When you make a solar panel really, really thin, it gets really, really light, too. That means you can build solar power into all sorts of technologies that couldn’t deal with it before — like military drones. They can’t be too heavy, but the military does have an interest in having them fly around for days at a time without refueling.

This isn’t just some futuristic, comic-book dystopian idea. The Atlantic reports that it’s really happening:

When we visited Alta Devices … they’d recently incorporated their solar technology into a drone wing. That could potentially extend the flying time of these unmanned aerial vehicles from a couple of days to much longer. While Alta is still in the early days of developing solar that can be incorporated right into these flying machines, it’s fascinating to think of a solar company that has to sell to military contractors, not eco-conscious homeowners.

In theory, this technology could be useful for stuff besides state-sanctioned murder, but the thing is that making solar panels that thin is quite expensive. And who has funding to buy really expensive gadgets? Oh, right, the military. In theory, though, the more the military invests in thinner-than-thin solar panels for their drones, the better the technology will be, and the sooner we can have our own personal solar-powered drones to watch over our children while they’re at the playground. And, you know, protect them from the other drones.