Lots of people have second homes. Lots of people have green second homes, replete with energy-efficient windows, wood stoves, and loads of insulation. And second homes are a great proving ground for technology or design (or a lack of it!) that you might not be ready to live with everyday.
But there's no getting around it: second homes are not inherently green. They take more stuff to build; more energy to heat and to cool; and you have to get to the second home somehow, too -- and that usually means time in a carbon-spewing car.
image by laure8354 via sxc.hu