The costs of residential heating using conventional, solar and geothermal energy were calculated for a number of locations throughout the United States using life-cycle costing methodology. Using these costs, regions and applications are identified which show the most promise for near-term commercialization of geothermal and solar energy. Equally important, areas and applications are depicted which are not likely to be promising for solar or geothermal heating in the near-term. The regions showing the most immediate promise for solar heating occur in central Nevada, Utah and Colorado. These regions are characterized by high levels of insolation and high annual heating degree-days. For more information on this resource, please see the link provided.