Solar energy could be coming from space satellites in the near future.
The investor-owned utility company Pacific Gas & Electric is seeking approval from state regulators for a power purchase agreement with Southern California company Solaren.
Solaren has contracted to deliver 200 megawatts of clean, renewable power over a 15-year period through satellite solar panels hovering in earth’s orbit and transmitted to Fresno via radio frequency by 2016, according to PG&E’s blog the “Next100.“
Cal Boerman of Solaren says they will be placing satellites in earth orbit that work together to harness solar energy in space and transmit it to earth. The satellites will be launched on a rocket just as any other satellite.
Representatives say PG&E has been looking for test bed projects to demonstrate new technological advancements in energy.
“Companies have been approaching us because they know we need to look for renewable sources of energy,” PG&E spokesperson Jonathan Marshall said. “We’re also looking into wave energy power because Northern California has a great coastline.“
Experts say the potential benefit of solar panels in orbit above the earth’s atmosphere is that they could be in full sunlight 24/7. This would improve on a major shortcoming of solar panels on Earth, where day, night, seasons and atmospheric losses make the resource intermittent.
Some have questioned Solaren’s ability to institute their plans. There’s also the issue of cost, which Boerman said will be a few billion dollars.
“While a system of this scale and exact configuration has not been built, the underlying technology is very mature and is based on communications satellite technology,” said Solaren’s chief executive officer Gary Spirnak in a Q&A posted by PG&E on “Next100.“
Solaren’s system would be “competitive both in terms of performance and cost with other sources of baseload power generation.“
Boerman says the costs will be in line with and comparable to ground solar, wind and other clean renewable energy sources. The project is being independently funded by Solaren. The state only needs to approve the contract between PG&E and Solaren.
Experts also say solar cells in space might produce several times as much energy over its lifetime compared to a similar solar cell located on the ground.
Although some see satellite solar energy as a great new renewable energy source, others believe there should be more of a focus on other sources.
“The low hanging fruit of renewable energy is wind power,” said UC Davis professor Adam Moule, who studies polymer solar cells, in an e-mail interview. “When wind is exhausted, geothermal, terrestrial solar and biomass are all more cost effective and more energy efficient. This is where money should be spent.“
There are unique concerns with this technology due to the possibility of power being lost over long distance transmission.
“Usually power is transmitted through wires,” Moule said. “Some power is lost over long distances due to resistive loss. This loss would not exist in radio waves, however; radio waves are difficult to direct and difficult to collect with high efficiency. Also there are large losses associated in converting solar power in DC to radio waves in AC and then to electricity at 60 Hz.“
Moule also said doing maintenance on the system is a lot tougher in space than on the ground.
The plans have elicited mixed feelings among others as well.
“While this is an interesting idea, there are many cost effective options for using solar power on earth that are available now,” said UC Davis environmental science and policy professor Joan Ogden.
“Next100“ says there is also no risk to PG&E customers, as PG&E has contracted only to pay for power that Solaren delivers.
The question of the solar space power’s safety was addressed in a February paper by NASA researcher James Logan on spaceenergy.com. Logan said that based on present knowledge, it is safe, provided current exposure standards are satisfied.
PG&E is required by the state to source 20 percent of their power from renewable sources by 2010 and 30 percent by 2017. They are producing the required amount so far.
ANGELA SWARTZ can be reached firstname.lastname@example.org.