By 2025, if predictions are correct, solar power is going to be as cheap as natural gas. But we’d still need a place to put all of the solar panels, and that could be a problem. To power the planet, that would require a lot spare land. The results might not be pretty.
One possible way forward: solar on the surface of the Moon. Under designs sketched out by Shimizu, a major Japanese construction company, we could create a “Luna Ring” that is 250 miles wide and 6,800 miles long, and cover all of Earth’s energy needs just like that. Cables underneath the ring would gather power to the Earth-facing side, and then beam the energy our way using microwaves and lasers. Shimizu believes the scheme, which it showed off at a recent exhibition in Japan, would virtually solve our energy crisis, so we never have to think about fossil fuels again. Check out its video here:
Suffice to say, there’s a long way to go before the Luna Ring has even a shot to becoming a reality. But Shimizu has some practical ideas. Naturally, the construction company believes it could build the concrete foundations using robots guided from Earth, and says that beaming the power back home wouldn’t be difficult. “Rectennas” on land would convert microwaves into immediate D.C. current (the efficiency of this process might be a consideration). The laser light would be transmuted to electricity using photoelectric cells, or stored in hydrogen fuel.
This is all rather fanciful, and there’s a good chance the company means it to be as much of a marketing stunt as a real project. But at least it’s thinking big about the future. By 2035, we will really need solar, and it’s likely we’ll also need a whole lot of space to put it–if not the Moon, then somewhere else that doesn’t command high real estate prices. Shimizu says construction could begin in 2035.