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One of the world’s most ambitious plans for harvesting clean energy is largely stuck in the lab, despite decades of work and tens of millions of dollars in research spending. It faces many barriers, but one is particularly vexing: the giggle factor. Many people who hear the idea think it’s loony.
The concept, delicious in its brashness, brings to mind an early James Bond flick: shoot big pieces of solar-panel arrays into space, assemble them in orbit into massive power plants that are miles wide, let the floating facilities collect space’s intense sunlight and convert it into electricity, and then beam that extraterrestrial juice—ray-gun-style—back down to an energy-hungry Earth.
As with many alluring energy technologies, the hurdle doesn’t appear to be the underlying science. Panels on rooftops already turn solar energy into electricity, and several experiments have transmitted electricity through the air. The impediments are scale, which would need to balloon, and cost, which would need to plummet. Given the world’s vast energy needs, harnessing meaningful amounts of solar power from space would require shooting solar-array components into orbit multiple times a day, over years, some studies suggest. And it would cost tens of billions of dollars.
Phil Chapman, a former NASA astronaut, is a longtime space-solar proponent. He resigned from NASA in 1972, in large part because he disagreed with the agency’s decision to move forward with the Space Shuttle. By eclipsing another mission he was working on, the shuttle was killing his own chances of making it into space, he concluded. In addition, he says, he objected to the shuttle’s use of technology he regarded as outdated. “I thought it was a stupid idea,” he says.
Today, it’s doubters of space solar power who are misguided, he says. If solar power were harnessed at large scale in space, he says, it could prove cheaper, more reliable, and more productive than solar power on Earth, which today serves up significantly less than 1 percent of the electricity the world uses. Chapman also contends that if the industrialized world doesn’t develop space solar power first, other nations will, with potentially serious national-security implications. Over a Mexican lunch in Phoenix, where he lives, Chapman warned: “The consequences are sufficiently profound that we simply can’t afford to let hostile nations develop this technology.”
Chapman himself cites the giggle factor as perhaps the most significant challenge facing space solar power. Giggles aside, however, some prominent names have been looking into the concept. Among them: NASA; the Japan Aerospace Exploration Agency; and PG&E, a power company in California, a state that has mandated that utilities ramp up their production of renewable power.
Interest in space solar power is growing. Over the past two years, solar power—the earthbound sort—has experienced a massive price drop, raising the possibility that even solar panels shot into space might prove less ridiculously expensive than previously presumed. Meanwhile, though interest in space solar power traditionally has come from long-industrialized players such as the United States, Japan, and Europe, now it’s coming particularly strongly from two new kids on the block: China and India, both of which have soaring energy appetites and grand geopolitical ambitions.
Here’s how space solar power would work. Large pieces of a space-solar-power station would be shot from a launch site on Earth into space. Once in orbit, they’d be assembled into facilities that likely would be miles wide. (Proposals differ about the setup and the particular solar-capturing technologies the facilities would use.) Freed from terrestrial limitations of clouds, bad weather, and nighttime darkness, the spacecraft would harvest sunlight essentially 24 hours a day. They’d send the electricity they produced back to Earth either as microwaves or as laser beams. Back on the ground, according to most designs, that energy would be caught by similarly massive agglomerations of mesh: huge rectifying antennas, or, in the lingo, “rectennas.” From there, the electricity would be fed into the grid.
Studies have found all of this is technically feasible. A 2011 report for the International Academy of Astronautics concluded that space solar power could reach working at scale within about 20 years—if governments and investors committed to ramp it up.