Here's an idea so crazy it might work: a solar plant on the Moon. Specifically, an 11,000km long solar belt that spans the Moon's equator and sends energy back to Earth with lasers and microwave power.
Japanese firm Shimizu is calling their lunar solar power generation concept the Luna Ring and it's brilliantly ambitious. The way the Luna Ring works is by gathering solar energy with an 11,000km long solar belt across the Moon's equator that'll be transmitted to Moon-based energy conversion facilities. The converted power will then be beamed to Earth-based facilities with laser power and microwave power. Once on Earth, we'll be able turn all that power into electric power for our power grids or hydrogen fuel.
Robots will handle the lunar-side construction with most building materials coming from the moon. The benefit of having solar panels on the Moon is that it eliminates inefficiency due to bad weather and allows it to achieve 24/7 continuous power generation. Oh, and the fact that we'll have a freaking power plant on the Moon sending lasers at the Earth isn't anything to sneeze at either.
If this Luna Ring ever gets built it'll join a growing number of robot Moon bases in the works. Which will obviously lead to Robot Revolution with all the robots banding together and hijacking the Moon - stealing all our power in the process. [Shimizu via Inhabitat]