous than the slag piles outside of coal burning power plants.

I was giving a real world example of how even those on the inside were mislead and went on to create inadequate and dangerous designs as a result.

Very important questions, then:

  • How does where the waste is stored cause the design of the plant itself to be "inadequate" or "dangerous"?
  • What is "inadequate" or "dangerous" in the design of that plant?

The point is that you should take any claims about nuclear power with a large dose of salt even when it comes from respectable sources as they may not have all the right facts.

I agree that "respectable sources" shouldn't be blindly trusted in general. Still, if you have concrete evidence that the current nuclear power plant designs are unsafe, let's see your proof. A simple "I don't trust them, and neither should you" kind of argument is pretty weak without any support.



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
anecdote (none / 0) (#163)
by chu on Sat Mar 08, 2003 at 04:49:22 PM EST

Well we didn't get the blueprints out over the dinner table but she said something along the lines that she felt that the issue of waste should have been dealt with in the design of the plant rather than ignored. I guess she meant storage and reprocessing but I have no expertise in the area. This is just an anecdote after all. The point here is that a nuclear plant is highly technical and can be damn dangerous - and the public has to take it on trust that the people making them know what they are doing. When someone who has actually designed one of these things tells you that they wouldn't do it again because they no longer trust the facts they are given, you don't need to be a specialist to conclude that you might want to question your own trust also.

[ Parent ]
Appropriate use of Zero rating? (none / 0) (#176)
by Verax on Mon Mar 10, 2003 at 06:51:41 PM EST

Looks like billt gave the parent to this post a 0 rating. According to the Trusted User Guidelines:

Please use your "zero" rating with care! It is *only* for use on comments that are wholly content-free. If you think the poster is clueless, or an idiot, or you just don't agree with them, that is *not* grounds for a zero rating. Zero is for comments that are offensive, script-generated, or otherwise content-free and intended solely to annoy and/or abuse other readers.

My purpose in asking this is not to cry in my beer about a low rating, but rather to be clear on what the 0 rating is intended for. If my post really does deserve the 0 rating, what is the reason?



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
My favorite alternative energy source (4.50 / 4) (#74)
by edwin on Wed Mar 05, 2003 at 06:55:20 PM EST

The Solar Chimney. Frankly I have no idea if this is feasible or not - I just like the idea of building something a kilometre high. However some people down under are taking this seriously...

I think there was a test project... (none / 0) (#75)
by oldmanshands on Wed Mar 05, 2003 at 07:51:32 PM EST

In Spain IIRC, on a smaller scale obviously. It's definitely the coolest renewable energy idea I've seen - 1km high!

[ Parent ]
it looks like a plausable idea (none / 0) (#80)
by modmans2ndcoming on Wed Mar 05, 2003 at 08:52:01 PM EST

the only problem is the area that this thing would take up in order to generate enough energy.

I am a fran of using alternative energy to electrolicise water and package hydrogen. then evey home can have their own hydrogen fuel cell and every car can have its own fuel cell. then you can do 2 things, have a pipe connecting the home fuel cells to a hydrogen feed from a utility, or have fuel cells that use canisters or new metal hydrieds to have protable hydrogen for cars or remote fuel cells.

[ Parent ]

The area is usable (none / 0) (#84)
by guidoreichstadter on Wed Mar 05, 2003 at 10:05:07 PM EST

The area underneath the chimney was used in the Manzanares prototype was used as a greenhouse, so it's not wasted.


you are human:
no masters,
no slaves.
[ Parent ]
Not wasted... (none / 0) (#87)
by puppet10 on Wed Mar 05, 2003 at 10:18:31 PM EST

but this would only be feasable in areas with very low land costs since it takes several kilometer diameter roofs to produce 200MW compared to a coal plant which produces 500MW in a very small physical footprint.

Other than the sheer size of it (which is a problem common to most forms of solar or wind power) its an interesting idea.

[ Parent ]

HA- coal plants- small physical footprint??? (5.00 / 1) (#90)
by guidoreichstadter on Wed Mar 05, 2003 at 10:40:13 PM EST

I guess if you don't count the millions of acres of blasted mountaintops, destroyed forests and choked streams it takes to mine the coal ;P


you are human:
no masters,
no slaves.
[ Parent ]
Except... (none / 0) (#125)
by puppet10 on Thu Mar 06, 2003 at 06:01:31 PM EST

that area goes into providing coal for many many coal plants which can be placed in higher cost land areas near population centers (to reduce transmission losses).

The energy density of fossil fuels is much higher than than renewable sources, thus its still being used despite the inherent negative aspects of its use.

[ Parent ]

Too expensive blah blah blah (2.00 / 3) (#82)
by bjlhct on Wed Mar 05, 2003 at 09:00:47 PM EST

thorium blah blah blah hafnium blah blah blah spheral solar blah blah blah dense plasma focus

*
[kur0(or)5hin http://www.kuro5hin.org/intelligence] - drowning your sorrows in intellectualism
Interesting article (4.50 / 2) (#83)
by Kalani on Wed Mar 05, 2003 at 10:01:53 PM EST

You might try emailing my grandma. She was involved with the wave power experiment in Hawaii and can probably tell you more about how it's going.

-----
"Satan is the spiritual Microsoft of reality."
-- The Sociology of Cybers
Will do so (none / 0) (#102)
by imrdkl on Thu Mar 06, 2003 at 07:16:42 AM EST

Perhaps she will find my article helpful in her evaluation, although it looks like she's right on top of the situation. Thanks!

[ Parent ]
Gorlov helical turbine (4.33 / 3) (#89)
by guidoreichstadter on Wed Mar 05, 2003 at 10:36:26 PM EST

I read about the gorlov helical turbine recently, and have heard some follow up about a tidal project in S. Korea based on the idea. Basically, it's a meter/s long, lightweight submersible turbine configured to draw power from slowly flowing water bodies like streams and rivers, or tidal or wave motion, without the need for obstructing water flow with dams or culverts. It was designed in the mid 90's by Alexander Gorlov, a professor of engineering Northeastern University who helped design the Aswan High dam. It looks like it could turn out to be a very competitive, low cost modular system.


you are human:
no masters,
no slaves.
personally (1.00 / 1) (#95)
by Prophet themusicgod1 on Wed Mar 05, 2003 at 11:41:54 PM EST

i'm waiting for the 'matrix' style human-body-heat-combined - with-a-certian-type-of-fusion based energy.
"I suspect the best way to deal with procrastination is to put off the procrastination itself until later. I've been meaning to try this, but haven't gotten around to it yet."swr
Alternative energy will not produce enough power (5.00 / 1) (#110)
by Roman on Thu Mar 06, 2003 at 10:44:50 AM EST

This is why. Basically the guy is an engineer and he is analyzing the amount of energy that must be produced in terms of Gigawatt/hour, and he is showing that there is no viable alternative to what US is mostly using today - coal, gas, hydro, nuclear, oil. Nothing else generates enough power.

No numbers (none / 0) (#113)
by rusty on Thu Mar 06, 2003 at 12:48:43 PM EST

He doesn't show any numbers on the potential yields of alternate sources, so I'm not entirely convinced (either way, mind you), but it's an interesting argument nonetheless. His list of potential contenders especially was interesting. Thanks for the link.

____
Not the real rusty
[ Parent ]
You can use less, not only produce more (none / 0) (#121)
by Ximena on Thu Mar 06, 2003 at 02:22:55 PM EST

There many ways to use less energy without sacrificing confort. Most use of energy in individual houses goes to heating or cooling them or things inside. Better isolation, and using sun to heat water, for example, are very cheap and good alternatives. You can even use sun to cook food, which isn't practical in houses but not so much when you think in big instalations: use sun when there plenty, use traditional sources of energy in other cases. Then you have cars, besides using more public transport which in many cities are used to avoid trafic jam, you can use cell power, which need less oil. Of course, I am not sugesting you to the minimum use. This would be a real sacrifice.

[ Parent ]
Important quenstion about the cell. (none / 0) (#131)
by Verax on Thu Mar 06, 2003 at 06:35:46 PM EST

you can use cell power

What provides the power in the cell?



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
My favorite quote in his article (none / 0) (#122)
by mmealman on Thu Mar 06, 2003 at 03:27:51 PM EST

One person asked if I had researched new sources of energy; I don't need to

There's nothing like a well researched opinion.

[ Parent ]
That's a sobering argument (none / 0) (#124)
by imrdkl on Thu Mar 06, 2003 at 04:19:46 PM EST

Approaching defeatist. Sure there's some "big numbers out there", in terms of usage, but the available potential of alternative sources, and especially ocean waves, dwarfs them all. Iff the potential was not there, then I could understand giving up, and then I could applaud the pragmatism - but this is nothing but pure sloth.

[ Parent ]
Do tell... (none / 0) (#127)
by Verax on Thu Mar 06, 2003 at 06:25:09 PM EST

[...]the available potential of alternative sources, especially ocean waves, dwarfs them all

Can you back that up with some actual numbers?



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
Hmm, I though I did that in the article (none / 0) (#130)
by imrdkl on Thu Mar 06, 2003 at 06:35:24 PM EST

Multiply a hundred kilowatts per meter by the length of Australias coastline.

[ Parent ]
Energy questions. (none / 0) (#133)
by Verax on Thu Mar 06, 2003 at 06:58:04 PM EST

Multiply a hundred kilowatts per meter by the length of Australias coastline.

So, build nuclear reactors along the length of Australia's coastline.   I'm joking, of course, since they don't have to be there.  But you can get a lot more energy per square foot from a nuclear power plant than you can from anything else.  Plus, you don't have to build nuclear power plants in such selective locations.

Some questions for you:


  • Is all of Australia's coastline really capable of producing 100kw per meter?  (Per square meter?)

  • What is the caluclation that says you can get 100kw per meter? (I really doubt this, but would be really interested in seeing the math on paper.  I wasn't the best theromdynamics student, but this one should be pretty straightforward.)

  • I get that Australian coastline is roughly 20,000km.  Do you really think that building a structure longer than the great wall of China is practical for this purpose?

  • When I visited Australia recently, the word going around is that the great barrier reef is about to be much more strongly protected.  I don't think something counts as a credible potential energy source if it won't actually be permitted.  Do you?

  • Yes, nuclear power plants are expensive.  But what's the cost per meter that you would need to build along the length of Australia's coastline?

I think that in terms of cost of the produced electricity (US$0.03 / kW hr), the harm to the atmosphere (none), and the required space, nuclear really is cheaper, cleaner, and has less environmental impact than the alternative sources producing a comparable amount of power.



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
Much of this is covered in the article (none / 0) (#135)
by imrdkl on Thu Mar 06, 2003 at 07:26:19 PM EST

See the linked map in the final section for kw/meter potential around the coastlines of the world, and yes, most of Australia's eastern coast is rated at "100". For the pure math bits, have a look in particular at the Norwegian (NTNU) site, where two or three of their academic studies (including wave-math) are available in English. It's not terribly complicated, albeit somewhat dry.

The potential is sufficient, as Bellamy points out, to power most of Europe with about a hundred square miles of European coastline. I asked around a bit about Bellamy, while writing this article, and he's apparantly no idiot. Granted, it's only potential energy, but I'm not throwing in the towel just yet, and neither should you. :)

[ Parent ]

Actual requirements... (none / 0) (#137)
by goonie on Thu Mar 06, 2003 at 08:01:03 PM EST

According to some googling, my home state of Victoria's peak power demand is 8,000 MW. Assuming you can generate 0.1 megawatt per metre, that's 80,000 metres, so around 80 kilometres or 50 miles. Victoria's coastline is 1800 kilometres long, so you would have to have power stations along 4.4% of it.

Additionally, as well as a link to the New South Wales and South Australian power grids, we are currently building a link to the Tasmanian grid. Tasmania has 3,200 kilometres of coastline, much rougher seas (and consequently much more energy available), and a small population. Building them in Tasmania's rough seas and transferring across the link would probably be a net win.

So, in Victoria's case, we could certainly build these things and not put them in marine parks or anywhere too sensitive (assuming they don't totally fsck up the marine life). Queensland, as you point out, is a different matter. In any case, with the Great Barrier Reef blocking the waves there's no point in building wave power stations behind the reef!

[ Parent ]

Sloth is right (5.00 / 1) (#147)
by Phage on Fri Mar 07, 2003 at 08:38:59 AM EST

In just a few minutes, I have found some numbers that show that Geothermal energy is already producing 2700Mw in the US alone, and has the potential to produce 11,000 Mw. Seems like his biggest argument of scale has not been adequately researched !

However the main problem is still finding places of sufficient volcanic activity that Geothermal power is economically viable. This is where is reference to the "Core Tap" is relevant. However, I fundamentally disagree with his negativity.

I think that he has missed the point of alternative power sources. It will be a combination of renewables that will replace fossil fuels when the time comes. The correct solution for each state/town/nation will depend on the natural resources available to them. Iceland already obtains13-14% of the country's electricity generation, and 50% (PDF) of their total primary energy budget from geothermal energy.

For those of us who don't live on the slopes of a volcano, wind and wave may be the answer. For the swiss, they could afford fusion if anyone could.
The "USS Clueless" article smacks of a colossal arrogance.

I don't find Heathens to be sexy, as a general rule.
Canthros
[ Parent ]
Sorry: Alternative energy will produce enough powe (none / 0) (#166)
by boywonder on Sat Mar 08, 2003 at 10:10:21 PM EST

Remove the "not."

I disagree. The USS clueless sadly lives up to it's name. The arguments are vague and appear to be from a career naysayer.

Technology changes endlessly. Ideally it gets simpler and less volatile or dangerous. Energy production technologies are producing breakthroughs as we speak.

Living off the energy grid is so 20th century! Create your own home based system...

[ Parent ]

tidal power? (none / 0) (#132)
by atumai on Thu Mar 06, 2003 at 06:43:32 PM EST

Why can't energy be generated with tidal power by simply walling off a large area on the shoreline and making power with the displacement? Are the yields simply too low or something? How extensively has this been investigated? I suppose using natural structures (ie putting a dam across a bay) would lead to environmental woes.
-----
Disgust is an appropriate response to most situations. JENNY HOLZER.
Running the math on tide power. (none / 0) (#156)
by Verax on Fri Mar 07, 2003 at 05:04:43 PM EST

The problem with displacement is apparent if you look at the formula:

Power = force*distance/time

The lifting force for water can be pretty impressive; consider how much force it takes to keep an aircraft carrier afloat.  But the distance difference between high tide and low tide isn't usually very big -- something on the order of 15 feet.  Furthermore, the tide changes very slowly: one transition from low tide to high tide takes about 6.25 hours, and then there is another 6.25 hour wait for low tide to start over again.  In the end, the short distance and long time are more significant than the force.  

Say you had a buoy, which could support 1 ton.  If you put a chain on the bottom of it, and used the transition from low tide to high tide raise the buoy, pulling the chain, the pull on that chain could be converted to energy.  Power is not just how much energy is produced, but also how fast it is produced.  So, 1 ton of force acting through 15 feet every 12.5 hours gives 0.90 watts.  You'd need 110 of these contraptions to run a 100 watt lightbulb using the lifting power of the tide.  You'd need 2,200,000,000 of these to equal the power output of Diablo Canyon nuclear power plant.

The idea with wave power is that the waves come by more frequently than the tide changes, so one might expect better results than just the tide.  But how much power this can produce has still been misrepresented.

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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]

Think 3d [nt] (4.00 / 1) (#167)
by axxeman on Sat Mar 08, 2003 at 10:20:47 PM EST


Being or not being married isn't going to stop bestiality or incest. --- FlightTest
[ Parent ]

Maybe look at actual figures. (5.00 / 1) (#173)
by ambrosen on Mon Mar 10, 2003 at 07:39:47 AM EST

I'm not sure that anyone has ever actually proposed using buoys to harness tidal power for electricity generation. The only particularly large installation in use is the Rance barrage in Normandy, France, which generates 240MW, that is to say, about 12% of the nuclear power plant you're using as a baseline. That said, this (EU) report does say that in general tidal power is too expensive to be viable, and the resource is unevenly distribute within the EU, nearly all accruing to France and the UK. Also, of course, there are significant issues around tidal power, particularly given that it requires the blocking off of an estuary, and estuaries are hugely important wildlife habitats.

Also, I wonder whether you have any evidence that the potential of wave power is overestimated. After all, EU figures would seem to suggest that this is an abundant resource which can cover much of the electricity generation needs of some countries, although not currently at an economic rate.

--
Procrastination does not make you cool. Being cool makes you procrastinate. DesiredUsername.
[ Parent ]

Two errors here (none / 0) (#155)
by imrdkl on Fri Mar 07, 2003 at 04:47:41 PM EST

In the final section, when referring to Linda Johnson's article, I say it is from 1993, when she wrote it last January, 2003. Sigh. Also, the Piezoelectric streamers link should be removed. All of the available information about piezoelectric streamers is to be found in the other references.

I hope one of our esteemed site editors will show up and fix those.

Meaningful numbers? (5.00 / 1) (#157)
by Verax on Fri Mar 07, 2003 at 05:40:31 PM EST

In some areas (map) of the world, the ocean wave contains as much as 100kw of potential energy per square meter of wave-front.

So this says to me that when you have a wavefront passing by, you might get 100kW for each horizontal meter (the linked article does not say "square") on the face of that wave, if you could actually harness it. Right?

So, before we're all sold that wave power is wonderful, hows about some answers to some practical quastions:

  • Over how much time can that 100kW of mechanical potential be converted to electrical power?
  • If you're sucking the energy out of the wave, then at what point do you no longer have a wave?
  • How much time duration from one wave passing by until another wave passes by?
I think that when you take all this into account, you get much, much less than 100kW per square meter of ocean across which wavefronts propagate. If someone wants to show me the numbers, I'd like very much to see them.

Also, for purposes of comparison, the article compares power per square meter for sunlight to power on the face of a wave. That's a pretty "apples to oranges" comparison. How's about the average power per square meter over the regions of water where the buoys will be? If it can't beat out the 100 watts per square meter claimed for solar, then solar then where's the advantage?



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
Fair questions, and a valuable correction (5.00 / 1) (#159)
by imrdkl on Fri Mar 07, 2003 at 07:19:48 PM EST

And your correction was sorely needed. (editor, note this please, along with another small correction below.)
So this says to me that when you have a wavefront passing by, you might get 100kW for each horizontal meter (the linked article does not say "square") on the face of that wave, if you could actually harness it. Right?
Correct. The "square" in that sentence should be replaced with "linear". The number actually refers to kW/m Crest Length, and a better map is to be found in the WEC Survey which I also linked above in the references. Anyhow, if you have a look at the map, the 100 kW/m (linear) refers to only a few specific coasts of the world, although every coast has a tremendous potential, at 50, or even 20 kW/m. This indeed does make wave power much more readily available and consistent than either wind or solar.
Over how much time can that 100kW of mechanical potential be converted to electrical power?
This question is not clear to me. Are you referring to lag, or consistency, or? Please clarify.
If you're sucking the energy out of the wave, then at what point do you no longer have a wave?
According to my limited research, this question is fundamental to the field of study in general. A popular quote in the scientific works I read about wave power is, "A good wave-absorber must be a good wave-maker". That is to say that, when capturing the wave, water must be displaced in an equal and opposite (oscillating) way to maximize absorption. It can be shown theoretically, according to the Norwegian scientists (also linked in the article), that 50% is the maximum amount of power that can be harvested from any wave, and that makes sense in light of the requirement for a wave-maker.
How much time duration from one wave passing by until another wave passes by?
This problem was also mentioned in the article. Optimizing calls for "guessing", not only the frequency, but (more importantly) the amplitude of approaching wave. To do this, two techniques are used, one estimates directly by the depth of the trough in front of the approaching wave, and the other uses realtime data. These are also discussed as important innovations by the Norwegians in 1993. Presumably, the OPT implementation still doesn't have them quite right, but that doesn't change the potential.

I also found, but did not link this article which compares and contrasts two specific types of buoy devices, and discusses in significant detail the nature of optimizing wave capture in general. There are plenty of other considerations, related to harmonics, and buoy-shape, and more. Some devices, like the salter duck, have approached the target of completely "nullifying" the incoming wave, but efficiency is lost in the capillary pumping action which is built into the duck.

Anyways, I didn't want to drone on too much here, but thanks for the correction. The mistake was unintentional.

[ Parent ]

Total energy vs. Power (I guess)? (none / 0) (#160)
by Verax on Fri Mar 07, 2003 at 08:08:10 PM EST

I asked:Over how much time can that 100kW of mechanical potential be converted to electrical power?

You asked: This question is not clear to me. Are you referring to lag, or consistency, or? Please clarify.

Sorry for the poor question. I don't have the understanding and/or vocabulary for this sort of thing. So, rather than try to ask a better question, I'm going to babble a bit in the hopes that you'll see what I'm missing.

Suppose that the best of the buoys is sitting in the water. A wave with 100kW per linear meter of crest length propagates into the area where the buoy is floating. How long does it take for the wave to propagate all the way past the buoy so that the buoy can no longer harvest energy from the wave? Or, does the buoy drain all (or essentially all) of the energy from the wave, so that there is no wave remaining to continue propagating?

As a dumb example, let me pull numbers out of the air and say that the buoy is 20 feet long (in the direction of the propagating wave). Once a wave comes along, I'm guessing that when it first hits the buoy, there's 100kW of power for that small period of time. But then, say, a second later, the wave has propagated another 5 feet, and has less total energy than it initially did. So does the wave now have 75kw mer meter? By the time the wave reaches the end of the buoy does it have any energy left? How long does the buoy then have to wait (on average) for the next wave to come along?

Is the following reasonable?
average_power = energy_in_average_wave * fraction_of_energy_harvestable / peak_to_peak_time_between_waves

  • how much time duration from one wave to the next?
  • how much total energy is in a single wave (per meter of crest)?
  • what fraction of energy in a single wave can actually be harvested?

I guess what I'm getting at is that a jillion watts of power isn't meaningful unless it can be provided continuously over some length of time. If it's only there for an instant, the total energy transfer might not be much. How can we turn the "100kW/m" into an reasonable number for average continuous watts (The wave can't produce that 100kW/m forever, right?)? Thanks for bearing with me, and apologies if the answer to all this has been sitting there in an obvious place all along.



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"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
Waves are continuous (none / 0) (#162)
by imrdkl on Sat Mar 08, 2003 at 04:33:48 PM EST

Either the buoy is going up, or it's going down. This continuous process drives a secondary continuous process, which is the piston and pump, these drive yet another continuous process, which is the undersea turbine. After all that, the turbine drives the generator. The process is continuous as long as waves are coming.

The difference between wave power, and other forms of continuous power like wind, is the number of intermediete (continuous) processes which are required to get the turbine spinning.

[ Parent ]

Continious waves. Really? (none / 0) (#170)
by Verax on Sun Mar 09, 2003 at 01:51:07 PM EST

Waves are continuous [...] Either the buoy is going up, or it's going down.

I don't know much about waves around the world. My limited experience with surfing is that waves come in sets, and that there is some dead time between one wave and the next. Floating on the surfboard, it can be going up or down, or just sitting there, waiting for the next wave.

So what I'm asking is, in these areas that have the 100kW / m waves, how long do you have to wait between waves? In those areas, are they really continuous? Perhaps they are; I'm just asking because that does not match my observations.



----------------------------------------------
"It is a poverty to decide that a child must die so that you may live as you wish." -- Mother Teresa of Calcutta
[ Parent ]
Have you ever surfed (5.00 / 1) (#171)
by imrdkl on Sun Mar 09, 2003 at 03:33:05 PM EST

A kilometer offshore? In water 50-100 meters deep? Things are different out there. Recall your last deepwater boat trip in a storm - regular as clockwork.

In any case, the buoys are staggered over a wide-ish area, and they're all hooked together to drive the same pump. While one is going up, another is going down. The average wave periodicity for a given site determines the amount of coverage required to assure the turbine spins regularly.

[ Parent ]

Correction (5.00 / 1) (#172)
by imrdkl on Mon Mar 10, 2003 at 03:36:09 AM EST

The individual pumps which are attached to each buoy drive a common generator.

[ Parent ]
Micropower (5.00 / 1) (#165)
by boywonder on Sat Mar 08, 2003 at 10:00:08 PM EST

I really appreciate this thread, and as always, the intelligence of k5 posters.

One thing that the article doesn't really mention is a very sane, decentralized solution - Micropower.

Micropower generally is a term used to describe home based systems, whether they be solar, wind, electromagnetic (in development) or similar systems.

Ideally, in the future, groups will convince housing developers to include micropower systems in the contruction of the homes. At this point, solar systems can be expensive (10-15 grand) but wind can be cheaper and easier to use.

However, if you include this relatively small chunk of money in the price of your new home it's not so bad...

The goals of micropower are obvious. The side effects are better.

1. If you choose to stay connected to the conventional power grid, many utilities will pay you to feed unused kilowatts into their systems.

2. No power outages.
3. No electric bill.

4. Hopefully the future reduction in numbers of tumor causing hi wattage power lines, etc.

I'm probably starting to sound like I work for Ernie's solar shack. I don't. But, the potential for micropower to relieve the common person from the headaches of worrying about how their power is generated is great.

Similar systems could easily be implemented in apartment complexes and office buildings.

This, my friends, is the wave of the future.

I like it too (none / 0) (#169)
by imrdkl on Sun Mar 09, 2003 at 09:23:22 AM EST

And it was discussed in a recent article, as well.

[ Parent ]
"tumor causing high voltage power lines" (none / 0) (#174)
by jforan on Mon Mar 10, 2003 at 01:39:42 PM EST

funny.

Jeff
I hops to be barley workin'.
[ Parent ]

Catch a Wave: Profitable Alternative Energy? | 177 comments (149 topical, 28 editorial, 0 hidden)
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