Geography used to be considered destiny, but this once-popular notion that terrain and climate drove history has gone out of fashion. Now a new generation of environmental historians are bringing hard, physical materiality back into mainstream history with a more nuanced approach, looking at the historically situated interaction between people and their physical environments.

Green buildings aren’t just the energy equivalent of a free lunch—they’re like a meal that users get paid for eating, to paraphrase energy guru Amory Lovins. They are so much cheaper to operate that they pay for themselves, and then some. They also are healthier and more pleasant places to live, work, and play.