Airborne solar wind energy systems (ASWES)

[PierreB]

@dougselsam

Pierre: That is amazing - you used only solar hot air and got off the ground?

Yes. I also have videos of the TV show, but I can’t make them public.

@dougselsam

I think you are lucky that you did not get into a thermal updraft.

Certainly there can be a danger, but I had some margin. The aerostatic thrust of the balloon was only a quarter of my weight. This is explained on

Solar balloon jumping

I conceived and used the solar balloon jumping as a (dangerous) game, not for any other use. The balloon accelerates while it gets up during the 10 m rope. The obtained kinetic energy is: 1/2 V² x m where V is the balloon vertical speed in m/s (here 3 m/s), m is its mass (envelope = 10 kg + air = about 450 kg for a 400 m3 balloon = 460 kg). 1/2 x 9 x 460 = 2017 J. The buyoancy is 200 N. So the weight is 800 N - 200 N = 600 N. The jump height is 2017/600 = 3.45 m. A 400 m3 double envelope ba…