The Snowmass, Colo.-based Rocky Mountain Institute is a nonprofit dedicated to promoting sustainability in three main areas: energy, transportation, and buildings.
At about 8,000 feet, RMI founder Amory Lovins' house, which is the nonprofit's original headquarters, serves as a showcase for the kind of ultra-efficient housing that is possible today.
Though it was built years ago, it has recently been renovated and now includes a new, large set of solar panels--on top of a set of panels it already had--that allow the building to produce more energy than it uses.
The house is filled with a series of systems designed to get the most out of the building and to make the space as livable as possible.
As Lovins is apparently fond of saying, people who live in energy-efficient houses need not skimp on hot showers or cold beer.