Planning board urges narrow interim limits on large battery storage as state fast‑tracks siting

Nicole Riley, chair of the Zoning Bylaw Review Committee and a Planning Board member, told the Millis Finance Committee on April 15 that Article 17 is intended as a first step to add definitions and two columns to the use table so battery energy storage systems are placed where the town can manage them. "Battery energy storage systems are a new big plug for the state of Massachusetts" she said, adding the state has created a streamlined permitting pathway that could otherwise allow siting in places the town does not want.

Why it matters: Riley said the state adopts tiered definitions (tier 1, 2 and 3) based on size. She and the Planning Board recommend allowing tier 1 — household or rooftop‑scale systems — broadly while restricting larger tier‑2 and tier‑3 systems to the town's industrial zones by special permit. "If you don't zone it somewhere, the industry can go anywhere," she said, arguing the interim change protects neighborhoods while the town works with the energy committee and town council on a fuller bylaw to return in the fall.

Key details: Riley described tier 1 as generally under about 250 kilowatt‑hours — "a storage system that would be about 8 by 10 ft." — and noted those systems are similar to rooftop solar backups and would follow building‑permit processes rather than planning board special permits. For larger facilities she said the Planning Board intends to use special permits in the industrial and industrial‑2 zones as a temporary measure so the town is not forced to litigate under state rules. She also raised the possibility of an overlay district for locations along high‑tension lines near the ice rink if those sites prove appropriate.

Safety and other concerns: Committee members raised fire and safety questions and asked whether towns nearby had used moratoria on data centers or storage facilities. Riley noted some Massachusetts towns have one‑year moratoria for large data centers but said she doubted a moratorium would pass Attorney General review in this case; instead the Planning Board is proposing targeted zoning language. She also flagged data centers separately, saying they "utilize an outrageous amount of electricity and an outrageous amount of water" and have in some places contributed to local service stress.

Next steps and committee action: Riley described Article 17 as an interim, protective step so the town is not left without zoning in light of state fast‑track permitting. The Finance Committee asked questions about tiers, permitting pathways and possible overlay districts; the committee later voted to recommend approval of Article 17 as written. The Planning Board and energy committee will continue to develop a fuller bylaw for a future town meeting.

What remains unclear: Committee members asked about exact local capacities in Millis and whether other towns use four tiers; Riley said she would look into local examples and noted some towns have different tier structures. The definition and interim limits in Article 17 rely on the Department of Energy Resources' (DOER) tier definitions and on Attorney General approval of any bylaw change.

The committee is scheduled to bring Article 17 to the May 2026 Town Meeting with a recommendation to approve.