Space-based solar power has long promised to be a cheap and eco-friendly source of energy for Earth, and for just as long, it hasn't happened. This new concept for a giant solar microwave space flower may look crazy, but NASA liked it enough to throw some money at making it real.
Space-based solar panels make a lot more sense than Earth-based solar panels do for two reasons. First, there's no night in space (far enough into space, at least) so you can generate power continuously. Second, there's (virtually) no atmosphere in space, so solar becomes very efficient. And also, birds won't nest in and/or poop on them. Okay, three reasons.
At the same time, space-based solar panels make a lot less sense than Earth-based solar panels do for two reasons. First, it's absurdly expensive to send anything into space at all, solar panels included. Second, you'd either need an improbably long extension cord to get the power back down to the ground, or you need to develop a wireless power solution. And also, they're at risk of being stolen by aliens. Okay, three reasons.
This new concept called SPS-ALPHA (short for Solar Power Satellite via Arbitrarily Large PHased Array) tackles all these problems by using a bio-inspired, modular design. What looks like a giant flower is an array of small (110 to 440 pound) individually controlled mirrors that redirect incoming sunlight down towards the disc at the bottom of the satellite. The back side of that disc is covered in photovoltaic panels, while the front side (the side pointing towards Earth) is covered in microwave transmitters that send power (in the tens to thousands of megawatt range) back down to the ground using beams of low-intensity microwaves.
It all seems fairly fantastical, but, after seeing it pitched at the 2012 NASA Innovative Advanced Concepts, the agency has enough confidence in the idea that it's decided to fund some design work and small-scale prototypes with the eventual hope of sending something operational into low-Earth orbit for a flight test.