Location: Ayer, Massachusetts

Watts: 7,700

Monthly Production: 710 kWh

Date: September 2018

These homeowners opted for very powerful, 350-watt solar panels to get as much electricity as possible from their solar energy system.

Over the system’s first 25 years, even taking into account what they paid for the solar, their electricity rate plunges from the $0.21 they’ve been paying National Grid, to just $0.06 with solar.