We've already had quite a few conversations here about square footage and its relation to the greeness of a home. So, forget for a moment that the Eco Home by Diseño Earle is 7,000 sq. ft (what!?).
Instead, let's take a look at some of its cooler features.
It is designed so that natural features (breeze, a 12-inch-deep canal of water, geothermal, etc.) can heat and cool the home. Its solar panels are placed so as to receive the most possible exposure. The pool will be filled with saline water, which means it doesn't need any chemicals. And, its got a pretty intense rainwater reclamation system.
Read more about it at EcoGeek.