But one thing that really would help the movement at large is if it concentrated on cost-effective solutions.
Solar-thermal water heating is actually cost justified for ~half the people in the U.S... The panels are essentially black painted aluminum sheets with copper pipes in a serpentine pattern flowing in metal-to-metal contact with the sheets. It's extremely low tech, which means that the panals cost very little compared to PV panals offering similar energy yield. So the water could be heated and pumped to a large water tank. Even if the tank needed further energy input to heat the water to the desired temperature or maintain the desired temperature, the panals would still reduce the energy needs of the house.
Of course the final system costs are not so very great of a savings vs. PV. Installing in an existing home means A LOT of plumbing work, as well as roofing work.
If solar thermal was pushed for new construction, it would be a cost-justified improvement for the house at large (due to the fact that the plumbers and roofers would already be working on the house anyway, and the house would be a skeleton for the plumbers to work with).
It wouldn't work for AK, but it would be cost effective for most people. This would be good for the environmental movement - telling people about choices that save them money makes you friends, especially if those choices require no sacrifices... and that would have a real chance. Environmentalists rarely support solar water heating, however... because it doesn't do as "much good" as PV... even though PV costs several times as much and could never be considered a competitive option as long as a location is on a grid (PV does make sense for extreme remote locations, since running power lines costs).
