World's Largest Solar Array to use Stirling Engine

An anonymous reader writes "Stirling engines are not a neglected or forgotten technology after all, according to a story at PESN. With 20 years of in-the-field fine-tuning, Stirling Energy Systems is now ready to go big -- real big. They signed a purchase agreement Tuesday with Southern California Edison (SEC), to install a 20,000 dish array that will cover 4,500 acres and will be capable of generating 500 megawatts of electricity -- more than all other U.S. solar projects combined -- making this the largest solar installation in the world. Each collector has a 37-foot-diameter array of mirrors to focus the sun's rays on the Stirling engine, which turns the heat into rotational torque for electricity generation. According to a spokesperson for SCE, this purchase will be in their commercial interest, requiring no subsidy in order to compete, implying that the efficiencies of the technology will give them an edge in the market."

Comments

Not surprising

[benjamindees]

I'm not surprised stirlings are finally profitable.

But those giant dishes look expensive and complicated.

Doesn't anybody have a way to make large parabolic reflectors cheaply? Or isn't there a way to do away with the tracking devices?

Re:Not surprising

[inode_buddha]

I've seen people take the old 6-foot TV dishes and mirrorize them, either with silver paint or glueing a zillion tiny glass mirors onto them. Mother Earth News did a project like that back in the 1970's IIRC. The heat near the focal point was in the thousands of degrees F and powered a small energy-efficient home.

Re:4500 acres?

[uberdave]

Counting or not counting the uranium mines, heavy water refineries, and spent fuel storage facilities?

Re:4500 acres?

[RandUser]

Touche. Which is why I think we should be focusing research and energy on nuclear fuel reuse [waaaay unexploited in the US] and disposal techniques.

OK, so what's the catch?

[Bryan Ischo]

I know some knowledgeable Slashdot reader can help me here. What I want to know is, what is the drawback to such a power system? It sounds like it generates quite a bit of power, and looks like a completely clean source. Are these things super expensive to build? Is it really hard to keep these things lined up with the sun to produce optimal power?

There is the issue of not being able to produce any power at night. But intelligent use of battery stores along with some supplemental traditional powered generators might take care of that, especially since power draw from the grid is (I'm guessing) much less at night.

So - what's the catch? Why aren't fields of these things going up like crazy?

Re:Colorado voter initiative

[fimbulvetr]

The voters here in Colorado were suckered into an initiative requiring the utility companies to get 15% of their power from renewable sources whether it made economic sense or not.

The spin you put on this makes it seem bad, however, relatively speaking our idea of efficient alternative energy is less efficient than coal mining and what have you. So, sure, it might not make economical sense compared to non-renewable energy, but that doesn't mean it's a bad thing!

Another reason this whole thing isn't that bad is because it forces companies (Xcel, etc.) to actually work on R&D for making their energy production more efficient - they now have a vested interest in it. If that were not the case, they'd just be burning the candle at both ends with oil/coal and worry about the future when the future came about. Xcel has been putting in a lot of wind generators in SW Minnesota, and they're not done. I love to see those generators every time I travel through there - it means something is actually getting done.

As for the voters in Colorado getting suckered in, well, I hear you, they're not the smartest...

A couple of good reasons...

[Goonie]

I can't find the reference, but part of the problem is that the US nuclear regulatory regime is designed around the assumption of monolithic, large light-water reactors. The idea of a modular system where you can add another reactor module quickly doesn't fit in with the approval process, removing one of the biggest advantages.

Secondly, US companies aren't developing PBMR designs; South African and Chinese ones are. Funnily enough, the subsidies for nuclear R&D and deployment currently floating around Washington are aimed at the American nuclear power industry, not its foriegn competitors.

Mind you, if Westinghouse's cost estimates on its new AP-1000 power plant design turn out to be it's going to be pretty competitively priced anyway. Pebble beds aren't the be-all and end-all. One concern is whether there'll be enough helium available to run them...