WHO: Doug Hanna

WHERE: Cambridge

Hanna, 54, is the tall, gentlemanly "H" of S + H Construction, a Cambridge-based residential contracting company. Worried about the cost of energy, he was encouraged by eco-conscious clients to pursue solar panels for his own home. Last year, Hanna bought 22 eight-square-foot, 175-watt panels to create 176 square feet of solar surface-enough to power his home and then some. Now his energy provider pays him, for the surplus electricity he sends back into the grid. Hanna's roof, which is 20 degrees west of due south, had to be reinforced to support the extra weight of the panels. Luckily, he happened to know a good contractor for the job.

The Setup

the balance sheet