If you are looking for a more environmentally friendly alternative to the traditional methods for home heating, you will probably consider both solar and geothermal options. Each of these relies on a great renewable resource to function and can be an excellent option depending on your specific circumstances. Of course, both geothermal and solar heating have limitations as well, so it is important to take these into account when you are evaluating your options.
A geothermal heating system works by extracting heat from the ground and transferring that to the air in your house. This occurs when heat is absorbed by a fluid flowing through a closed loop of pipes beneath or next to your home. The fluid then returns to your home, where the heat is extracted by a compressor and distributed throughout the house by an air handler.
This uses very little energy relative to a conventional heating system, as you only have to power the condenser and the air handler. The heat is not generated by the system but merely harvested, so total energy costs are quite low. However, the installation cost of a geothermal heating system can be many times what a conventional heating system would cost.
Solar heating relies on solar collectors to gather the heat from the sun. This heat is then passed into a system of heat pumps and heat exchangers so that it can be adequately distributed throughout your house. The installation of heat collectors, of course, is quite expensive as well, while the cost of running the system is generally low just as with the geothermal heat pump.
One advantage to opting for a solar heating system is that you can lease the equipment rather than buying it in some areas. This means that you do not have to pay the high installation costs and only pay a monthly fee to use the equipment which is usually comparable to what an average heating bill would be if you had a furnace.
But you also have to keep in mind that you need to have enough space to put up an adequate number of solar collectors to keep your house warm all winter. This often means giving up a lot of land, and if you have a lot, that is fine. But it is still something you need to take into consideration. Also, you need to make sure that the area you live in gets enough direct sunlight to make solar heating a viable option. Otherwise, you will be paying to run a backup system much of the time anyway.