Solar Energy Policy History in Massachusetts: Key Legislation and Program Milestones

Massachusetts has assembled one of the most layered solar energy policy frameworks in the United States, built through successive legislative acts, regulatory rulemakings, and program restructurings spanning more than two decades. This page traces the key legislation, incentive programs, and administrative milestones that define how solar energy is governed in the Commonwealth. Understanding this policy history is essential context for property owners, developers, and researchers evaluating how current rules, incentives, and utility obligations came to exist. The Massachusetts Solar Authority home resource situates this history within the full operational landscape of solar deployment in the state.

Definition and scope

Solar energy policy in Massachusetts refers to the body of statutes, regulations, administrative programs, and utility obligations established by the Commonwealth that govern the installation, compensation, interconnection, and incentivization of solar photovoltaic (PV) systems. This framework is not a single law but an evolving stack of instruments: renewable portfolio standards, net metering statutes, solar carve-outs, incentive programs administered by the Massachusetts Clean Energy Center (MassCEC), and utility tariffs approved by the Department of Public Utilities (DPU).

Scope and coverage: This page addresses solar-specific policy history within Massachusetts state jurisdiction. Federal instruments — including the federal Investment Tax Credit (ITC) authorized under 26 U.S.C. § 48 — operate in parallel but are not administered by the Commonwealth. Interstate policies, New England grid-level rules managed by ISO New England, and offshore wind policy are adjacent topics not covered here. Local zoning regulations enacted by the 351 individual municipalities in Massachusetts are also outside the scope of this historical overview, though they interact with state-level frameworks.

For a structured examination of how current rules fit together, see Regulatory Context for Massachusetts Solar Energy Systems.

How it works

Massachusetts solar policy operates through four primary mechanisms that interact: (1) a Renewable Portfolio Standard (RPS) that creates market demand, (2) net metering rules that determine how surplus generation is compensated, (3) incentive programs that provide direct payments or certificates, and (4) interconnection requirements that govern how systems connect to the grid.

Key legislative and program milestones — chronological breakdown

1. 1997 — Utility deregulation and RPS establishment. The Electric Restructuring Act (M.G.L. c. 164, § 11F) restructured the electric industry and created the initial Renewable Portfolio Standard, requiring a percentage of electricity sales to come from eligible renewable sources.
2. 2002 — Solar carve-out concept introduced. The Department of Energy Resources (DOER) began incorporating solar-specific requirements into RPS compliance structures, distinguishing solar's higher cost profile from wind and other renewables.
3. 2008 — Green Communities Act. M.G.L. c. 169 dramatically expanded the RPS annual increase requirement to 1% per year, extended net metering eligibility, and established the framework that eventually produced the Solar Carve-Out program. The Act directed DOER to create a Solar Carve-Out (SCI) within the RPS Class I category.
4. 2010 — Solar Carve-Out I (SCI) launch. DOER launched the Solar Carve-Out program, requiring distribution companies to source a rising percentage of electricity from solar PV. Compliance was demonstrated through Massachusetts Solar Renewable Energy Certificates (SRECs), each representing 1 MWh of solar generation.
5. 2014 — Solar Carve-Out II (SCII). As SCI neared its capacity ceiling of approximately 400 MW (DOER SREC II Program documentation), DOER launched SCII with a modified SREC pricing mechanism designed to stabilize revenues for project developers while controlling ratepayer costs.
6. 2016 — An Act Relative to Solar Energy (H. 4868). This legislation raised the net metering cap for private systems from 3% to 8% of a distribution company's peak load and directed DOER and the DPU to design a successor incentive program to SRECs.
7. 2018 — SMART Program launch. The Solar Massachusetts Renewable Target (SMART) program replaced the SREC structure with a fixed declining-block incentive paid in dollars per kilowatt-hour. The SMART program, administered by DOER and the three investor-owned utilities — Eversource, National Grid, and Unitil — established 200 MW blocks across multiple utility territories.
8. 2021 — Climate Act (S. 9). An Act Creating a Next-Generation Roadmap for Massachusetts Climate Policy set a binding net-zero emissions target by 2050, raised the RPS annual increase to 2% per year starting in 2025, and required DOER to set interim 2025 and 2030 clean energy targets.
9. 2022 — SMART expansion. DOER authorized expansion of the SMART program to 3,200 MW total capacity statewide (DOER SMART Program), more than tripling the original 1,600 MW authorization.

For a conceptual explanation of how these mechanisms interact in practice, see How Massachusetts Solar Energy Systems Works.

Common scenarios

SREC I vs. SREC II vs. SMART — generational comparison

Systems installed before 2014 may still hold SREC I eligibility with a Sustainable Development Adder. Systems entering between 2014 and 2018 fall under SCII with market-indexed pricing. Systems installed after SMART's launch receive a fixed $/kWh adder declining across capacity blocks — a fundamentally different risk profile from the SREC market. A system owner under SREC I faced price volatility tied to SREC market supply; a SMART participant receives a contracted rate for 10 years, eliminating market price exposure.

Net metering cap transitions: Prior to the 2016 Act, distribution companies including Eversource had reached the 3% net metering cap, halting new applications in portions of their service territory. The cap increase to 8% reopened interconnection queues and directly enabled mid-sized commercial projects that had been stalled.

Municipal and community projects: The 2008 Green Communities Act and subsequent legislation created pathways for municipal solar projects and community shared solar, with SMART establishing specific capacity blocks and adders for these project categories.

Decision boundaries

Policy generation determines which program rules apply to a specific system. The classification boundaries are structural, not discretionary:

• SREC I eligibility: System must have received a Statement of Qualification from DOER before the SCII program launch date. Late qualification applications are not accepted retroactively.
• SCII eligibility: Qualification required before April 25, 2018, the SMART program effective date.
• SMART eligibility: Requires an approved interconnection application with a SMART-participating utility and a reservation within an open capacity block. Once all blocks in a utility territory are filled, new systems must await additional block authorization.
• Net metering vs. SMART compensation: These are not mutually exclusive — a system can receive both net metering credits and SMART incentive payments, but the interaction between the two is governed by specific DPU tariff rules that differ by utility.

The Massachusetts Clean Energy Center, DOER, and DPU each maintain distinct jurisdictional roles: MassCEC administers financing and rebate programs, DOER manages RPS and SMART program rules, and DPU approves utility tariffs and interconnection standards. Understanding which agency controls which program element is essential for navigating compliance, appeals, or program modifications.