subject: Solar Satellites Will Power Earth, Scientists Say
posted: Wed, 19 Jan 2005 22:17:31 -0000

Solar Satellites Will Power Earth, Scientists Say
By By Alex Canizares
Special to SPACE .com
posted: 02:29 pm ET
08 September 2000

WASHINGTON, Sept. 7 (States News Service) – Solar-powered satellites
will become a major energy source by 2030, scientists testified at a
congressional hearing Thursday, helping to reduce reliance on
dwindling fuel supplies.

With fuel supplies projected to fall and energy costs reaching
historic highs, using satellites to transmit energy to provide
electricity used to heat homes and run appliances is becoming
technologically viable, scientists told the House Science
subcommittee on space and aeronautics.

Electric energy use is projected to grow 75 percent worldwide by
2020, and oil production will slow due to depleting reserves after
2015, said Ralph H. Nansen, president of Solar Space Industries.

"Space solar power can solve these problems," Nansen said. "The time
is now right for their development to begin."

A roadmap

John C. Mankins, manager of Advanced Concepts Studies at NASA, said
the space agency is laying out a "roadmap" to develop satellite-
powered energy using several technologies in the works.

High-voltage solar panels that could handle sunlight during 99
percent of a 24-hour day, wireless transmitters that can beam large
amounts of microwave energy, and an "inflatable radiator" to absorb
heat in space, are all under development, Mankins said.

Relaying power from ground stations to satellites and back to ground
stations at another location is another, perhaps more readily
available, application, Mankins said. A complete solar power
satellite system to produce enough energy to be economically viable
may not emerge until 2025 to 2035, he said.

The idea of transmitting solar energy from space to earth first
emerged in the 1960s, but research efforts failed to gain ground
until 1995, when NASA and other scientists began studying the idea
more carefully using better technology. NASA spends $22 million
annually on the research.

The next step, Nansen said, is building a ground test program to
integrate various technologies, including 20 to 50 kilowatt solar
arrays, antennas to transmit energy, and distribution grids, that
would essentially transmit energy across a 1 to 5 kilometer range on
the ground.

However, the scientists said, the costs of launching satellites and
hardware into space represent a "significant challenge" to making
solar space energy viable.

Mankins said there is no evidence yet that energy transmission from
space using microwaves or lasers would damage the environment. In
fact, the use of solar-derived energy may benefit the environment by
reducing reliance on fossil fuels, he said.

Rep. Dana Rohrabacher, R-Calif., and the subcommittee chair, said he
supported looking for "new sources of energy that are clean" so that
energy costs are reduced and "so we won’t have blackouts in

Rohrabacher, who has introduced legislation aimed at reducing launch
costs, said space solar power is "one reason why I am a strong
advocate for cheap access to space."

* Origin: [adminz] tech, security, support (192:168/0.2)

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