It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "IMM" saying
something like:

You could have a large tank at high level and one at low level. The mains
water turns the genny to produce power to heat a thermal store of water.
The genny turbine would have another pump on the same shaft. This pump,
pumps water from the low tank to the high level tank. When the high tank is
full the water from the high tank is released to turn the genny and flows
into the lower tank. Start all over again. You are getting the power to
raise the water free ( the water companies pumps in fact).

That's a wonderful way of wasting the precious resource of clean water.
--

Dave