Paul, I would be so dismissive of Benfords ideas,
here is the link Gregory Benford

Regarding your point on flywheels - it is true they are dangerous
but one idea being developed is to make flywheels from compressed composite material that would disintegrate into dust. (Already in 1890
when the InterUrban railway was being built in Vancouver, the design incorporated energy storage in a flywheel)

ALso your point on pumping water uphill, is another good energy storage solution, (one example in the US being Raccoon Mountain )

it is interesting to see how efficient small wind turbine might be. In Ontario the Bruce peninsula which gets a lot of wind from the lakes there is a large wind turbine which generates enough power for 500 homes (about a 1/4 of the inhabitants of the peninsula).

ONly a few months ago, I noticed Canadian tire selling small wind turbines as well as solar roof top systems. Since our house gets alot of
the southern sun - its too hot to even sit on the deck in the summer.
I had been considering trying out a system. Now ideally if the govt gets its act together and comes up with a carbon trading system, homeowners with such systems should get some credits..