SJC's Sunpin Decision: A Win For Solar Development, But Not The Last Word

On July 14, 2026, the Massachusetts Supreme Judicial Court (“SJC”) issued its decision in Sunpin Energy Services, LLC v. Zoning Board of Appeals of Petersham, holding in favor of solar development and reaffirming that local zoning boards have only narrow authority to deny solar special permits. While the decision should help deter denials based on obvious pretextual reasons, the absence of an objective standard may leave the door open for further disputes.

Under state law (G.L. c. 40A, § 3, ¶ 9), solar projects (and the storage projects that facilitate solar energy collection) are entitled to heightened protections from local zoning restrictions:

“No zoning ordinance or by-law shall prohibit or unreasonably regulate the installation of solar energy systems or the building of structures that facilitate the collection of solar energy, except where necessary to protect the public health, safety or welfare.”

The bounds of what municipalities can do to block solar development notwithstanding the limitations of ¶ 9 have been hotly contested for years. The SJC’s 2022 decision in Tracer Lane held that zoning bylaws that effectively banned solar development in most of a municipality were invalid. But it left unresolved the precise contours of when and how municipalities could prohibit or regulate solar facilities. Disputes have been frequent, and numerous lower court decisions have grappled with how to draw that line.

Sunpin’s case demonstrates how the legal uncertainties in this space are an obstacle for solar development in the Commonwealth. In April 2021, Sunpin applied for a special permit in Petersham. Although Sunpin’s project complied with the requirements in Petersham’s zoning bylaws for solar facilities, one of the members of the zoning board of appeals (“ZBA”) voted to deny the permit primarily because tree removal necessary for the project was contrary to her interpretation of the bylaw’s broader intent and purpose. With a three-member ZBA, that “no” vote meant a denial (since state law requires unanimity from three-member boards).

Sunpin challenged that decision in the Land Court, which upheld the ZBA’s denial. Sunpin appealed, and the Appeals Court reversed, holding that the ZBA had exceeded its discretion under G.L. c. 40A, § 3, ¶ 9. Petersham appealed to the SJC, and now—more than five years after Sunpin applied for its special permit—we have a decision in favor of Sunpin that sends the case back to the ZBA for further consideration. A five-plus year legal detour is not a light burden.

The SJC’s decision sets out a new standard for assessing whether a municipality has acted within its authority to deny a special permit for a solar facility. Like the Appeals Court, the SJC rejected the high degree of deference to local boards that the Land Court had relied upon.

The SJC’s new standard eliminates many of the grounds that municipalities previously asserted when denying special permits for solar facilities. First, the SJC expressly reaffirmed that the Legislature intended that towns “should support and not unduly interfere” with the siting of solar projects. Second, the SJC reiterated that “a town must provide reasonable opportunities to build solar energy systems and may not deny a special permit for such a project unless doing so is necessary to protect public health, safety, or welfare.” Third, the SJC held that G.L. c. 40A, § 3, ¶ 9 “affords municipalities only a ‘narrow ambit’ within which they may properly deny a special permit for [a] solar energy system.”

The controlling standard going forward appears to be “whether the denial of the special permit is necessary to protect the public health, safety, or welfare at [the facility’s] particular location as provided by paragraph nine or reflective of a general prohibition or unreasonable regulation of solar energy systems that is precluded by the rest of paragraph nine.” (emphasis added).

As applied in this case, the SJC annulled Petersham’s denial of the special permit, which was largely based on general concerns about the effects of tree removal. The Court found that allowing Petersham to use tree removal as a basis for denying a solar special permit, where the town is 97% forested, would effectively allow a blanket prohibition against solar that is not “necessary” to protect public health, safety, or welfare.

Of particular note, Petersham had also argued that its denial was consistent with the general purpose clause in its zoning bylaw, under which the bylaw is to “promote the health, safety and general welfare.” The SJC rejected the town’s assertion that this general purpose clause was sufficient to deny the solar special permit. The SJC specifically noted that “what is ‘necessary to protect’” public health, safety, or welfare is more narrow and limited than what may be deemed to “‘promote’” those interests.

The new standard is unlikely to eliminate continued disputes. A legal standard on point from the SJC should improve clarity for municipalities and developers. The SJC’s decision clearly envisions a material restriction on municipal authority—establishing only a “narrow ambit” within which to act. But, as we saw with Tracer Lane, a subjective reasonableness standard likely lacks the level of precision that would effectively deter municipal overreach and avert continued disputes. Whether the restrictions imposed in a particular bylaw “provide reasonable opportunities to build solar energy systems,” whether reasons for denial fall within the SJC’s “narrow ambit,” and whether such reasons are focused on the particular location of a facility (as opposed to general sentiments) may well become new framings for familiar arguments.

Following Sunpin, solar developers can put themselves in a stronger permitting position by developing a clear record that their projects do not threaten public health, safety, or welfare at the site-specific proposed location. Developers should also track a given municipality’s pattern of large-scale solar approvals and denials, since under Sunpin it appears that a town's cumulative practices can itself become evidence of a de facto blanket prohibition.

Under Sunpin, developers facing a special permit denial premised on generic preferences against tree-cutting or "community character" concerns now have a much stronger basis to challenge such denials. But the procedural trajectory of Sunpin also demonstrates the ability of local authorities to delay and frustrate solar development. The Sunpin decision is a step in the right direction, but only time will tell whether it is clear enough to prevent continued local obstruction of environmentally sound solar projects.