Propane vs Passive

Take it as a sign of America's home heating bill sickness (as in, we're sick of paying them): Today's most-emailed story over at the New York Times is a feature on passive houses, homes so efficient and tight they require no fuel source other than human bodies. As a couple of colleagues have pointed out, the story was frustratingly short on specifics--the key to the whole rig seems to be a mysterious heat exchanger shaped like a styrofoam cooler--but apparently that hasn't stopped a whole lot of readers from dreaming of a fuel-bill-free world. I rooted around and found a few more details at the Passive House Institute, an Urbana, Illinois-based group, that's got a good web site and a book, Homes for a Changing Climate. If you're wondering how propane and heating oil prices have fluctuated in the past year, check out the Energy Information Administration's heating oil and propane update. I also like John Bogdanski's home heating site; he ain't the greenest freak in the world but the Boge peddles good basic info. The most intriguing device I've run across lately is the EcoFire Super-Grate, which promises to turn your fireplace into a high-efficiency heater. Anybody tried one of these things? Do they work? Let me know.