Microwave beams sending electricity from space to power our homes may sound like a concept straight out of a science fiction novel, but with a recent announcement from PG&E, we may actually see a solar powered space station in the near future. The system would consist of a series of solar powered satellites 22,000 miles above the Earth’s equator that would generate electricity, convert it into radio waves and then transmit to a base station on Earth. PG&E has entered into a contract with California-based SolarEn Corp. to supply 200 MW of power by 2016. If they succeed in making space solar power affordable, this new technology could be a huge contender in meeting the world’s energy needs.
Space Solar Power is certainly not a new idea – in fact, it’s been around since the late 1960’s when Dr. Peter Glaser introduced the concept of a solar power system in high geosynchronous orbit. Solar power in space has clear advantages over Earth-based solar systems – namely it is 8 to 10 times more efficient. With no atmosphere to transmit through, no interference, and 24 hours of sunlight a day, space solar panels can act as a baseload power source instead of an intermittent one. That alone is an intriguing idea, although its execution will surely prove to be difficult. As an additional bonus, real estate in space is basically still free and there’s a lot of it. Of course that delves into the whole other topic of whether it is right to develop space at all without clear rules and regulations.
SolarEn Corp will use existing technology to launch the satellites into a geosynchronous orbit 22,000 miles above the Earth’s equator. When deployed, the solar station, which could be miles across, will begin to collect the sun’s rays and convert them into electricity, and then convert them into radio waves. Those waves will be beamed back to Earth to a receiving station, which is currently planned for construction outside of Fresno, CA.
Radiation from the radio waves is certainly a concern, but proponents of SSP say that if spread out over a wide area, the waves will not cause any harm to plant life, animals or humans. The receiving station therefor must cover a large area of land in a sparsely populated region, but still have convenient access to transmission lines.
The project is expected to cost around $2 billion, which will mainly go towards the R&D of the base station and launching the satellites. SolarEn CEO Gary Spirnak has complete confidence in the concept and the company’s ability to develop this system. In fact, he projects that they will be able to generate 1.2 to 4.8 gigawatts of power at a price that is comparable to other forms of renewable energy. PG&E is also committed to the idea and has entered into a 15 year contract with SolarEn to produce enough power for 250,000 homes.
This isn’t the only SSP under development now – Japanese Aerospace Exploration Agency (JAXA) is also workign on a similar system, but instead of radio waves, they will transmit power via laser beam. Both companies ideas seem a little far-fetched, but if either of them succeed, it could mean huge things for renewable energy generation.
Check out an interesting interview with Solaren CEO Gary Spirnak.