# Do you think it’s possible to make a power plant of the described kind?

We are working on a science project and try to engineer a power plant of a new kind. It is called Air HES (air hydroelectric station). The idea is described on our website.

Do you think it is possible to create such power plant? We already consulted some scientists (professors, etc), and most of them consider the idea realizable, with a few remarks. However, we still collect feedback, and we will be very glad if you have something to say about the physics concepts involved.

Air HES provides a downstream (water‌’s outflow) 1, upstream (water‌’s inflow) 2, conduit (pipe, penstock) 3, the turbo generator 4, mesh, fabric or film surfaces 5, airship (air-balloon) 6, and the fastening ropes (tethers, lines) 7. The airship 6 lifts the surfaces 5 at the height of near or above the dew point (condensation level by ARL sounding, base of clouds) for current atmospheric conditions (typically 2-3 km). There supercooled atmospheric moisture begins to condense (or collect LWC from clouds) on the surfaces 5. The drainage system on the surfaces 5 assigns the water in a small reservoir (upstream 2), where water under pressure from whole hydraulic head (2-3 km) flows through the penstock or conduit 3 to the downstream 1 on the ground, producing electricity in the turbo generator 4.

(image from Air HES)

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You're trying to sell this thing but you still feel the need to ask on an open website if it will work? –  dmckee Jun 17 '12 at 22:19
didn't look at it too carefully, but your example system has a cost of \$10000, with \$5000 being helium. Then you say operating costs are almost zero. You probably ought to look up helium leak rates. –  user2963 Jun 17 '12 at 22:49
Not to mention, the world supply of helium is woefully insufficient to supply a fleet of such power stations, and hydrogen would bring plenty of new difficulties. –  user2963 Jun 17 '12 at 22:50
You need to estimat the best-assumption amount of condensation per second--- you will probably have too little fluid to make electricity, and the water flow will be miniscule, or else weigh down your balloon. What you are doing is extracting energy from rain. –  Ron Maimon Jun 18 '12 at 5:31

While such a power plant is principally possible, I see several engineering issues.

A rough calculation shows me that your 20kW, 2km plant will have to disspipate 2,5 kW condenstation warmth, this could be an issue in cold air - though convection will cerntainly help here.

The engineering issues are: The hose has to withstand the wind drag on the balloon or kite -> heavier, bigger baloon

What happens in case of failure of one part, e.g. 3km of hose falling down?

Helium leakage (as indicated in one comment)

Freezing on the condensor, when it gets really cold

Freezing in the pipe

The hose has to withstand 200-300 bar at the lowest point - did your calculation for cost and weight take this into account?

My gut feeling as an engineer is that it wont happen soon. However, when I was doing the basic math on your proposed system, I was surprised at how small the amounts of water neccesary to achive some effect were.

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