Orbital solar power plants touted for energy needs

WASHINGTON, (Reuters) – The sun’s abundant energy,  if harvested in space, could provide a cost-effective way to  meet global power needs in as little as 30 years with seed  money from governments, according to a study by an  international scientific group.

Orbiting power plants capable of collecting solar energy  and beaming it to Earth appear “technically feasible” within a  decade or two based on technologies now in the laboratory, a  study group of the Paris-headquartered International Academy of  Astronautics said.

Such a project may be able to achieve economic viability in  30 years or less, it said, without laying out a road map or  proposing a specific architecture.

“It is clear that solar power delivered from space could  play a tremendously important role in meeting the global need  for energy during the 21st century,” according to the study led  by John Mankins, a 25-year NASA veteran and the U.S. space  agency’s former head of concepts.

The academy is headed by Madhavan Nair, former chairman of  the Indian Space Research Organiza-tion. The study was billed as  the first broadly based international assessment of potential  paths to collecting solar energy in space and delivering it to  markets on Earth via wireless power transmission.

The study said government pump-priming likely would be  needed to get the concept, known as space solar power, to  market. Private-sector funding is unlikely to proceed alone  because of the “economic uncertainties” of the development and  demonstration phases and the time lags, the study said.

Both governments and the private sector should fund  research to pin down the economic viability of the concept, the  study said, amid concerns about humankind’s continuing reliance  on finite fossil fuels that contribute to global pollution.

The study did not estimate a potential overall price tag  for completing the project.

The idea is to put first one, then a few, and later scores  of solar-powered satellites in geosynchronous orbit over the  equator. Each as wide as several kilometers across (one  kilometer equals 0.6 miles), the spacecraft would collect  sunlight up to 24 hours a day, compared with half that, at  most, for surface panels now used to turn sunlight into  electricity.

The power would be converted to electricity on-board and  sent to wherever it is needed on Earth by a large microwave-transmitting antenna or by lasers, then fed into a  power grid.

Skeptics deem the concept a nonstarter, at least until the  cost of putting a commercial power plant into orbit drops by a  factor of 10 or more. Other hurdles include space debris, a  lack of focused market studies and high development costs.

The study, conducted from 2008 to 2010 then subjected to  peer review, found that the commercial case had substantially  improved during the past decade, partly as a result of  government incentives for nonpolluting “green” energy systems.

A pilot project to demonstrate the technology even as big  as the 400-tonne International Space Station could go ahead  using low-cost expendable launch vehicles being developed for  other space markets, Mankins said in a telephone interview. A moderate-scale demonstration would cost tens of billions  of dollars less than previously projected as a result of not  needing costly, reusable launch vehicles early on, said  Mankins, president of Artemis Inno-vation Management Solutions  LLC, a California consultancy.
“This was a really important finding,” Mankins said,  referring to a relatively modestly priced pilot project.

‘IT’S A START’      

His company has been awarded a NASA contract of a little  less than $100,000 to pursue space-based solar power options —  small “but at least it’s a start,” Mankins said.

Ultimately, tens of billions of dollars would be needed to  develop and deploy a sufficiently low-cost fleet of reusable,  earth-to-orbit vehicles to launch full-scale commercial solar  power satellites, the study group estimated.

The group said the necessary research and development work  should be undertaken by countries and organizations in concert,  including space agencies, companies, universities and nongovernmental organizations.