Location: Westborough, Massachusetts

Watts: 11,725

Monthly Production: 1008 kWh

Date: January 2016

The homeowners of this Colonial-style house received about $22,000 off the price of their solar energy system, thanks to state and federal tax credits. Between tax credits, “SREC” income and electricity savings, solar is a better bargain than ever. The system was installed on two roofs, as the early schematic drawing shows.