Millis planning board recommends bylaw to define and zone battery storage and data centers

The Town of Millis Planning Board voted unanimously April 7 to recommend a proposed zoning bylaw amendment that would add definitions for "battery energy storage systems" and "data storage centers" and to limit larger facilities to industrial areas, forwarding the article to Town Meeting for consideration.

The board opened the 7:50 p.m. public hearing and discussed draft definitions prepared by the zoning bylaw review committee. Richard Nichols, chair of the Town of Millis Planning Board, said the committee aimed to give the town interim definitions because "these are 2 industries that are growing as the need for data storage grows and storage of solar energy or other energy source" and to provide locations that are suitable for Millis while state model bylaws are finalized.

The draft would categorize battery energy storage systems by aggregate energy capacity; the committee described "tier 1" systems as under 250 kilowatt‑hours (intended for homes and small business backup) and said larger tier 2 and tier 3 systems would be subject to location limits and generally permitted only in the industrial districts by special permit. A committee member cautioned that larger regional projects can be much bigger: "The Medway storage system is 500 megawatt hours. Mega megawatt hours, so it's actually 5 times the size of our maximum allowed according to these definitions," a committee member stated during the discussion.

During public comment, resident Peter Harkey urged the board to consider siting options that would reduce residential impacts, suggesting parcels near the hockey rink (Map 42, 47 and 46) and locations close to high‑tension lines. Harkey also raised practical concerns including flood‑zone changes, access roads and whether the town dump site could be used; board members replied that the landfill cap prevents digging there and that some IP2 industrial parcels (for example, where recent solar or industrial uses exist) may be more suitable.

Committee members and board staff noted practical constraints: large ground‑mounted solar installations and their associated storage are typically sited in industrial zones or on designated agricultural acreage, and the board said it may pursue an overlay district rather than rezoning individual parcels to avoid "spot zoning." The committee also said it will coordinate with Town Council and incorporate forthcoming state guidance into the town's final bylaw language.

At the meeting's close, the board took several procedural votes. The board voted to continue the separate Woodlands subdivision public hearing to May 12 at 7:30 p.m.; it approved minutes from the March 3 meeting; it closed the public hearing on the bylaw amendment; and it voted unanimously to recommend the proposed zoning bylaw article to Town Meeting. The board then adjourned.

The Planning Board's recommendation places the proposed definitions and use-table changes on the warrant for the next Town Meeting; further refinements — including any overlay district language, exact siting rules, and reliance on state model bylaws — will be developed before the article appears on the warrant.