Heatpumps For Everyone

Geothermal is interesting.

I saw an article in New Scientist recently about a new technology which uses large floats which are mounted to simple mechanical pumps that are attached to the seabed. The waves allow the float to rise and fall which pumps water onshore up a hill. The water then falls down through gravity and drives turbines.

Simple and cheap.

If you assume that the cost of building huge reservoirs with turbines at the base is simple and cheap, then yes.