Power is similar. Maybe you just use solar and turn the drives off when it's cloudy. With enough distribution throughout the world, it will probably be sunny somewhere.
I haven't done the math and I'm not saying it will work out favorably. I also don't have a use case for 95% availability. (That's two weeks a year where your data is gone!) But it's something that someone with the right needs could consider, and maybe come out ahead of someone shooting for 5 nines and drives that aren't covered in snow.