Scheme for a 100% Passive 100% solar house for a cold climate

cllctr-beside-str-1.gifThis house may heat itself in a cold climate without purchased energy.  Although shown as 100% passive, in practice the house would have a fan to blow hot air into the house from the heat store, and a thermostat to control the fan for automatic temperature regulation of the habitable space. Manually operable dampers on suitable openings between the heat store and the habitable space would allow for manual temperature regulation during a failure of fan power.

The design of a suitable  thermal mass for the heat store may be seen at Free-standing column of stones for a heat store without fans.

The house has only one set of dampers on the air heater side, at the bottom of the air heater. These passive plastic film dampers prevent back flow of cold night air into bottom of the heat store.  No dampers are necessary at the upper opening  into the heat store from the air heater. The heat trapping structure of the upper opening will prevent leakage of the hot light air above into the cold heavy night air below, as long as the air heater, or the house, or both, are reasonably air tight. 

Upper dampers, if present would swing into the heat store during operation, where their operation would be inconvemient to verify, and would allow only awkward access for repair. The lower dampers swing into the air heater, where they should be easily visible, and allow easy access for maintenance, if the air heater is large enough for easy entry. The lower opening into the heat store from the air heater is via a cold trap, so that air on the inside of a damper made cold at night by conduction through the thin plastic film will not slide across the floor of the air heater and onto the floor of the inhabited space.