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Is long-distance electric power transmission realistic?

By redelm in News
Wed May 09, 2001 at 01:13:34 AM EST
Tags: Technology (all tags)

In the news with California rolling blackouts are stories of power transmission from as far away as Canada. Is this really a solution, or are losses really too high and all the talk is a political band-aid?

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comments (24)
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I had always heard that electric power transmission and distribution was horribly inefficient, and that true long-distance(>1000km) power transmission suffered impractically high losses. But the only example I can find (PDF here) (Google HTML here?) shows moderate losses of 0.0036%/km, or ~50% over 2000 km. This is borderline unacceptable, but in Calif it might be that or the unthinkable (starting up old power plants).

Of course this is just an example. Conductors could be bigger or smaller. Or already loaded and some step-up transformers would be certainly needed along the way. And the routing might be as complex as the Internet since I doubt there are idle long transmission lines all along the ideal (shortest) route. It might be as bad as going from San Francisco to Washington DC pre-Interstate, an experience that the young Lt. Eisenhower had and led him to build the Interstate Highway System as US President. Power lines are very expensive and the right-of-way hard to acquire, so I doubt they're built to sit idle. Lines help fill-in when power generators are off-line for maintenance (once per 1-4 years?), but I suspect it's cheaper to build multiple generators and bring one down at a time than to build mostly unused transmission lines.

Of course we all see the pylons and transmission towers and figure they must be good for something. But are they really useful to get California out of the shortages? Or is NIMBY a delusion, and all the talk of importing distant power a politically generated distraction? Does anyone have a good understanding of the long-distance power grid?


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I think the Calif power shortages are:
o Created by evil power companies 19%
o Created by the Prince of Darkness [Grey Davis] and his henchmen [politicians] 29%
o Created by the laws of physics 11%
o solvable by other states not hoarding their power 2%
o solvable by banning MS-Windows9* [Linux|FreeBSD save power] 17%
o solvable with more deodorant [conservation] 17%

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Is long-distance electric power transmission realistic? | 55 comments (53 topical, 2 editorial, 0 hidden)
pipedream (1.71 / 7) (#1)
by 2400n81 on Tue May 08, 2001 at 12:10:20 PM EST

yea or maybe carry electricity thru the air like Nikolai Tesla.

yea there is NIMBY going on here. just wait till the stupid NIMBYites die off from cancer from the giant electromagnetic relays from some anonymous State's power needs.

california sucks. move away while u still can.

It doesn't work that way (4.00 / 5) (#2)
by YesNoCancel on Tue May 08, 2001 at 12:15:51 PM EST

Actually, the electric power would not be sent from Canada to California directly; this would be highly inefficient. Long-distance power transmission works by "handing" the power from country to country and from state to state, so the power generated in Canada would flow into the states along the northern U.S. border, the power plants there would transfer the amount of power received from Canada south to the next state, and so on.

This kind of long-distance electricity trade is quite common in Europe, where electric power is traded between member states over long distances.

Chaining is still transport (3.00 / 1) (#8)
by redelm on Tue May 08, 2001 at 01:06:25 PM EST

Yes, I realize that the power isn't directly transfered. It's moved from one sub-grid to another and another. But the net effect is the power is transferred the whole distance from suprlus grids to deficient grids. Some of the links may be efficient, some may be less so.

[ Parent ]
But the loss is different. (none / 0) (#15)
by jabber on Tue May 08, 2001 at 02:09:44 PM EST

YNC made the point very clear though, that generated electricity doesn't travel all that far. This is good from the loss perspective, because you are not in fact transmitting power 2000 miles, with a 50% loss... You're transferring it a few hundred miles tops with significantly less loss.

So if Canada sells their power to Washington, which then sells their power to Oregon, which then sells their power to California, there's significantly less loss than if Canadian power was routed and sold directly to California - and many more middle-men make a profit along the way. ;)

So YNC is correct in whose power goes where, and you are correct in that the net effect is that a Canadian surplus makes it possible to fill a deficit in California, but there is not a direct transmission of power between CA and CA (huh..) which is an important point.

[TINK5C] |"Is K5 my kapusta intellectual teddy bear?"| "Yes"
[ Parent ]

There are still losses along the entire route (none / 0) (#22)
by redelm on Tue May 08, 2001 at 04:21:30 PM EST

I'm sorry I didn't make myself clear. I agree the power isn't sold very far away, and doesn't incur much loss on this first step.

But there are many subsequent steps, and each incur loss unless there was a previously northward flow that gets reduced by supply from the north.

I'm presuming that all these negative losses have already been pulled out of the system by California. And that the grid already had little northward flow due to hydropower in Washingto. Or is this not so?

[ Parent ]

Loss rate (none / 0) (#24)
by jabber on Tue May 08, 2001 at 04:41:23 PM EST

It has been several years since I did anything even remotely related to this sort of thinking, so I might be talking out of my arse. If anyone with more current knowledge could sanity chack the following, I would greatly appreciate it:

IIRC: The short distance transmission losses, with consumption and regeneration of the transmitted power, will provide a loss rate that would approximate a linear one in the end-to-end transmission.

A direct transmission loss rate is not linear. I forget whether it is a square function, or if it exponential, but it is certainly less efficient than linear.

So it makes much more sense to transmit power in relatively short distance hops than in one long wire. This is from the EM physics perspective alone, without considering the economics of multiple transfers, cost of production per region, various rates at which power can be sold, and whatever else the business conditions are.

This is similar to data transmission, where a signal degrades unless sent through repeaters. The cost of the repeaters and transmission media needs to be taken into account when designing a network, just as the signal strength does - but when considering networking theory, cost doesn't really factor into the material.

[TINK5C] |"Is K5 my kapusta intellectual teddy bear?"| "Yes"
[ Parent ]

Sanity checking those figures (5.00 / 1) (#34)
by squigly on Wed May 09, 2001 at 07:50:55 AM EST

I've never done anything on this topic, but your figures look about right.

The short distance transmission losses...a loss rate that would approximate a linear one in the end-to-end transmission

A direct transmission loss rate is not linear. I forget whether it is a square function, or if it exponential, but it is certainly less efficient than linear.

Must be exponential surely. You lose a percentage per metre.

Sounds about right. Lets look at a toy example - 2000km = 50% loss, so to send 1000W of power, we would need to generate 2000W in Canada - total surplus of 1000W.

If, on the other hand we have 2000 hops of 1km, we need to generate a surplus of 0.36W per station. A total extra requirement of 720W. Not an astounding benefit.

Of course, this is just a toy example. YMMV.

[ Parent ]

Think about what you are saying (none / 0) (#26)
by jungleboogie on Tue May 08, 2001 at 05:16:20 PM EST

It isn't the same power from Canada to California!!!

It is simply a game of equivalency. The power which is received in one area is re-generated and sent down the line.

[ Parent ]
Superconducting possible (3.50 / 2) (#3)
by weirdling on Tue May 08, 2001 at 12:16:58 PM EST

Although it would be a great expense, building a superconducting power transmission line from, say, Nevada, to California is a possibility. It would be extravagantly expensive to build, but would probably pay for itself quickly as more and more power goes through that conduit.

I'm not doing this again; last time no one believed it.
ACK!!! (4.00 / 1) (#16)
by minusp on Tue May 08, 2001 at 02:13:33 PM EST

A great expense, you say... understatement of the year, here...

I used to be in "the biz" and let me tell you, as things stand now, there just ain't no way it's gonna happen. Period. There are no mass producible conductors that will run more than a handful of degrees above 0°K, so liquid Helium is the refrigerant of choice, expensive, to say the least, and the _thought_ of a cryostat a couple of hundred miles long is boggling...

I wish that hi-temp supercons _did_ exist, the amount of energy we waste as heat is obscene.
Remember, regime change begins at home.
[ Parent ]
High Tc superconductors (4.00 / 1) (#29)
by sigwinch on Tue May 08, 2001 at 05:55:14 PM EST

Don't remember where I saw it, but I thought you could buy power cables made from the newer high-temperature superconductors, which can use liquid nitrogen as the refrigerant. In fact, I remember reading articles about them already being in use for short-haul lines (a few miles or less). Of course, no matter how good the high-Tc materials get, a 100 km line would still be outrageously expensive.

I don't want the world, I just want your half.
[ Parent ]

Still... (5.00 / 1) (#48)
by minusp on Thu May 10, 2001 at 09:31:55 AM EST

Manufacturability and utility are the keys... AFAIK, the newer S/Cs that are approaching hi-temp are ceramic based, ie., NO ductility == NO flexibility == not a real good _wire_ you got there, bud. This is the problem with Nb3Sn now, really good conductivity for induced field strength(high JxB)but fragile as hell. NbTi is really good and ductile (I've even welded it to make truly persistent [0.0E-20 ohms] joints in the wire, but suffers from lower current limits, and needs more Coldness to be happy. The tradeoff seems to be usefulness _as wire_ versus current/temp capabilities.
And yeah, even a 100 km LN2 cryostat would make NASA look cheap... never mind LHe...

Remember, regime change begins at home.
[ Parent ]
superconductors (none / 0) (#52)
by sigwinch on Fri May 11, 2001 at 05:26:46 PM EST

True, true, the ceramics suck. One way I heard to deal with the fragility was by making tiny whiskers of ceramic, silver plating them (?), and then lining them up in a sheath. Funny thing is, this counts as a major improvement over tubes filled with ceramic powder. Such is slow development of this technology.

I don't want the world, I just want your half.
[ Parent ]

The power crisis. (4.50 / 8) (#4)
by ucblockhead on Tue May 08, 2001 at 12:20:33 PM EST

The California power crisis is not a shortage. It is entirely political. Technical solutions aren't going to do a damn thing.

(And the man's name is "Gray" Davis, and since this was a problem long before he took office, no one blames him for the problem. (Blaming him for lack of solutions is another matter.) )

It is political aspects:

  1. Embarking on a poorly thought out privitization scheme primarily because it was the buzzword of the day.
  2. Refusing to build power plants where anyone objected.
  3. Closing down plants because of objections from environmental groups. (In theory a good thing, but when combined with (2), deadly.)

This is k5. We're all tools - duxup
More importantly (4.75 / 4) (#6)
by Simon Kinahan on Tue May 08, 2001 at 12:39:24 PM EST

1. Capping the price the utilities could charge to consumers, but not the wholesale price, in apparent defiance of the laws of arithmatic.

2. Preventing the utilities from using derivatives to offset risk, meaning they had to pay spot market (ie. "can we have more power now please ?") prices to generators.


If you disagree, post, don't moderate
[ Parent ]
Privitization and Canadian Electricity (3.50 / 2) (#13)
by Mad Hughagi on Tue May 08, 2001 at 01:42:19 PM EST

There has been quite a buzz lately in the Canadian province of Ontario with regards to utilities privitization. The provincial government recently privitized the entire power generation juggernaut (hydro, nuclear, fossil fuels, etc etc). There has been quite a bit of debate as to whether this was a good move.

Looking at how the California situation has developed, many people (mostly people who are working for the new "privitized" power generation companies that used to work for the public company)are fearing the same kinds of problems as California is facing now. It will be an interesting situation to follow. If the same kinds of problems turn up in Ontario as in California there will definately be some reluctance for other regions to follow the privitization approach.

As a side note, mass energy transfer from Canada to the United States is nothing new. If Quebec didn't operate such a large hydroelectric dam network I don't think there would be too many lights on in New York. While I'm not in the mood to go looking for numbers, I'm fairly certain the distances from the generation facilities to New York city are on the order of 1000 km. It's economically viable there, so I don't see how it wouldn't work in California.


We don't make the products you like, we make you like the products we make.
[ Parent ]

Devil's in the details (5.00 / 3) (#17)
by ucblockhead on Tue May 08, 2001 at 02:14:48 PM EST

From what I understand, England did much the same, and had a good experience. The trouble is that you've got privitization advocates who claim that any privitization is good and privitizaiton opponents who claim that any privitization is bad. They are both wrong. My primary opinion is that power in California was not an issue ten years ago. It was an issue of "if it ain't broke, don't fix it". If I were an Ontario resident, I'd ask myself whether or not it is broken, and what the province wants to get out of privitization.

The even more important thing is that all "privitization" is not equal. The details of the way it was done in California were idiotic.

Anyway, the question isn't whether or not it is viable to ship energy from Canada to California because the root of the issue is that the entity (PG+E) that is suppose to pay Canada for energy, and ship it to me, a consumer, is bankrupt. They've got no money to pay you. Hell, if I were Canadian, I wouldn't want to sell California companies power, because there's a damn good chance you won't get paid.

What is disgusting about all this, of course, is that California has just gone through a huge economic boom. The state government is rolling in cash. The parent companies of the power deliverers are rolling in cash. The power generators are rolling in cash. But because the system is economically screwed up, one company central to power delivery is bankrupt, and that can cause my lights to go out at any moment.

In essense, here's what happened. The state said that the power generators could charge whatever they wanted. The state put limits on what the power deliverers (like PG+E) could charge the consumers. The generators quickly figured out that shutting down plants (and reducing supply) increased the price they could charge, and thereby their profits. The parent companies of the deliverers, like PG+E Corp sucked the cash out of the deliverers and then put legal mechanisms in place so that they would not be liable for the bankrupcties that were coming. (ie they new damn well that was coming.) Since PG+E was selling power at a loss, it quickly ran through its cash, and thus has no money to buy power.

The upshot of all this is that some people (notably, the power generators) are making a whole hell of a lot of money, while California consumers are having to pay higher and higher bills in vain attempts to prop up PG+E.

This is NOT in any way a technological problem. It is entirely political and economic, and how much it costs to ship power from Canada to California is just not relevant. The issue is only whether someone in California will be able to pay to receive it.
This is k5. We're all tools - duxup
[ Parent ]

A small point (none / 0) (#21)
by dzimmerm on Tue May 08, 2001 at 04:20:42 PM EST

If Canadian power companies provide power to California then they are in essense competing with the local power generating companies.

Could this posibly provide incentive for the local generating companies to lower their costs? Privatization should work if competition replaces a regulated monopoly. Without competition the situation is untenable as there is no incentive to give the consumers a fair deal.

If the exchange rate comes into play the cost of Canandian generated power should be less if no allowance is made for the greater distance and loss due to the tranmission medium.


[ Parent ]

"local" generating companies (5.00 / 1) (#27)
by ucblockhead on Tue May 08, 2001 at 05:33:40 PM EST

A lot of the power is generated out of state, actually.

Part of the problem is the way that PG+E has to buy power. They are restricted to buying it as needed, and can't make deals. It doesn't take a genius to figure out that the power generators can essentially extort higher fews simply by saying "no" a few times before giving in. More power from Canada certainly would help that, as you say, but whose to say Canadian companies don't start doing the same? But more importantly, because PG+E has to buy on the spot, it is susceptable to emergencies at the generators. Like heat waves in Texas or (potentially) cold snaps in Canada. The spot buying makes prices spikes worse.
This is k5. We're all tools - duxup
[ Parent ]

Borderline unacceptable? (4.00 / 5) (#5)
by Alias on Tue May 08, 2001 at 12:20:43 PM EST

moderate losses of 0.0036%/km, or ~50% over 2000 km.

This means that, at 2000 km., you need to produce twice the energy.

You call this "borderline unacceptable"?..

To think the Powers That Be also want to liberalize the Swiss energy market... *shudder*


Stéphane "Alias" Gallay -- Damn! My .sig is too lon
*cough* Minor mistake (none / 0) (#9)
by Signal 11 on Tue May 08, 2001 at 01:11:41 PM EST

I'd like to point out that that is cumulative, like compounded interest rates. You can't simply add percentages together like that.

The answer is much worse than that too, btw. :)

Society needs therapy. It's having
trouble accepting itself.
[ Parent ]

Oops, slipped a decimal: 0.036%/km (5.00 / 1) (#11)
by redelm on Tue May 08, 2001 at 01:32:01 PM EST

The numbers from the example are 5.44 kW/km loss for 150 MVA transported over a set of Drakes.

Cumulative losses then calculated as 0.99964^2000, not as 0.036%*2000=72%

[ Parent ]

Some facts... (3.33 / 3) (#7)
by Signal 11 on Tue May 08, 2001 at 01:05:35 PM EST

The closest city to Los Angles (California) on the Canadian border is Vancouver, BC. That is about 1276.0 miles away, or 2053 km for you metric folks. The voltage on high power lines is anywhere from 230kV to around 750kV, if memory serves. Unfortunately, I do not know for certain what size wire they would use and how many lines they would use, so I will need to guess...

0000 gauge wire has 0.0490 ohms per 1000 feet. This gauge wire is very large, it is 11.684 mm in diameter.

We know LA is 2053 km away, but we need to find the total impedance for the wire over this distance. The distance in feet is 6,735,564, or 6736 "kilofeet". 6736 (feet) times 0.0490 (ohms) gives us 330 ohms of 'line resistance' for the circuit. Additional resistance can come from heat, and due to the fact that the wire would be so long, it'll likely have induced voltages in the tens of thousands of volts during solar flare activity. But we don't care about that for now. :)

Now, 0000 wire can only handle about 282A max. 330 * 282 (ohm's law), which means the voltage on the wire would be 93kV.

282A @ 93kV is about 26,319 kilowatts. My home sucks about 24 kW, if my math is right, so that's enough power for about 1,096 homes. This is a *best case* scenario.

Just some food for thought....

Society needs therapy. It's having
trouble accepting itself.

Check the link! (4.00 / 1) (#10)
by redelm on Tue May 08, 2001 at 01:14:45 PM EST

Power transmission is done on sets of three conductors, carrying the X-, Y- and Z-phases. The wires themselves are steel cores for strength with aluminum wires wrapped outside for conductivity. Interestingly, the different wire sizes are named for birds!

And resistance isn't the only problem -- you also have large inductive losses and corona problems at the higher voltages (hence 4 spaced smaller conductors on some lines).

[ Parent ]

Ahem (none / 0) (#18)
by jabber on Tue May 08, 2001 at 02:15:30 PM EST

Power transmission isn't direct. It's a hand-off system where one grid pours into another grid. The power from Grid A is used up in Grid B, whose generating capacity is fed into Grid C, and so forth.

Your math may be correct, but it assumes something that is not true.

Yes, in theory, your tax dollars pay for the stealth bomber... But they are not the same bills. See how it works?

[TINK5C] |"Is K5 my kapusta intellectual teddy bear?"| "Yes"
[ Parent ]

Don't think so... (5.00 / 1) (#36)
by gordonjcp on Wed May 09, 2001 at 09:18:02 AM EST

I think you've just worked out the voltage drop over the line.
So, 330 ohms *PER PHASE* - if you worked it out over a single phase as you have, the loop resistance would be around 660 ohms. This would mean a voltage drop of 93kV per phase - this means that in a 275kV circuit you'd get 180kV or so per phase.
You could use a suitable transformer to allow for that.

Give a man a fish, and he'll eat for a day. Teach a man to fish, and he'll bore you rigid with fishing stories for the rest of your life.

[ Parent ]
Ummm a couple things. (none / 0) (#37)
by tzanger on Wed May 09, 2001 at 11:38:51 AM EST

First, you calculated the resistive losses for one phase, not three. Also you need to take into effect inductive losses and corona effects since it's so long a distance. Others have pointed this out.

The fundamental problem I see in your calculation is that for long-haul links they actually rectify the voltage and shoot millions of volts DC and then chop it back to AC. One of the engineers at the company I work with was at a large rectifying facility -- they used thousands of series-connected hockey-puck style diodes to build up enough reverse blocking voltage and he claims the entire building had an "eerie tingling feeling" to it. The rectifier chains ran overhead and the ancilliary equipment was on the cement floor.

I've never seen this personally but I am failry (95%) sure that DC is used for long-haul transmission because it is actually more efficient than AC, as the current travels through the entire conductor, among other reasons. The problems are the rectification and chopping at either end.

[ Parent ]
GAH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! (none / 0) (#49)
by Signal 11 on Thu May 10, 2001 at 07:38:53 PM EST


For God's SAKE, Nikkoli Tesla figured this out back during the 1800's!

Society needs therapy. It's having
trouble accepting itself.
[ Parent ]

Instead of blindly believing what you read... (none / 0) (#51)
by tzanger on Thu May 10, 2001 at 09:23:15 PM EST

Why don't you do some further research?

Here is a link to an HVDC chapter in a power electronics course at the University of Missouri. In short: HVDC economically cheaper than HVAC when it comes to long distance transmission and, as a direct quote from that introductory page claims: With an HVDC system, the power flow can be controlled rapidly and accurately as to both the power level and the direction. This possibility is often used in order to improve the performance and efficiency of the connected AC networks.

Now as I'd said in my first post and is backed up by the tutorial in the link above: DC transmission does not suffer reactive losses. Over large distances these losses can and do build up to become a large factor in your loss calculations. Also, unlike alternating current, DC will flow through the entire conductor instead of along the outer surface.

Now while I have not investigated the actual depth that 60Hz AC penetrates aluminum wire I do know that it is small enough that the high tension lines are specially made to take advantage of this. High tension cable has a steel core and then an aluminum outer layer to minimize the transmission losses and maximize cable strength. I'm not sure what they use for DC links but I imagine they will use solid aluminum wire and space the towers closer together. I'm not sure on this.

Furthermore, your claim that Tesla proved DC to be inferior at long distance transmission in the 19th century is only partially true. AC is more efficient for conversion and short-haul transmission: it's ability to be almost perfectly stepped up and down is wonderful and the AC motor is almost a 100% (98% efficient motors are sold every day) efficient electrical to rotating mechanical convertor. However as this link shows, Tesla also did recognize that DC was more efficient for long distance power transmission.

Lastly I refer you to this document from Siemens. (the txt version from google which also includes my search terms for this whole post is here.) It talks about the advances being made to move towards medium voltage (1200V-13kV) DC transmission since the advantages of DC power transmission for high voltage systems are so well proven.

Now that that's out of the way: you've emailled me on more than one occasion asking about information on electronics and electricity in general and where to learn more. I find it mildly amusing that you jump up claiming to have enough knowledge to scream at the top of your lungs that what you know is 100% true and proven and that what I had suggested was totally and wholly false. I didn't reply to bitchslap you but I do wonder why you did try to do it to me?

[ Parent ]
Hmmm... (none / 0) (#53)
by Signal 11 on Sat May 12, 2001 at 07:23:57 PM EST

HVAC can't be rectified easily. I know of no easy way to do so at high voltage + currents. And I note that no transmission wires in my state, afaik, have DC going over them.

Society needs therapy. It's having
trouble accepting itself.
[ Parent ]

Easy is relative. (none / 0) (#54)
by tzanger on Sun May 13, 2001 at 12:39:28 AM EST

HVAC can't be rectified easily. I know of no easy way to do so at high voltage + currents. And I note that no transmission wires in my state, afaik, have DC going over them.

Actually the rectification of hundreds of thousands of volts is easy; I described one such method in the post you initially blew up on. Series-strung diodes do just fine. I actually think they use light-activated thyristors but I'm not 100% sure here. When you series them up you double their reverse voltage blocking capabilities but you also increase their forward drop. When you string devices in series you also require resistors to statically balance them and (in the case of medium voltage soft starting, which is part of what I do for a living) you also require dynamic sharing using snubber networks.

As I said, easy is relative. What I find harder is chopping the DC back into AC at those voltages and with decent efficiencies. It must be possible though, since those kinds of links are used in several situations, as was described in the first link of my previous post.

I don't have any charts but as I'm sure you're aware, ignorance doesn't necessarily mean something doesn't exist. I think you'd find DC lines at huge generation facilities as well as anywhere where you need to connect two non-synchronized grids. One of the links gives several different types of DC bus and what each is typically used for.

[ Parent ]
That's OK (none / 0) (#41)
by cei on Wed May 09, 2001 at 09:45:32 PM EST

Los Angeles generates its own power and is largely unaffected by the blackouts to the north.

[ Parent ]
Iceland - Scotland submarine power cable (5.00 / 1) (#12)
by Komodo321 on Tue May 08, 2001 at 01:37:03 PM EST

They've been talking about connecting Iceland to Scotland with a cable to make use of Iceland's surplus of geothermal and hydroelectric power. This talk has been going on as long as I can remember, but it has popped up again this week in this article in the publication Scotland On Sunday.

This is a case where even a 50% loss might be acceptable as long as the cable can pay for itself and provide economic power.

Make Aluminium (4.00 / 1) (#23)
by redelm on Tue May 08, 2001 at 04:32:02 PM EST

The best think Iceland could do with it's surplus hydropower is to smelt Aluminum. Aluminum takes so much electricity to make I call it solid electricity. Just import bauxite from Jamaica and export ingot to the EC or US.

Alcan already moves Jamaican bauxite into Jonquiere Quebec even though it's iced-in 4 months per year just because there's alot of hydro available there.

[ Parent ]

They already make aluminum (none / 0) (#39)
by Komodo321 on Wed May 09, 2001 at 02:13:26 PM EST

there are two aluminum plants there, one relatively new and big. Also, Ferro-silicon and cement manufacturing, which are also energy intensive.

[ Parent ]
Brazilian power grid (5.00 / 1) (#14)
by Pac on Tue May 08, 2001 at 02:05:23 PM EST

In Brazil we have power structure very similar to Canada (which can be seen in table 18-1, page 2, in the linked document), only our dependency on hydroelectrical plants is even higher, almost 90% if I remember it right.

Our largest generating plant, Itaipu, is located in the brazilian-paraguayan border, far away from the main consuming centers. In 2000 Itaipu produced some 93.428 GWh, being responsible for 24% of all brazillian power needs (and 95% of Paraguay power needs).

The two main transmission lines that bring Itaipu's energy to the souhteast region (where the largest brazilian cities, including São Paulo and Rio de Janeiro, are located) have 810 km (506 mi) and 910 km (~570 mi) runninig at 600kV and 750 kV respectively.

This map gives a good idea about the current state of power transmission grid in the south of Brazil.

Notice that the high hydro dependence rules out the possibility of NOT transmitting energy across great distances.

It was already determined that most energy problems Brazil is facing now are due to lack of investiment not in energy production, but in transmission lines that would allow for a better distribution of the energy. That is, while the southeastern states will have to save up to 20% of its energy expenditures during the coming winter (and probably face daily 3-hour blackouts for the duration), the southern region of Brazil have more than enough to cover for this need (if the transmission lines were in place).

All this to say that energy transmission over large distances can probably be made efficient, specially when you absolutely need it (since most rivers are not kind enough to flow near the places that need the energy). It is probably not the case in US, sice coal and nuclear plants are usually smaller and made to serve its extended neighbourhood

Also, transmission lines and processing and storage stations along the line have a limited capacity. If the lines and stations are already in use they may not be able to cope with the added traffic.

Evolution doesn't take prisoners

Sorry to hear about Brazil's power rationing (none / 0) (#45)
by turtleshadow on Thu May 10, 2001 at 12:46:40 AM EST

I'm hearing & reading about Brazil now planing on rationing its power due to low rainfall causing Hydropower to "dry-up."
I have just come back from Sao Paulo with my co-workers aka the sunburned Gringos.
If California is complaining how is your economy going to survive?


[ Parent ]
A few points of interest... (2.00 / 1) (#20)
by jd on Tue May 08, 2001 at 03:02:02 PM EST

First, power loss (resistance) is a function of voltage and current. V = I.R. (No, not the one on Cartoon Channel. :) If you increase the current, but keep the voltage the same, you must decrease the resistance.

In practice, what you usually end up doing is increasing both the voltage -and- the current, allowing you to deliver much more power at (proportionately) less cost.

This is one reason some European countries opted for a 13 amp, 250-volt system. The loss is much less, per unit of energy delivered.

The problem of California (and the US as a whole - don't imagine that this won't affect other States, over time) can therefore be easily resolved. Simply ramp up the power grid, thus delivering much more of the power that's actually generated.

The second part of the problem is how to reduce the resistance -in- the cables. Copper is being replaced with aluminium, which is a good place to start. Chip manufactuerers are going the other direction, to improve performance. The only benefit aluminium has is that it improves the quarterly figures, increasing the value of the shareholders' stocks.

Actually, the best metals to use would be silver and gold. Their conductivity is vastly superior to copper. Yes, silver is also very reactive and isn't exactly strong. That's why you'd probably want something like a silver glaze, with some sort of polish to prevent it oxidizing. (You don't need a lot of silver, as the current is carried on the surface, not in the core.)

If you wanted to switch to something a bit more exotic, there's no actual reason to deliver current that way at all. Make a -hollow- cable, and use it as a wave-guide. Blast electrons down it. This "simulates" the likely behaviour of super-conductors, without needing to produce ultra-cold temperatures.

The main problem with this solution is that it would require replacing a lot of cable, as it's not a trivial upgrade, in the same way the others are.

The bottom line, though, is that de-regulation, combined with inane, archaic and obsessive cheapness has created this crisis. Only when the energy companies and politicians are dragged, kicking and screaming, into the present day, EVEN IF THAT MEANS RAISING TAXES!, will any solution be even remotely considered. A medieval mind CANNOT fix problems that don't exist in a medieval world.

Raising taxes... (none / 0) (#28)
by ucblockhead on Tue May 08, 2001 at 05:45:26 PM EST

In California's case, raising taxes will do almost nothing. Hell, we're running a surplus these days. The state has extra cash. In fact, one of the plans Davis is trying to push through involves using tax dollars to buy PG+E's transmission lines from them. PG+E doesn't want to do that, though.

The irony is that this privitization scheme may end up forcing the state to take over some pieces of the power system!
This is k5. We're all tools - duxup
[ Parent ]

California power issues (5.00 / 3) (#30)
by sigwinch on Tue May 08, 2001 at 06:32:32 PM EST

Simply ramp up the power grid, thus delivering much more of the power that's actually generated.
You can't just increase the voltage by twisting a dial. The transformers don't work that way, and a much higher voltage would cause arcing.
That's why you'd probably want something like a silver glaze, with some sort of polish to prevent it oxidizing. (You don't need a lot of silver, as the current is carried on the surface, not in the core.)
"Skin" depth is proportional to frequency. You're right for radio frequencies, where the skin depth is a microscopic distance: RF antennas, waveguides, resonators, and so forth are frequently silver plated. Unfortunately, at the 50 or 60 Hz commonly used by utilities, the skin depth is a whopping several centimeters. You'd need a silver cladding several millimeters thick to even notice a difference, and that'd be expensive.
Make a -hollow- cable, and use it as a wave-guide.
RF waveguides are rather lossy and inefficient. Low frequency wave guides are unwieldy large (think kilometer scales).
Blast electrons down it. This "simulates" the likely behaviour of super-conductors, without needing to produce ultra-cold temperatures.
Electrons repel each other: a beam of electrons would tend to spread itself into the walls unless large axial magetic fields are used. Superconductors do their magic by a combination of two effects: 1) The positively-charged nuclei of the conductor form a space charge that effectively cancels out the bulk electron charge, so the electrons don't repel each other (much). 2) The quantum properties of the crystal lattice create a modest *attraction* between electrons, which in effect "glues" the electrons to each other. In normal conductors, you can scatter electrons one at a time, and it's easy for resistance to occur. With the "glued together" electrons in a superconductor, you have to simultaneously work against a large number of electrons in order to cause resistance. If you don't overcome the threshold by affecting enough electrons, there's no resistance; if you do overcome the threshold, superconductivity vanishes all at once. Creating a lattice where electrons can attract each other turns out to be difficult, and the finest minds in physics have had comparatively little success.

I don't want the world, I just want your half.
[ Parent ]

physics, physics, physics.... (5.00 / 2) (#38)
by krlynch on Wed May 09, 2001 at 02:07:43 PM EST

First, power loss (resistance) is a function of voltage and current....Simply ramp up the power grid, thus delivering much more of the power that's actually generated.

Actually, high voltage AC power transmission is a whole heck of a lot more complicated than just looking at resistance. You have to consider the full impedance calculation, including resistive, reactive (capacitance effects) and inductive loading. And you have to consider Lenz' Law (You can't just dump electrical power into a transmission systems suddenly; nor can you take it out suddenly. The network will "fight back"). And you have to consider the breakdown voltage of the air (you have to make user your transmission wires are far enough away from you towers, so the current doesn't arc through the air). You also just have to think about the effects of those larger voltages and currents on things like transformers, circuit breakers, fuses, switches, generators, and the stability of the system overall. It isn't just a matter of "ramping up the voltage", or "replacing a few cables", and it can't be done overnight. It would require a massive retooling of subsets of the network, or the construction of new transmission lines, substations, and generating plants. Exactly what California has refused to do over the last decade.

... the current is carried on the surface, not in the core.

Current is NOT just carried on the surface of a conductor. It IS a true statement that STATIC charges are held only on the surface of a conductor, but mobile charges (ie. currents) penetrate a conductor to varying depths, dependent on the material, cross sectional area, current, and conductor configuration.

Make a -hollow- cable, and use it as a wave-guide. Blast electrons down it.

This will not work at all. It is NOTHING like the operation of a superconductor. With this type of system, you'd be lucky to transmit electrons a few millimeters before beam self interactions and collisions with gas molecules would cause blooming and destruction of the beam. The classic solution to drive more power is to build larger towers supporting thicker cables held farther from the tower supports (and each other) and run the transmissions at high voltage with low currents.

All of this should be covered in any freshman physics E&M textbook.

As others have mentioned, the problem in California is neither a technological nor a business problem, but a psychological and political issue. You can't forbid the market from working its magic on the demand side, while simultaneously expecting the market to function on the supply side. It's never worked in the past, and it can't work in the present.

[ Parent ]

good background reading (none / 0) (#31)
by danny on Tue May 08, 2001 at 11:49:33 PM EST

If you're after some electrical engineering background, I recommend Theodore Wildi's Electrical Machines, Drives, and Power Systems. That's a relatively non-mathematical treatment of the subject.

[900 book reviews and other stuff]

An easier solution (5.00 / 1) (#32)
by mattc on Wed May 09, 2001 at 12:57:50 AM EST

Why not just get rid of the air conditioners? I never liked them anyway. A fan takes much less energy I'd think.

Rolling blackouts (none / 0) (#33)
by jynx on Wed May 09, 2001 at 06:40:09 AM EST

Having to take turns at having the power on. Whoever heard of such a thing? :) Next thing you'll have to get your water out of a well.

California is becoming a third-world country. :)


California=cardhouse of dreams built upon desert (none / 0) (#43)
by turtleshadow on Thu May 10, 2001 at 12:41:48 AM EST

I understand that in Disney's California (TM) there's a new ride called the rolling blackout express.

[ Parent ]
It is very realistic. (by someone in the field) (4.00 / 2) (#35)
by Peeteriz on Wed May 09, 2001 at 08:23:01 AM EST

I work in electric grid dispatching for the Baltic Rim (Estonia,Latvia,Lithuania,Kaliningrad).

What I have to say is:
1) It is entirely possible to economically efficiently transfer large amounts of power at large distances.

2) What I have learnt about power management in USA is that often, when calculating costs, planning generation at power systems, etc, power losses in system are not taken into account AT ALL. (They are non-trivial to compute, and their dependency upon a huge sum of factors, and different parts of system owned by different organisations would make it an economical mess)
The losses in high-voltage, longdistance networks make up less than 3-5% of total generation. (YMMV)

3) You cannot 'transmit' power through the grid.
You can pour more in at one place, and suck off more at another.
It changes the balance of voltages through entire grid, affects a (huge) number of other things. The losses of system do increase for a amount that can be calculated, and you will be billed that, if you make a power delivery contract or whatever it is called at USA.
But, the increase of total losses is many times (around 10-20 times, can't do the math now) LESS than it would be if you transmitted the power through a wire unconnected to the grid for the same distance.

4) My opinion about the California crisis :
Basically, f*** 'em. Start the blackouts.
Explanation Follows :
The only reason that there is an energy crisis in California is that the people, and local officials there have practised an unhealthy amount of NIMBY'ism. (Not in my backyard) And, because of the strict power regulation that was there, and right now is being removed, the consumers have been blissfully ignorant about the effect of NIMBY'ism on power prices.

They had scared many powerplant projects away, and simple economy encourages California's powerplants to sell power to other regions, because they get higher price there. And the Calif'ians, well, get screwed.
California, listen ! The way it would be is that you'll get 100-200% increase in electricity prices. THEN, maybe in 5-10 years you'll have a couple of large powerplant projects offered. And you will have a choice : either pay even more for electricity, as time goes, or allow either a huge Nuclear Plant, or a (heavily polluting) Thermal Plant right there in your backyard.
Some time ago the choice was to drop powerplants. Now you have the consequences of your actions. If not your actions, then the actions of Green protesters, whom you supported by being silent.

If anybody is interested about hard numbers for power transfer for points 1-3, or has hard numbers about Calif, email at
DISCLAIMER - the opinions are strictly mine, and not those of any organisation whom I may represent.

My opinion from someone who lives in California. (1.33 / 3) (#40)
by binford2k on Wed May 09, 2001 at 02:26:13 PM EST

4) My opinion about the California crisis : Basically, f*** 'em. Start the blackouts.

No, Fuck You.

Do you realize how much of the entire USA depends on California?

Do you realize how much it would cost you for a date if we quit making movies because our power got shut off?

Do you realize what your next computer would cost if Intel closed shop in CA?

  • The California computer manufacturing industry employs 254,300 people, composing 25 percent of the nation's total.

And we better keep our food too, if we don't have electricity to keep it fresh. Think about us when you go grocery shopping

"California is truly the breadbasket of the nation, and as our State's largest industry we must support its role in feeding the world. The variety of crops produced is enjoyed by billions of people around the globe." - Governor Gray Davis

California's agricultural industry feeds the world. Governor Gray Davis is committed to this community, one of the largest economies in the State.

Economic Aspects

  • For more than 50 consecutive years, California has been the number one food and agricultural producer in the United States. California's agricultural output is nearly $25 billion per year and produces over 350 different crops and commodities.
  • California grows more than half the nation's fruit, nuts, and vegetables.
  • California is the nation's number one dairy state. California's leading commodity is milk and cream. Grapes are second. California's leading export crop is almonds.

And how bout this? Hoping to start a business? Depend on industrial research? Sucks to be you.

  • Financial resources are second to none in California. Over 40 percent of all U.S. venture capital is sourced here. California also accounts for more than 20 percent of the nation's industrial research laboratories and receives one-fifth of federal research and development funds.
  • California is by far the largest exporting state in the nation, generating some $107 billion in export sales in 1999. It also tops the tourism and travel category, with $68 billion in sales in 1999.

Don't you people realize that if our power gets shut off, YOU are going to be hit too? Perhaps worse in some cases. Without electricity, we can't ship you milk. But you damn well better believe that we're gonna drink it!

So like I said. Fuck YOU

[ Parent ]

Guess what (4.50 / 2) (#46)
by physicsgod on Thu May 10, 2001 at 03:07:01 AM EST

Not one of the things you listed is unique to California. If things get too bad there other places will take up the slack, the Intel plant in Colorado Springs will expand, Florida will produce more produce, MIT, Harvard and Fermilab will get more grant money for research.

But I do have a solution: get thousands of stationary bikes, hook them up to generators and distribute them with the message "Pedal to generate electricity for the Californians, or they'll be coming HERE next." Should work here in Colorado. ;)

--- "Those not wearing body armor are hereby advised to keep their arguments on-topic" Schlock Mercenary
[ Parent ]
FEH! (none / 0) (#47)
by minusp on Thu May 10, 2001 at 09:15:31 AM EST

Go rot. If you were 0.0000000001% as important as you think you are, maybe I could change my mind.

I'd miss some of the adequate wines, though, for a while.

Remember, regime change begins at home.
[ Parent ]
read the damn reason (none / 0) (#50)
by IronDragon on Thu May 10, 2001 at 08:41:51 PM EST

As stated, the reason for your current power troubles is largely due to the 'feel good' environmentalism that the majority of californians subscribe too. People wanted to build power plants, Californians wouldnt let them. A power shortage is the logical result.

In your post you have stated that the rest of the USA depends upon California. Well woop-de-do. Thats nice, but we're not going to solve your damn energy problems.

I would like to see more power plants built. However, theres still many who would prefer to live in caves in order to 'make the land greener'. Find those idiots, as theyre one of the roots to this problem.


[ Parent ]
Cretièn and Bush? (none / 0) (#42)
by Prophet themusicgod1 on Thu May 10, 2001 at 12:37:07 AM EST

Apparantly there were talks to tap some of Canada's Electricity(which we have at least a small abundance of, enough for california at least) between Jean Cretièn and GWb...but i havnt heard where those talks got to yet. just a thought.
"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
Isn't California buying from Canada already? (none / 0) (#44)
by ridge on Thu May 10, 2001 at 12:45:24 AM EST

All the conversation so far makes this sound only hypothetical, and yet...


Loss rate (none / 0) (#55)
by cynwoody on Sun May 13, 2001 at 07:27:30 PM EST

losses of 0.0036%/km, or ~50% over 2000 km
According to my calculator, that loss rate would need 19254 km to lose half the juice. To lose half over only 2000 km, the loss rate would need to be about 0.0347%.

Is long-distance electric power transmission realistic? | 55 comments (53 topical, 2 editorial, 0 hidden)
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