That’s not accounting for the inefficiency of turning heat into electricity in the first place (turbine generation is about 90% at utility scale) or turning photons into usable electricity (photovoltaics are at about 20%). And with turbines, you have to account for the inefficiencies in processing the fuel to get it to that point.
The whole universe is just an entropy generator and we’re gonna lose a lot of useful energy as we try to manipulate it.