Financial mechanism needed for passive solar construction

How can we create a system to finance needed passive solar technologies up front? I've long dreamed of building the ultimate ecologically friendly dwelling; rammed earth construction, cooling drawn from underground for use in summer; and heat stored for winter use in large, highly insulated masses of earth (also underground). The heating / cooling systems could be adapted for conventional homes as well, by heating a larger volume of earth. Hot summer air is cheap! I envision a system where the funds are provided up front, plans, site, and progress are evaluated by an administrator, and a conventional mortgage results for the property when construction is complete. If the person defaults, sell the property and reinvest the funds for another similar project. Can we do this?