I was feeling pretty good about my old Berkeley home’s energy efficiency…it’s well insulated, not too drafty by 1924 standards, is solar-powered, and is inhabited by family members who,  like it or not, wear sweaters and hats instead of cranking the thermostat up above 62.  Then I read about passive zero-energy homes and am feeling green with envy indeed.

A passive home is built to maximize passive solar gain and is uber-insulated and ventilated.  Air warmed by nothing more than bodies and cookstoves stays indoors rather than heating up the outdoors.  In the summer, the design works in reverse, keeping the house cool without air conditioning.

The Landau family is building a passive home without a furnace in frosty Vermont. They’re spending an extra $50,000 more than it would cost to build a conventional house, but expect to make that money back in energy savings within 10 years.  Watch a video showing the Landaus house being built here.

Passive homes are a novelty in the United States but are old hat in Europe, where the cost of building a passive home is only 2-3% higher. (But you probably knew that already–name any energy policy or practice you want to see adopted in the U.S. and, odds are, it’s been in place in Europe for years).

Most of us aren’t building homes from scratch like the Landaus, but there’s plenty we can do to make our old houses way more efficient. And with a federal tax credit and a host of local rebates available now for home energy retrofits, there’s no time like the present.

–Erica Etelson

Posted by Danny Kennedy

Danny Kennedy co-founded Sungevity and now serves as strategic advisor. He is an internationally recognized opinion leader on climate and energy issues. He is the author of Rooftop Revolution: How Solar Power Can Save Our Economy - and Planet - from Dirty Energy (2012), a book that has been described as the clean energy manifesto for the next greatest generation.