Post #2,685
7/24/01 9:31:59 AM
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California Energy Crisis
Initial efforts at conservation and a cool July have resulted in a severe power surplus, forcing the State to sell power at a loss, as low as $37/megawatt hour. Recent purchases were at $118/megawatt hour. Los Angeles Times, today.
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Post #2,704
7/24/01 10:37:37 AM
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Basic supply and demand
when something is scarce it costs more, when there's a surplus it costs less.
What I have to wonder, based on the [link|http://www.latimes.com/business/local/power/la-000060442jul24.story?coll=la%2Dheadlines%2Dbusiness%2Dpower|article], is why the state government sold power at a loss approaching $14 million in the first 16 days of July? You'd think after the first day or so they'd realize they didn't need to produce as much.
Was the weather forecasted for much warmer weather than experienced? Are the consumers conserving more because the higher prices are finally reflected on their bills? Which works better - "please conserve" or "your price is now higher"? This article, [link|http://www.latimes.com/business/local/power/la-000057726jul14.story?coll=la%2Dheadlines%2Dbusiness%2Dpower|High Power Prices Lit Fire Under Conservation], certainly indicates the later, and theorizes that if consumer prices had reflected actual costs, the blackouts would never have occurred or been much less severe.
Darrell Spice, Jr.
[link|http://home.houston.rr.com/spiceware/|SpiceWare] - We don't do Windows, it's too much of a chore
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Post #2,728
7/24/01 1:03:39 PM
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But, does the state control the production? -msg
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Post #2,733
7/24/01 1:10:42 PM
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Re: Basic supply and demand
You'd think after the first day or so they'd realize they didn't need to produce as much.
There are a couple of reasons for this.
First, power generation stations cost money to fire up and money to shut down. Thus it can be worth while to leave a plant online even if it's running at a lose if you expect prices to go up.
Second, power generation stations take time to start up and shut down. It can take a day or more to get some types running if they are fully shut down. So some plants are left running at low power so they can step up in case of a sudden surge in demand.
Third, some power generators have contracts that guarantee certain prices and rates of consumption. That is, some power generators have contracts that state that CA will buy between x1 and x2 megawatts of power at some fixed price. Basically the state here is saying that in exchange for a fixed good price, will promise to buy at least a certain amount of power.
Fourth, not all purchases are made on the spot market. Much of what CA is selling off on the spot market is power they probably agreed to buy earlier this year. They agreed on a price back then and they are stuck with it. Since they don't need the power and power doesn't store well, they sell it off on the spot market at whatever rate they can get.
If somebody could find a good way to store large amounts of power they could make a fortune by buying when prices are low and selling when prices are high. I wonder if you could setup an artificial lake halfway up a mountain near a river? Pump water up when it's cheap and let it fall through a generator when it's expensive. Evaporation would be your biggest foe, other then that water power is cheap to setup and maintain.
Jay
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Post #2,743
7/24/01 1:47:26 PM
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We already have several of those.
The Metropolitan Water District just opened a new one with an absolutely huge reservoir (though not the largest reservoir they have). It's now over half full, but they slowed down the pumping during the recent crisis so others could use the power. Now they're probably buying some of that cheap power the state is selling and running the pumps on it. It'll have a pretty good generating capacity when full.
When the MWD was excavating for the dams, they had a lot of archeaoligists and paleontologists on site, and unearthed several Indian sites and found a whole slew of totally complete mastadon skeletons, plus some mammoth skeletons (mammoths were not previously known to be this far south).
There are also a bunch of smaller pump/generator sites, some of which reverse daily with the power peaks and valleys.
We are also ramping up power generation from landfills, with a whole slew of microturbines running off the methane from rotting garbage. Later perhaps we'll mine the suckers since the largest volume is wood and paper, but right now it's cheaper to bury it (besides, landfills fight global warming by taking all that carbon out of circulation).
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Post #2,749
7/24/01 2:47:09 PM
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I suspect the contracts
the state signed are probably the bigger part of the picture. The "selling at a loss" will probably come back to haunt Davis during the elections.
I thought that power output of plants was more variable than "all, standby, or nothing"?
I've read about storing excess power by pressurizing natural gas in salt domes. Found this [link|http://www.geology.wisc.edu/geo411/case1.htm|case study] on it, don't know if it's implemented anywhere or not.
Darrell Spice, Jr.
[link|http://home.houston.rr.com/spiceware/|SpiceWare] - We don't do Windows, it's too much of a chore
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Post #2,753
7/24/01 3:17:06 PM
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It's being built
There's one in [link|http://www.beyond2000.com/news/Apr_01/story_1119.html|Ohio] that's under construction. It's a limestone mine instead of salt. They expect to pressurize during the day and recover at night to smooth the demand curves.
This is my sig. There are many like it, but this one is mine.
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Post #2,824
7/25/01 9:20:02 PM
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Depends on the powerplant
I thought that power output of plants was more variable than "all, standby, or nothing"?
Depends on the type of power plant. Power plants that burn things generally have to maintain a certain temperature/pressure to operate.
For example (pulling numbers out of the air), a 1000 MW/h plant might have to burn the same amount of gas for any production level between 1 and 250 MW/h because they have to reach a certain temperature before they can run the turbines.
The reality is much more complex, because large power plants have multiple units, sometimes in different sizes. But the general idea is still there.
Jay
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Post #2,847
7/26/01 12:30:18 AM
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Nope, just takes a bit of energy to operate turbines
although you can lose efficiency.
I believe nuke plants can run at various power levels with roughly the same efficiency. Of course, my nuclear power experience was in submarines; we did a lot of load cycling (changing power levels all the time) and didn't worry too much about efficiency, other than the fact that we wanted the core to last the life of the sub.
Again, steam-based power (e.g. fuel oil or coal) can run pretty well at lower power levels -- again I do have some naval experience with fuel oil systems (1200 psi superheated steam frigate) and IIRC efficiency at different powers isn't a big concern.
However, while gas turbines can run at low power levels, they aren't very efficient. Gas turbines have incredible power to weight ratios, are moderate polluters, and are reasonably efficient when at high power. Many of the new power plants, including in California, are natural gas-powered turbines. These plants would be more binary -- you'd probably want to run each turbine at pretty much capacity or not at all. And, of course, it was natural gas pricing that went soaring, thus directly affecting the price of natural gas produced electricity.
Tony
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Post #2,853
7/26/01 2:47:42 AM
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Perzackly.. well
approximately then - the big smoke screen, 'least in CA meeja, was the electricity rates, brokers yada yada.
Omitted: CA's major boondoggle (if I heard the various versions ~ correctly) of - deciding not-to fund a rather inexpensive connection link to existing Texas gas lines, some moons ago. However correct that version - the journyalists were bitchin about moderate e- rates and missing gas prices of over $1.40/therm! This in the midst of all the hand wringing. (A mobile home heating bill in the cold snap was near $400; mostly gas - I saw it)
Point being - none of these observers connected the gas costs commercially, too - as re the turbines!
Echoes the quality of press coverage of M/sloth I suppose. (Maybe it ain't all the journyalists fault.. as the newspaper monopoly becomes ~6 national players all owned by: _____ whatever you call wannabe monopolists almost there).
What readst thou, Hamlet?
Words.. words..
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Post #2,735
7/24/01 1:19:42 PM
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From what I've read
They bought power futures contracts back in the spring when they expected heavy power usage. California weather has been pretty gentle this year, so now they have power they've purchased and no one consuming it. Thus they need to sell it to someone.
French Zombies are zapping me with lasers!
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