Geo Thermal
Geothermal is another exciting technology that shows great promise. Heat pumps can gather the heat that exists just under the frost line all year around. Here in Rock Island, Illinois the ground temp remains 57 degrees through summer and winter.
The way it works? Ground loops carry either water or a special solution through the ground absorbing heat which is then transfered and concentrted via a freon loop. This heat is then delivered to a conventional blower system or even better, another liquid based system such as radiant heat.
Below are some links to sites that either sell or explain geothermal more completely.
