Stirling Energy Systems (SES) mirrors to power CA's 500MW and 300MW Solar

Electrical Power Plants.

http://www.newscientist.com/channel/mech-tech/mg18825276.300

Myriad mirrors turn desert into energy farm
New Scientist UK - Nov 23, 2005

Myriad mirrors turn desert into energy farm
26 November 2005

GIANT mirrors will blanket thousands of hectares of desert in California as part of the two largest solar farms in the world.

The farms will use 11-metre-wide dishes coated with an array of glass mirrors. Made by Stirling Energy Systems (SES) in Phoenix, Arizona, each dish will focus the sun's rays onto a 750-kilogram engine containing metal piston cylinders filled with hydrogen.

As the gas heats to 720 °C, it expands, driving the piston before flowing out as the piston drops down and cool gas flows in. This drives a generator, converting solar energy to electricity at around 30 per cent efficiency.

The farms are due to join the grid by 2009. A 20,000- dish array in the desert near Los Angeles will produce 500 megawatts, while a smaller array near San Diego will generate 300 Mw.

From issue 2527 of New Scientist magazine, 26 November 2005, page 25

You'd think there'd be some alternative that's easier to contain and less, well, explosive.

Gotta be a mistake in reporting. These are Stirling (heat) engines, they can use any gas as the working fluid, including air.

http://www.stirlingenergy.com/faq.asp?Type=solar

Presumably it has very good expansion properties, although focusing the sun onto a famously flammable gas seems intuitively wrong... :nuke:

The hydrogen is not burned, a small amount is contained within the stirling engine.

Thermal solar is truly an underutilized technology that has been around for decades. On a residential level, solar hot water is a great entry level way every homeowner can get started using 'green' energy at a very low cost, and even for a do-it-yourselfer. http://solarroofs.com/

Thermal solar energy could also be used to power a train using well developed technology available now!

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x35508#35648

or search for 'solar train'...:woohoo: :applause:

It also led me to another article on a topic which interests me (fireless accumulator engine)...and the New Athena Project seems deserving of wider notice.

because it's the lightest molecule there is. Helium is much safer, and also leaks 40% more slowly.

Instaneous power is not energy.

A 1 kg mass dropped from a height of one meter disperses 500 Megawatts of instantaneous power if it comes to rest in two one hundred thousandths of a second. This is not quite the same thing as saying that we could power Southern California with one kg weights.

I actually like these mirror concentrators, and I think they work pretty well. Some commercial plants, although they involved bankruptcy for the builders, continue to operate profitably under new ownership.

The fact remains, though, that power is still not energy. These things are marginal contributors, but as peak load systems that operate best on hot days, they do displace some dangerous natural gas systems that otherwise would run air conditioners, and that, I suppose is a good thing.

...there are alternatives to fission, you know... ;)

The Stirling genset can use virtually any source of external combustion heat, not just concentrated solar energy. This system was trialled at the landfill of the Pima Maricopa Indian Reservation near Tempe Az. a few years ago, and relied on landfill gas and/or natural gas at nighttime and on cloudy days.