Among the many innovative technologies we'll see in the near future, here are a couple of innovative uses for solar coming down the pike: solar energy beamed down from space and solar used to recycled carbon dioxide into fuel.
These and hundreds of other technologies we can barely imagine today offer solutions to our climate change challenge - if we can cross the threshold and put a price on carbon through US legislation and if countries take a stand and commit to moving forward to a prosperous, green economy at Copenhagen. Solar from Space?
Yes, the first contract for beaming solar energy from space has been approved.
As part of its effort to obtain 33% of electricity from renewable energy sources by 2020, the California Public Utilities Commission (CPUC) approved the contract. California utility PG&E will receive solar energy generated by Solaren Corp's orbiting satellites through a long term power purchase agreement. Solaren says it can provide 1700 GW-hours of energy a year for the 15-year contract, which starts in 2016.
Once the 200 MW solar plant is hoisted into space (no mean feat) it has the advantage of 24-hour a day sunlight. No clouds to worry about. The day/ night cycle of the earth is irrelevant. Solar cells in space would capture about five times more energy as that on earth. It would also be possible to beam solar anywhere in the world, especially useful for regions that lack sunlight - and getting permits to build on sensitive lands isn't a problem.
Can Solaren do it? The founders are veterans of Hughes Aircraft, Boeing and Lockheed so it has a shot. Although the price tag will be several billions of dollars more than for a similar sized earth-based solar plant, Solaren believes they can bring costs down by light-weighting the system. PG&E didn't disclose the price of the power purchase agreement.
Here's how it works: a Mylar mirror, about a kilometer in diameter, would be inflated and float freely once it reach its orbit. From there, sunlight would be concentrated onto smaller mirrors, which would focus the light on PV modules. The resulting electricity will be converted into radio frequency energy that's transmitted to a receiver station on the ground. After the radio waves are converted back into electricity, it's fed into the grid.
The company plans to start launching components into space for testing in 2012. The construction of the plant will be subcontracted to the aerospace industry. It's not a big risk for PG&E because they only pay when they receive electricity.
Japan's Aerospace Exploration Agency (JAXA) is also working on a solar power space station - by 2030. Research has been underway for 10 years - the plan is to put a 1 GW solar unit into orbit that generates electricity for about 8¢ per kilowatt hour. Rather than siting the receiver on land, the energy would be transmitted to floating "lily pads" in reservoirs or in the ocean via microwaves. One satellite is set to launch around 2013, which would evaluate the microwave transmission device and any negative impacts on the environment.
