600 bucks a year

That's what the utility bills are for this house. I'm a bit jealous, I confess, and I'm frustrated that we don't do this more often, but it takes a motivated client, an informed designer and a careful builder.

This is the Green House in Jamaica Plain, which I had the opportunity to visit yesterday. It is a full gut rehab of a wood framed commercial building and was renovated to PassivHaus standards of energy efficiency. I can quibble about some of the details and architectural decisions, but that is all trumped by the absurdly low carrying costs for the plug loads, lighting and domestic hot water. It has no direct heating systems, although they have made provisions to install an efficient heat pump.