Across the United States, zoning is highly inconsistent, even within the same state. Fewer than 15 states have implemented model bylaws, ordinances, or zoning guidelines to assist their municipalities with zoning specifically for solar projects. In October 2025, the Massachusetts Department of Energy Resources (DOER) issued the Model Zoning Bylaw: Allowing Use of Solar Photovoltaic Installations (“Model Bylaws”).1 The Model Bylaws are meant to provide a framework and guidance for municipalities to use when developing their own solar zoning regulations.2 Although adoption of the Model Bylaws by municipalities is not mandatory, it will likely have a heavy influence in 2026 on the zoning regulations that the municipalities do enact. For that reason, the Model Bylaws serve as a potential win for developers and investors of solar infrastructure by providing consistency in zoning bylaws for municipalities that want to align with DOER’s expectations.
Consistency with other MA Law
The Model Bylaws are consistent with Massachusetts General Laws chapter 40A, § 3, which prohibits municipalities from enacting unreasonable regulation on solar energy (also known as the “Dover Amendment”). Massachusetts General Laws chapter 25A § 21(b) further states that local governments that implement the DOER standards for siting and permitting small clean energy infrastructure “shall be considered to have acted consistent with the limitations on solar facility and small clean energy storage facility zoning under the [Dover Amendment]..” The Model Bylaws also align with An Act Promoting a Clean Energy Grid, Advancing Equity and Protecting Ratepayers (“2024 Climate Act”) and other agency regulations originating from the 2024 Climate Act.3 The Model Bylaws’ consistency with state law will likely encourage municipalities to adopt them with only minor adjustments. However, it is important to note that the Model Bylaws must be supplemented by other applicable regulations, such as the State Fire Code (527 CMR 1.00) or the Massachusetts State Building Code (780 CMR); developers and investors cannot, therefore, look only to the Model Bylaws as a panacea for other zoning complications.
Predictability in the Permitting Process
The Model Bylaws are developer-friendly in many ways. One such way is the emphasis on predictability in the permitting process. The Model Bylaws use defined categories and distinguish between system sizes to determine whether solar installations are permitted By Right (“subject to a building permit only”), By Right Subject to Site Plan Review (“the Site Plan Review authority may not unconditionally deny the Site Plan Applications, but rather, it may impose reasonable conditions upon them”), with a Special Permit required, or are Not Permitted. Smaller, building-mounted, or accessory systems generally fall into the By Right category, while larger, ground-mounted systems are subject to extra review, giving them By Right Subject to Site Plan Review or Special Permit status. However, under the 2024 Climate Act, municipalities are only required to oversee the permitting process for “small systems,” those that are under 25 megawatts.4 Large scale systems (larger than 25 megawatts) fall under the purview of the Energy Facilities Siting Board and are not covered in the Model Bylaws.
The Model Bylaws invite municipalities and local governments to rely on these objective standards, which will remove uncertainty and delays that have discouraged past development inconsistent with Massachusetts’ push for an increase in development of renewable energy infrastructure (which have created confusion and frustration for many Massachusetts developers in the past). If the Model Bylaws are adopted by municipalities across the state, it also creates a sense of uniformity for developers. Developers should engage with zoning analysis early and determine whether the specific municipality conforms to the size standards in the Model Bylaws.
Dimension Requirements and Design Standards
The Model Bylaws also address dimension requirements as well as design standards for setbacks, screening, access, signage, lighting, and fencing. These standards are framed as generally applicable land use controls, rather than requirements that are unique to solar projects. For setbacks specifically, the Model Bylaws include the recommendation that municipalities should apply the same setbacks to solar developments as they do to similarly situated project types. This provides developers with more comfort, particularly in a state where many developers must appeal decisions in court to challenge solar-specific restrictions.
Decommissioning and Site Restoration
Decommissioning and site restoration are also discussed in detail, mandating that developers remove their systems at the end of their useful life, dispose of all solid and hazardous waste, and stabilize or re-vegetate the site as necessary to minimize erosion. Additionally, the Model Bylaws outline rules for decommissioning funds, requiring that a project owner provides surety in the amount of 125% of the fully inclusive estimate of the costs associated with removal. This fund may also be accessed if a project owner abandons the solar system. While the 125% surety may seem like a steep cost to developers and project owners, the flat percentage may benefit developers by limiting excessive municipal demands. The Model Bylaws also call for updating the decommissioning estimate after the first 10 years and again every 5 years thereafter, which is consistent with the practices followed in many Massachusetts municipalities currently. Regardless, the surety is something that developers and project owners should consider early in the development process.
Conclusion
The Model Bylaws provide insight into DOER’s expectations when it comes to zoning small and medium size solar projects. Developers and project owners who operate in municipalities that have adopted bylaws in line with the Model Bylaws should have a more predictable development process, including addressing zoning, engaging with municipal officials, and even challenging local barriers to development that are inconsistent with Massachusetts state law. The release of the Model Bylaws is occurring alongside other changes in solar development as well, such as the model zoning bylaws for battery energy storage systems (BESS).5 As Massachusetts continues to aggressively pursue its goal of zero emissions by 2050, the Model Bylaws are sure to play an influential role in the local regulatory landscape in 2026 and beyond.
1 Model Zoning Bylaw: Solar
2 Clean Energy Siting & Permitting FAQ, Mass.gov https://www.mass.gov/info-details/clean-energy-siting-permitting-faq.
3 One such regulation is the DOER draft standards for siting and permitting for small clean energy infrastructure, which are set to be finalized on February 13th, 2026. (225 CMR 29: 225 CMR 29.00: Small Clean Energy Infrastructure Facility Siting And Permitting Draft Regulation | Mass.gov)
4 Session Law - Acts of 2024 Chapter 239
5 Draft Model Bylaw: BESS
[View source.]
