If we ran out of fossil fuels which could replace them.

Question

Hydroelectric
Wind
Solar
GeoThermal

No single one of these resouces, at their current levels, could totally replace out energy consumption.

Hydroelectric

yeah but which could almost do it

None of these. To even come close they would all have to be combined and have much more capital invested into them.

Solar is the only energy source available world wide. This does not address all the matereial products we get from Petrochemicals, such as plastic, etc. as such none of the choices are viable.