Arizona Could be Persian Gulf of Solar Energy

[Chuck]

Power for 70,000 homes.

Amanda Lee Myres - AP - Feb. 22, 2008

Lots of sun available in the desert Southwest for solar - Ed

PHOENIX — A Spanish company is planning to take 3 square miles of desert southwest of Phoenix and build one of the largest solar power plants in the world.

Abengoa Solar, which has plants in Spain, northern Africa and other parts of the U.S., could begin construction as early as next year on the 280-megawatt plant in Gila Bend — a small town 50 miles southeast of Phoenix. The company said Thursday it could be producing solar energy by 2011.

Abengoa would build, own and operate the $1 billion plant, named the Solana Generating Station…[Read More]

[Indigo]

We *really* like the idea of clean energy for 70,000 homes. Once built, it should also take a huge load off the terrestrial (coal/gas/nuclear) power grid.

[southerncannuck]

It's a shame that it won't be an American company

[Vooch]

7% of germany's power now comes from wind & solar

[Bucko]

I sure hope it doesn't really take all of the 3 square miles to only produce 280 megawatts. Not sure what the average home consumes in the desert southwest but 4Kw per home seems a bit on the light side.

[rweatherford]

What else are they doing with those 3 square miles? Perhaps they can add some windmills too.

[Tochatihu]

Solar energy map:

http://www.thefarm.org/charities/i4at/surv/solmap.htm

Wind resources map:

http://www.eere.energy.gov/windandhy.../wind_maps.asp

There are a few places where the "two fer" works out pretty well. For reducing bird-chop, try to avoid the flyways:

http://www.birdnature.com/allflyways.html

Sort of a thread-hijacking, but I prefer a holistic view to these issues.

DAS

[pdk]

Originally Posted by Tochatihu

Solar energy map:

http://www.thefarm.org/charities/i4at/surv/solmap.htm

Wind resources map:

http://www.eere.energy.gov/windandhy.../wind_maps.asp

There are a few places where the "two fer" works out pretty well. For reducing bird-chop, try to avoid the flyways:

http://www.birdnature.com/allflyways.html

Sort of a thread-hijacking, but I prefer a holistic view to these issues.

Definitely not a hijack, as this is quite relevant, and hard data is quite appreciated.

So, feel-free to double-check my numbers on this, but let's look at energy per square mile from this map:

For Arizona (erring toward the conservative side of average) 6,500 Wh / sq m * 2,589,988 sq m / sq mi = 16,834,922,000 Wh / sq mi / day (sq meter to sq mile conversion provided by Google calculator).

16.8 Gigawatt hours per day from one square mile of solar collectors? I'm thinking I've done something wrong here in my numbers. I checked them at least 3 times.

While not all of that land will be used for just solar panels, and you'll certainly lose some energy in the conversion and transmission processes, you're probably still operating on the order of several GWh/day of actual usable energy if you can get a total of 1 square mile worth of solar panels from a number of sources. Holy s***.

Also, for sake of comparison and context, 1 gigawatt hour is 3.6 trillion joules (per Google calculator), and coal has an energy density of 24 megajoules per kilogram (per wikipedia). So it theoretically takes 150,000 kg of coal to produce 1 GWh of energy, which is ~330,000 lbs, or 165 tons.

Just for kicks, what would a home in Wisconsin generate (theoretically, keep in mind potential transmission and conversion losses)? I'm going to assume a "typical" semi-detached home, with a roof area of 72 sq m (http://www.resurgence.org/energy/heac/index.htm). I'll also assume that due to conversion and transmission losses, as well as the fact that a roof can't follow the sun and not all of the roof will be exposed, that you'll only get 50% of the theoretical maximum.

3,500 Wh / sq m (low side of average) * 72 sq m * .5 = 126,000 Wh / day = 126 KWh / day. That would help take quite a chunk out of my electric bill. Even at 1/3 total efficiency you're still talking about 84 KWh / day. Yikes.

[Tochatihu]

It is pretty fantastic the amount of solar energy that falls on a square mile of sunny desert. I'll take a stab at some downgrades thereof.

The watt hours map includes infrared that PV can't use. Maybe 50%
Typical PV panels are 13% (20% cost much more)
If you don't track the sun with them and just hang them at the latitude angle, 60%
Areal coverage (gotta leave some space I guess) 75%
Convert the DC to high voltage AC 80% (a real WAG)
Transmission efficiency 95%

Any of these could be revised up or down, but with all these efficiencies multiplied in series, I get 2.2%. If I am in the right ballpark, getting 2% of AZ sunshine out of the other end of a long wire should be doable. 3% might be pushing it.

PV panels seem to be $5/watt; $55/sq. ft. retail. Maybe if you buy a square mile of them you could get $2/watt Writing the $400 million check is the problem; after that, 1 GWh of electricity per year from your chunk of desert.

DAS

[Right Lane Cruiser]

Actually, wasn't the article about generating electricity from solar heat? That should help boost the efficiency quite a bit over what PV can accomplish.