Passive solar design is quite possibly one of the most efficient building techniques ever. Yet we rarely see the conscious implementation of this timeless way of building structures which are in-tune with the energy balance of their environment.
It’s a perfect example of how innovation is also about the challenge of adoption. Thomas Wagner has met that challenge head on by building a passive solar home in Palo Alto in 1982. He graciously hosted a potluck and gave a tour of his home that keeps warm in the Winter and cool in the Summer with little to no active heating or cooling.