Living nr Ottawa, Ontario, Canada. It gets mighty cold here in the winter.. heating is generally on from October through March. 2400sqft house was built in 1991 to R2000 standards. Geothermal (Waterfurnace Premier AT) was installed at that time. Last April, the compressor and coaxial heat exchanger were replaced.
The Ontario government is hiking hydro rates to unprecedented levels to pay for so-called "green" technology for power generation. Whether or not you agree, the bottom line is, with hydro rates set to double in the near future, is geothermal still worth it from a purely economic point of view? My bills right now are $350/month and I have propane for hot water, the kitchen range and the dryer. I have a woodstove in the basement which I try to use 24x7 during the heating season. My lights are nearly all CFL (except for those lights on dimmers and external lights) and I try to turn them off when not in use. Electronics are all modern and "sleep" when not in use. Short of cutting power to electronics (marginal savings), I think I've done what I can to minimize hydro usage. The main cost is running the geothermal unit.
I've been considering replacing it with an oil furnace (also considering propane as I've got the tank and infrastructure installed already). Ideally, I'd like to have a combo wood/fuel appliance, but I've been told that gas/wood units are not allowed in Ontario (dunno if that's actually true?) which might limit me to wood/oil. There are also lots of cheap furnace/tank combos on kijiji right now as many folks are switching to nat. gas (will never be available in my area).
So, my question comes down to this? Without considering the social and environmental impacts (those are personal considerations and outside of the context of this post), what is going to be a more cost-efficient solution for the next 20 years? I know geothermal is considered 100% efficient, but if it still costs more to run it, I'm no further ahead (and actually behind).