The National Security Space Office (a division of the Pentagon) released a report recently looking at the feasibility of building a massive solar array in Earth's orbit, that could beam power to the planet. The primary motivation for this research seems to be the general uneasiness military commanders have with relying solely on fossil fuels for the power and fuel requirements.
"Preventing resource conflicts in the face of increasing global populations and demands in the 21st century is a high priority for the Department of Defense. All solution options to these challenges should be explored, including opportunities from space," the publicly released report begins.
The feasibility analysis suggests building a giant space-based solar collector may be a good way to deliver power to the Earth. Echoing ideas put forth in science fiction (first by Asimov over 50 years ago), the solar array is now a much better looking proposition as new solar power technology has raised efficiency of solar cells to around the %40 mark (%40 of the solar energy striking recent photovoltaic cells can be converted to usable energy). The energy potential is huge, as this following graphic shows, in one year's worth of orbit, an array of the magnitude proposed by the report would be able to collect as much energy potential as there is available in the entire world's supply of recoverable oil.
The array is technically feasible, the report states. It does not require any massive breakthroughs in science -- this could be built within 10 years.
"The Sun is a giant fusion reactor, conveniently located some 150 million km from the Earth, radiating 2.3 billion times more energy than what strikes the disk of the Earth, which itself is more energy in a hour than all human civilization directly uses in a year, and it will continue to produce energy for billions of years," says the report.
And again, further on the report, the weakness of relying on foreign energy reserves is reiterated: "the U.S Department of Defense (DoD) has a large, urgent and critical need for secure, reliable, and mobile energy delivery to the war-fighter."
While the idea seems to make so much practical sense that it would probably not be undertaken in regular circumstances, because the expense could be justified as the price required for securing near limitless energy for the military might of the U.S armed forces, maybe -- just maybe -- politicians may actually consider embarking on such a monumental project.