Our Green Streets Blog

Nabih Tahan, an architect in Berkley, California has built a “passive house” that captures and recycles heat produced in the home, thus eliminating the need for a furnace altogether.  Essentially the house is very well sealed, making forced air ventilation a necessity.  The heart of the system is a heat exchanger that strips the old, stale air of its heat and uses it to heat the incoming fresh air.  Tahan explains that this concept is best applied to new construction or to major remodels, due to the extensive sealing and insulation required.

“By doing smaller insulating renovations, you can improve energy consumption and you’ll definitely make a difference,” he said. “But to get to Passive House standards, you really have to either rip out the outside or the inside of the house.”

This in not new technology.  The first passive house was designed and built in 1991 by German Physicist Wolfgang Feist, and today there are an estimated 15,000 passive houses worldwide, mostly in German speaking countries.  In Darnstadt, Germany, outside of Frankfort, Berthold Kaufmann’s house, “and others of this design get all the heat and hot water they need from the amount of energy that would be needed to run a hair dryer.”

By all accounts the technology is amazingly effective, rendering year round comfortable living at a tiny fraction of what it costs to heat and cool a traditional home, with no drafts, no thermostat lag, and remarkable temperature stability.

“You don’t think about temperature — the house just adjusts,” said Mr. Kaufmann, watching his 2-year-old daughter, dressed in a T-shirt, tuck into her sausage in the spacious living room, whose glass doors open to a patio. His new home uses about one-twentieth the heating energy of his parents’ home of roughly the same size, he said.

“This is a recipe for energy that makes sense to people,” Nabih Tahan said. “Why not reuse this heat you get for free?”

Lowering heating bills while easing carbon emissions seems too good to be true.  The fact that both these ends can be met while actually improving the livability of spaces makes this a solution that builders and architects in the United States should be incorporating into all their new construction and renovations.