Solar cells atop these balloons provide electricity that cracks water to get hydrogen for lift and to power the fuel cells at night.

During this night cycle they'd dip lower into the troposphere to replenish their water supply by sucking moisture laden air through a condensing system. This water would be broken into it's base elements by the solar cells in the morning.

To save weight, the balloon itself could be used as a parabolic reflector to focus the sun's rays on a relatively small solar panel array situated at the top of the unit. The bottom half of the balloon could be mirrored while the top half would be clear focusing the light on the underside of this two sided solar panel maximizing the power output with no added weight. Motors would tilt the unit towards the sun at the optimum angle.

Theoretically these could stay aloft for years and be used to cheaply replace some orbital satellites for communication, weather monitoring etc.
-- doctorremulac3, Nov 21 2013

I generally like big floating semi-autonomous things, so bun for you.

How would you keep them located where you want them?
-- the porpoise, Nov 21 2013


You might be able to get away with just having them float around freely. Make them cheap enough that they're disbursed relatively evenly around the equator.

It might also be possible to do some station keeping by having them dip in and out of wind currents going in the direction you want. Dip into the jet-stream just long enough to get back on station relative to the other balloons.

In other words, I don't know. Hadn't thought that far ahead.
-- doctorremulac3, Nov 21 2013



random, halfbakery