the earth is negatively charged and space is positively charged ,measured to earth from the ionosphere there is an electrical difference of 200kv . if you could build a helium ballon big enough and have a light and long enough wire conductor hanging from the ballon positioned in the ionosphere to earth could we use free electricity? granted we would have to rectify from dc to ac and then transform to a lower voltage but it sounds feasable to me. the big question is how much usable current is available . i cant find any research on actual curent estimates only voltage. what do you think?