Solar Array Slashes Mill Pond's Electric Bill

Burlington's Mill Pond water treatment plant has a new energy-saving feature that has been benefitting the town's electric bill for the last several months.

A solar array was installed on the roof of the building in 2024 and began operation last November. Subsidized almost entirely by the Massachusetts Department of Environmental Protection (MassDEP)'s Gap Energy Grant, the $200,000 solar panel and weatherization project was intended to reduce energy costs to the town.

The array, which cost the town less than $20,000 after the grant and energy incentives were applied, is expected to produce around 87,000 killowatt-hours (kWh) of energy and save the town more than $18,000 annually on electric bills, offsetting the expense to run the water treatment plan and resulting in a payback of just about a year.

By generating its own electricity, the facility, which now includes a new PFAS removal system, can decrease its dependence on the grid and cut operating costs.

This project is separate from the town’s municipal aggregation program – which enables lower electricity rates for residents and businesses – but similarly reflects an effort to manage resources more efficiently at a time when several building projects are expected to significantly impact taxes.