A steam plasma. A 50x1cm steam plasma tube at 4 atmospheres does Molecular Nuclear Fusion.
1 H2Op+TU->E3+L+X-ray no solid, radioactive waste
10-12cc of regular water will drive the plasma tube for a year. Releasing 2.4MW of heat – not the 1.2 a free plasma would produce.
A thermoelectric generator will produce 144kW of DC: power electronics converts this into frequeny matched AC.
A small helicopter only need 45kW. So we produce no CO2 or NOx, from very, very little regular water. 10-12cc.