Once again I’m dealing with refrigerants and AC problems. I’m paying $60/lb for R-410 which replaced freon (R-22) that will be fazed out by 2020. I could probably pick up R-410 for under $10/lb but licensed HVAC companies have to have a paper trail showing where their refregerant was procured.

R-410 has its own disadvantages. It stays in the atmosphere a *long, long* time increasing the greenhouse effect. My guess is that eventually, everyone will switch to CO2. Could get on the leading edge of that trend in a niche market for green housing.

So, basically, design a passive solar house as a proof of concept with strategically placed thermal mass for heating in the winter, covered by tons of earth and a roof garden. CO2 HVAC, water reclamation and filtration, whole house HEPA air filtration, solar heated hot water, photovoltaic power generated by a flexible thin-film grid canopy over the garden. Patio should be cooled with Arab cooling towers, which are basically passive downdraft evap. Gardens should be based on low water consumption concepts from the Desert Botanical Garden.