My father has heated and cooled his house for years with an air-source heat pump. Geothermal is essentially the same thing, except instead of using the air as your heat source/dump source, you are using the ground.
The downside to transferring heat to/from the ground is that heat is not easily conducted through dirt. (pipes layed in trenches). Whereas air-source heat pumps can easily transfer heat to/from the air, ground-source heat pumps need more surface area to transfer the heat.
But the huge upside... the ground is a fairly constant temp. Instead of trying to generate heat from -20C air, you're transferring heat from +12C ground. And instead of trying to cool (reject heat) to +30C air, you're transferring to +12C ground.
Several routes to go with the outside portion (the Wiki article covers it well).
The inside route... forced air vs. water....
Forced air is good if you plan to use it as air conditioning. Water, used as in-floor radiant heating, is a much better heating system. Easier to control 'zones' of the house. And heat at your feet feels much nicer than heat swirling around your head. You can actually keep the temperature of your house lower with radiant heating, because the act of heating your feet makes you feel warmer.
I think part of the big expense with geothermal is based on how the system is installed, and the labour for it... drilling a well versus digging a trench... If you have friends with connections, or you have knowledge and access to equipment, you can lower your costs. (when my father built his 30x40 shop, he bought a used backhoe... calculated that it would be cheaper for him to buy it and maintain it, instead of paying someone else to do all the digging, back filling, etc etc. And now he's got a backhoe to use around the farm. Lots of fun!)
The downside to transferring heat to/from the ground is that heat is not easily conducted through dirt. (pipes layed in trenches). Whereas air-source heat pumps can easily transfer heat to/from the air, ground-source heat pumps need more surface area to transfer the heat.
But the huge upside... the ground is a fairly constant temp. Instead of trying to generate heat from -20C air, you're transferring heat from +12C ground. And instead of trying to cool (reject heat) to +30C air, you're transferring to +12C ground.
Several routes to go with the outside portion (the Wiki article covers it well).
The inside route... forced air vs. water....
Forced air is good if you plan to use it as air conditioning. Water, used as in-floor radiant heating, is a much better heating system. Easier to control 'zones' of the house. And heat at your feet feels much nicer than heat swirling around your head. You can actually keep the temperature of your house lower with radiant heating, because the act of heating your feet makes you feel warmer.
I think part of the big expense with geothermal is based on how the system is installed, and the labour for it... drilling a well versus digging a trench... If you have friends with connections, or you have knowledge and access to equipment, you can lower your costs. (when my father built his 30x40 shop, he bought a used backhoe... calculated that it would be cheaper for him to buy it and maintain it, instead of paying someone else to do all the digging, back filling, etc etc. And now he's got a backhoe to use around the farm. Lots of fun!)
