Amy Norquist
Greensulate, New York City

Amy Norquist was a rising star of the environmental nonprofit world, having toiled at half a dozen nonprofits, each with the word earth in its name, and having become, in 2003, deputy director at the Beacon Institute for Rivers and Estuaries in New York.

Then, in 2007, she tried to install a green roof on her home in Shelter Island, New York. "This is just hellish," she thought. "Other people shouldn't have to go through this." And now they don't.

Norquist left Beacon, woodshedded for six months, and emerged with a plan for Greensulate, now a $1.2 million company that has insulated 100,000 square feet of rooftop with gorgeous meadows of lavender, native grasses, and a hardy succulent called sedum. The effort has eliminated 3,300 pounds of carbon from the atmosphere.

Greensulate is expanding at 400 percent a year, but Norquist, 47, remains a humble, no-nonsense sort whose 13-person team operates out of a Manhattan co-working space the size of a walk-in closet. "I've found the for-profit model so much simpler," Norquist says. "The harder we work, the better we do. Simple."