SCIENTISTS are working on a revolutionary plan to supply the world's energy needs by building solar power stations in space.
Orbiting power plants capable of collecting solar energy and beaming it to Earth will be "technically feasible" within a decade, according to the International Academy of Astronautics.
Researchers believe the sun's abundant energy, if harvested in space, will provide a cost-effective way to meet the entire global power needs in as little as 30 years, with "essentially zero" terrestrial environmental impact.
"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," said John Mankins, the former head of concepts at NASA, who led the study.
The study did not estimate a potential overall price tag of building giant solar panels in space.
Details of the report will be officially unveiled at a news conference in Washington today.
The idea is to put first one, then a few, and later scores of solar-powered satellites, each several miles wide, in orbit over the equator.
The satellites 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 in space and sent to wherever it is needed on Earth by a large microwave-transmitting antenna or by lasers, then fed into a power grid.
Sceptics deem the concept a non-starter -- 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 three-year study found that the commercial case had substantially improved during the past decade, partly as a result of government incentives for non-polluting "green" energy systems.
A pilot project to demonstrate the technology -- even one as big as the 400-tonne International Space Station -- could go ahead using low-cost expendable launch vehicles being developed for other space markets, Mr Mankins revealed yesterday.
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 organisations in concert, including space agencies, companies, universities and non-governmental organisations.
International interest in the concept has grown during the past decade, spurred in part by fears that in coming decades global production of oil and other fossil fuels will peak and start to decline.
Adding to a quest for new energy sources are projected jumps in worldwide per capita demand for energy to fuel economic development and concern over the accumulation in the Earth's atmosphere of fossil fuel-derived greenhouse gases.
Jeff Peacock, who heads satellite-builder Boeing's ground-based solar cell product line, said this could double the amount of solar power collected, compared with the Earth-bound technology equivalent.