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Largest US Power Storing Solar Array Goes Live
Lucas123 writes "A solar power array that covers three square miles with 3,200 mirrored parabolic collectors went live this week, creating enough energy to power 70,000 homes in Arizona. The Solana Solar Power Plant, located 70 miles southwest of Phoenix, was built at a cost of $2 billion, and financed in large part by a U.S. Department of Energy loan guarantee. The array is the world's largest parabolic trough plant, meaning it uses parabolic shaped mirrors mounted on moving structures that track the sun and concentrate its heat. A first: a thermal energy storage system at the plant can provide electricity for six hours without the concurrent use of the solar field. Because it can store electricity, the plant can continue to provide power during the night and inclement weather."
The plant doesn't really store electricity. It can however, store heated salts that can be used to generate electricity well after sunset.
So I'm not going to respond to the first post because it makes no sense. But I'll happily use the "first reply" spot, thank you very much, to actually say something. This $2 billion plant breaks down to close to $30,000 per home serviced. Seems a wee bit excessive, considering the average home electric bill in Arizona runs something like $200 (I researched the web for a few minutes to estimate this). Consider that installing a home solar system would run something like $10-$20k at most in a sunny place like Arizona (considerably less w various tax incentives). Looking like a bit of a boondoggle?
Economics. You don't need nearly as much power between midnight and 6 (7? 8?), during which time the nukes and coal, which can't be throttled too much, will oblige. Designing heat storage capacity for around-the-clock is wasting money, at least in the current grid configuration and state of the tech.
Technically nothing stores electricity except for super-cooled superconductors. Batteries "store electricity" in the form of chemical energy and even capacitors only "store electricity" as two charged plates. But I think we all know what they meant, that it was storing the potential for electricity.
Well after sunset?
Actually, when you read up on it, the storage capacity is exhausted shortly after sunset. 6 Hours max.
The efficiency falls off at low sun angles.
Sunset usually happens right at peak demand time, evening cooking, and late afternoon air conditioning.
Plus the site has high ground to the immediate west, sunset comes earlier for them.
Don't get me wrong, this is an impressive feat of engineering.
It was installed very fast, hacked out of prime farm land (or as prime as it gets in Arizona).
Google Maps Satellite view, with imagery dated 2013 http://goo.gl/maps/Qh7e5 shows nothing
but desert with truck roads laid out, and now they are up and running.
(Either that or Google is Playing Fast and Loose with image dates, because Google Earth shows the same
images but has a 2010 date on them)
Sig Battery depleted. Reverting to safe mode.
Helps to read this in the voice of Sheldon.
Unfortunately, the link you posted doesn't mention the timescale for energy generation. I am under the impression that, like nearly all solar energy technology, that the primary cost is up-front installation, and maintenance costs are virtually zero thereafter. Using this assumption, we have
price / kWh = 2 (billion $) / (280 MW * t)
This gives t = (2 billion hours) / (280e3 * [100 * price in cents/kWh]) as the amount of time it would take to break even, or with some simplification, 81.485 years / P where P is the price in cents / kWh at which you wish to sell.
So if you were to sell at $.07 / kWh, it would ideally take 11.64 years to recoup investment (not taking into account additional costs and possible fluctuation in energy output). At double that price, it will take half the time. Either way, after that, I would say it's free energy. I don't see why there aren't more projects like this.
I have left slashdot and am now on Soylent News. FUCK YOU DICE.