Gas heating by electric arc (see lightning) is the most efficient heating means, yet a table is hard to find.
It is known that to heat one litre of water +100*C in one second consumes 456kW.
One litre of Carbon Dioxide CO2 when heated +30*C to +100*C in one second delivers to the turbine a drive force in excess 9,000 bar.
A 60% efficient turbine receiving a flow of 9,000 bar per second produces 600kW,
Gas heating may be arrived by passing the CO2 through hot water, but its not known if such can be achieved by arc heating, therby reducing parts need.