Humanity faces a new energy crisis. A growing population and rising per-capita energy consumption require a move away from the polluting, finite energy supplies now in use. Moreover, renewable energy sources such as conventional solar and wind power can only meet a portion of projected needs.

Space holds the key to an inexhaustible, non-polluting energy supply. That key is space solar power (SSP) -- using space-based systems to collect the sun's energy and turn it into usable power for Earth.

SSP would employ satellites in Earth orbit or systems on the moon's surface equipped with solar cells that convert the sun's energy into electricity. The electricity is fed to transmitting antennas and beamed to receiving antennas on Earth, located on land or offshore.

This is not some futuristic dream. The key SSP technologies -- solar cells and wireless power transmission (WPT) -- are based on the work of 19th century innovators such as Henri Becquerel and Nikola Tesla.

The conversion of solar energy in space to usable power on Earth is the most plausible global alternative to nuclear power plants.
     

During the past three decades, SSP has been studied extensively by space agencies, universities and industry groups worldwide. International meetings have been held on the subject since 1970. There now exists a large and growing literature on the technical, economic and societal issues associated with SSP.

NASA and the Energy Department conducted a joint-evaluation program of solar power satellites in the 1970s, but interest among policymakers declined after that decade's energy crisis faded away. Recently, U.S. political interest in SSP has begun to revive -- sparked in part by the specter of global warming -- though other nations, including Japan and Russia, have conducted serious SSP research throughout.

But much greater attention and effort are needed. SSP should become a top priority of the U.S. space program, and more broadly of government and industry in the U.S. and around the world.

Consider the energy situation now confronting the world. Industrialization and urbanization will mean sharply increased energy use. Reliance on fossil fuels could produce unprecedented environmental damage. Moreover, such finite sources may soon be past their peak availability, if they aren't already.

The solution to this problem is to utilize terrestrial renewable energy resources to the maximum extent possible, while at the same time developing SSP as a global, 24-hour-a-day energy supply.

The conversion of solar energy in space to usable power on Earth is the most plausible global alternative to nuclear power plants, with their attendant safety, decommissioning and plutonium proliferation issues.

SSP can also be an integral part of global development. It can help boost economic growth and improve living standards. It is the only means toward increased energy supplies compatible with the environment.

Space solar power is a challenging, long-term opportunity to tap space's unlimited resources rather than relying only on Earth's limited ones. It will help sustain human life on Earth and, at a future time, in space.