I built an off-grid home which produces between 5 and 15 kWh/day with a 1.5 kW solar array and 1 kW wind turbine. My energy budget is 6 kWh/day unless it’s a productive day in which case we can get a little wasteful. The architectural style of my 3200 sqft home is a hybrid of gothic and neoclassical, which is like the polar opposite of typical modern-looking off-grid homes. The passive solar and thermal mass didn’t really cost much more than a typical home, though the spray-foam insulation was significantly more costly and the active power generation components totaled around $75k including panels, turbine, evacuated tubes, batteries, inverter, pumps, breakers, etc., and related infrastructure.

To generate 52 kWh/day reliably, you would need at least a 10 kW nominal array, bare minimum (20 kW more likely). Just for the panels, that would cost in the neighborhood of $50k to $100k, not including mounting, tracking system, wiring, grid-tie inverter, breakers, and everything related to that geothermal system and solar thermal. On the website, they claim the cost in excess of a typical home of the same size was about $150,000 before rebates, or about 50% more expensive.

Also, just from looking at that photo, I know that little effort was expended in architectural energy considerations. A ranch is much less efficient than a two-story of the same floor area. In a two-level home, you require half as much roof and floor area to insulate and have more south-facing window area to collect passive solar heat. Also, if they have passive solar and solar thermal and are well-insulated, then I don’t know what the purpose of the geothermal system is.

I would have reservations about this house performing as advertised.

check it out and leave your thoughts!

A little dose of healthy skepticism.

Note to Neumann Developments: post proof or you will soon learn that there IS such a thing as bad-press.