Or, fossil fuels provide the greatest energy flux per unit infrastructure of any option in the whole past and future of humanity and are as good as it gets and until they run low there is no reason to use anything else.
I am confused as to what you meant. I couldn’t google what you meant by energy flux, if you don’t mind elaborating?
Watts per unit of infrastructure machinery necessary, including ancillary things not in the actual engine. Not joules per unit fuel.