this (pasifhaus in german) is the name given to the german creators of a low-energy-consuming house. it requires little or no energy inputs, relying on the heat of the sun, directly shining into the house, or on the internal heat put out by people. it is sealed against the outside air, except for a special heat-exchange ventilation system. the cool air coming in from outside passes right next to the tube carrying the warm inside air out. 90 percent of the heat is conserved by passing to the incoming air and returning to the house. these houses are a bit more expensive to build than normal houses, because there are special fittings and seals around windows and doors. and there is a possibility they can be created for staying cool in hot places, too.
to catch on in the US the term "passive house" will never do. anything that reeks of passivity or the natural (or any diminishment of the heroic individual) is morally repugnant to americans. "tough house" or "success house" might work, however.
passive houses were written up in the new york times on sunday, i think.
there is another kind of alternative heating using air shafts into the earth and convection currents inside and around the house, but i forget what this is called.