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PG&E Makes Deal For Solar Power From Space

N!NJA writes "California's biggest energy utility announced a deal Monday to purchase 200 megawatts of electricity from a startup company that plans to beam the power down to Earth from outer space, beginning in 2016. Solaren would generate the power using solar panels in Earth orbit and convert it to radio-frequency transmissions that would be beamed down to a receiving station in Fresno, PG&E said. From there, the energy would be converted into electricity and fed into PG&E's power grid."

2 of 392 comments (clear)

  1. Re:makes no sense by Doc+Ruby · · Score: 4, Interesting

    Buying desert land isn't "astronomically expensive". It's about the cheapest land there is. There happens to be huge deserts of dirt-cheap (cheaper: sand-cheap) land all around California. Besides, this 2MW satellite probably doesn't even need more than about 25m^2 to receive its beam at 5x solar density. If they wanted to be really safe, they probably could diffuse it over 2500m^2, for 5W:m^2, which doesn't hurt anyone.

    The efficiency here is the 30% extra incoming solar power that is otherwise lost in the atmosphere (minus some small lost amount they're tuning the beam to minimize), times the 24/7 uptime instead of about 25% terrestrial due to night/weather/seasons. That's a starting point of 520%. But the other advantage is the much larger area that thin collector sheets can cover in space. Launching costs money per mass, but the collectors can unfurl across kilometers. And the maintenance costs in microgravity/femtopressure are much lower over years, despite the remoteness. After the large initial costs, the ongoing costs per watt are extremely low.

    2MW would require only about 40x40m collectors. A square kilometer collector would bring 1.3GW. The geosync satellite beaming to Fresno could receive from collectors in all kinds of other orbits pointing at the hub. This infrastructure could conceivably bring all 17TW of Earth's energy consumption into a series of ground stations from only about 114*114 Km of collectors. A few score hubs around the equator each using a few dozen GW lasers could replace all the coal currently burned for stationary power. The sky is literally the limit.

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    make install -not war

  2. Re:Bad idea by Hojima · · Score: 5, Interesting

    Everyone does that every day. It's called the sun. That's where this thing gets its energy from. However, there is a key difference between solar radiation, and the radiation that this machine produces. The reason that we have solar frequencies converted to this frequency, is because it interacts close to nothing with the atmosphere, or just about any organic particle/interference. A lot of matter interacts with very specific frequencies, which is why this frequency will only give power to the designated material. Think of an atom as a football at the center of the stadium. The electrons would be like flies in the bleachers. Now if you want to hit the flies with bullets, you have to aim to where they generally are, or you'll miss. It works kinda like that.