"That is why I believe that cheap production of hydrogen gas is possible using the common ultrasonic devices that chemistry labs currently use to speed up / catalyze chemical reactions." said Donuel.

But that doesn't produce any energy, it merely changes it from one form (electricical, mechanical) to another (chemical). You still have to produce the input from somewhere, and the only possible non- fossil sources are from outside (solar- this includes wind, tidal and wave energy since they are powered ultimately by the sun), or internal, that is nuclear (geothermal, fusion or fission).

Of those, solar options and geothermal energy are rejected as uneconomic (nobody having priced the Earth), fission is filthy (google for Dounreay, Chernobyl, Three Mile Island, Sellafield, etc.), and fusion hasn't worked yet (except uncontrollably, as a weapon).

JiK... temperatures are high, but the pressure is low, so it's almost like a vacuum flask- the idea is that there isn't sufficient conduction from the plasma to the metalwork to make cooling a problem.