[edited with FlyingToaster's option on March 11 2011]

A large O shaped blimp with an ultralight pair of co-axial contra-rotating kite wind-turbines, runs an electric (dynamo) generator. The blimp carries a small salty water supply which is turned to Hydrogen and oxygen via electrolysis using graphite electrodes. Sea water is pumped up at the amounts being consumed.

Run from a boat (or ship) this would be extremely low cost. The hydrogen, stored in secondary blimps could be stored above, and gathered to a land power station. The minerals from the brine can also be periodically removed and used.

Benefits: Safe: (Hydrogen high up in sky), High and constant wind power, Low cost energy storage, Low cost construction.

Drawbacks: Hydrogen leakage (not that bad - as demonstrated by the Zeppelins before the Hindenburg) Electrolysis not efficient (debatable down to 20%!) Hydrogen motors for electric generation costly? Not sure... probably low cost conversion of a gas turbine to use hydrogen...

From WkPDia: NREL found that a kilogram of hydrogen (roughly equivalent to a gallon of gasoline) could be produced by wind powered electrolysis for between $5.55 in the near term and $2.27 in the long term.[7]

----

FlyingToaster's option: Have the electrolysis done at sea level, and the hydrogen pumped up in lightweight pipes.
-- pashute, Mar 01 2011

Chloralkali Process http://en.wikipedia...Chloralkali_process
keep Cl2 in heavy industry where it belongs!!! [cowtamer, Mar 03 2011]

Same as toast's idea, but with electricity and a copter instead of kite (ingenious) http://news.bbc.co..../nature/1248068.stm
[pashute, Aug 12 2011]

I like the idea but electrolyzing brine results in chlorine and hydrogen -- nasty stuff...perhaps this will work nicely in the great lakes, though
-- cowtamer, Mar 03 2011


//blimp kite// sp. "tethered blimp"

Surely the weight of a pair of electric power wires plus a lightweight tube for carrying H2 along the tether would be much less than the weight of the O in the H2O plus a heavyweight tube for carrying said H2O plus the weight of an electrolyzing gizmo at the blimp end... ie: put the electrolyzer on the boat.
-- FlyingToaster, Mar 03 2011


But then the blimp looses elevation, here it builds its own, and is safely stored high above.
-- pashute, Mar 03 2011


nah, you put a lightweight tube up to the blimp for H2, as opposed to a heavyweight tube for water.
-- FlyingToaster, Mar 03 2011


As soon as I saw //Sea water is pumped up// I knew this was a [pashute] idea.
-- lurch, Mar 03 2011


OK, I'll put that as an option.

Obviously pumping up water is a theme of mine... so I didn't think of pumping up hydrogen.
-- pashute, Mar 11 2011


why even pump it up? no one bats an eyelid twice at huge oil refineries (until they explode). Think it would be personally reasonable (and cheaper) to just store the hydrogen on the ground. Not to mention for efficiency it has to be stored at high pressure.
-- metarinka, Mar 11 2011


//has to be stored at high pressure// Well... as long as I have a vested interest in this... Why does it have to be stored at high pressure ? Maybe it's a blimp refueling station or a full-service rotate-your-gasbags shop.
-- FlyingToaster, Mar 11 2011


link to analogous idea but with electricity and copter replacing hydrogen and blimp
-- pashute, Aug 12 2011



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