We currently have a hot water baseboard system we do not use because the propane furnace is too expensive to operate. It was installed about 1990 and since then the domestic hot water was replaced with an electric HW heater when the boiler went bad. We presently heat primarily with a wood stove. As we get older we would like to upgrade to solar, geothermal or other low maintenance models as we can sort through the recommendations. Any ideas? Thank you.