In a small town, every cent counts. The Berkshire Eagle reports officials in the town of Windsor don't like the way they're adding up after investing in a solar array.

They had hoped for help from Boston, but it didn't come in the Legislature's final hours this session.

Due to a wrinkle in state law, the relatively modest 20-kilowatt photovoltaic system Windsor installed with public funds this year behind its Route 9 town offices is classified as private. That wouldn't matter if all the electricity generated by three big ground-mounted panels is used inside town buildings.

However, Windsor counted on being able to send unused electricity out into the grid, earning credit that would dramatically cut its Eversource bill year-round.

After getting the system up and running, the town's Green Committee learned that under state law, the array's size classifies it as a private system, regardless of its public ownership. And because of net-metering caps that apply to Eversource and other utilities, the town cannot recoup the full retail value of the power it at times sends out through the utility's transmission lines.

Stu Besnoff, chairman of the Windsor Green Committee, calculates that instead of earning in the range of nearly 20 cents for every kilowatt hour of electricity the system produces, the town will get around 4 cents.

Over a year, the difference will amount to about $4,800, he said. The higher price is the retail one; the lower is wholesale.