"It was a place to come and pretend to be hippies on the weekend."
That's how programming pioneer Loren Amelang explains his back country California property, where he originally built a tiny cabin inside a sheep barn as a country retreat. But when it came to building a larger, more permanent abode—he created a rather wonderful, off-grid structure that looks like it is straight out of a post-apocalyptic Mad Max-style movie. It uses passive and active solar power for electricity, hot water and even some space heating needs, with the rest of the heat being provided through sustainably harvested local fire wood.
Featuring a large greenhouse on the south side, the whole house acts as a passive solar heat collector—with large amounts of thermal mass inside the greenhouse to collect and store that heat for later distribution. So far, so normal. From high thermal mass trombe walls to high tech modeling for passive solar building design, we've covered many options for buildings as passive heat collectors. (Note that passive houses and passive solar design are not the same thing.)
But where Amelang's house takes a turn toward the unusual, is the use of the greenhouse as an active solar space heater which sucks warm air through a tunnel at the top of the greenhouse and then either recirculates it into the house itself, or vents it out into the open air by means of a computer controlled system of shutters.
The system is actually even more interesting than that, because in its fully functioning form, it is supposed to first collect energy from the top of the greenhouse at a different vent, then pass it down behind the high thermal mass trombe wall, through a tunnel underneath the greenhouse, and then up through a glassed-in solar air collector inside the greenhouse before passing up to the roof. But that full system is not currently functional due to some missing glass.
It's all very fascinating stuff, but as Amelang himself notes, it is somewhat intrusive in terms of having to have large glassed-in boxes on the front of your house. Either way, it's created a pretty unique space—and the fact that he can grow tomatoes in December is just an added bonus.