GRAY – Ecology students at Gray-New Gloucester High School on Friday showed the public 16 rooftop solar panels and the electric-generating power system they helped develop to cut energy costs.

Eighteen juniors and seniors in Peter Reaman’s class led the tour, which began outdoors on a cold, cloudy day. It was the culmination of an idea by Reaman to apply for an alternative energy grant from the Voluntary Renewable Resources Fund. The school was awarded $36,450 through a state program administered by the Maine Public Utilities Commission.

Reaman decided on the solar project after looking at the large metal roof that faces south.

“This is a service learning project,” he said. It serves the school and teaches students at the same time.

The panels, which cost $1,200 each, collect heat from the sun and conduct electrons that travel through wires into the school. A former janitor’s closet is outfitted with a $2,600 inverter that generates direct current, which is converted to alternate current for the school, students said.

A $1,400 computer system communicates to a Web site and measures the amount of electricity generated. If there’s more than the school needs, it gets credit from Central Maine Power Co., they said.

In Reaman’s classroom, students showed the technical monitoring system. Senior Brittney Norton, 17, took the helm of the computer to show the day to day and week to week electrical production.

Public displays and lesson plans will be developed for different age levels as part of the project’s mission.