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HOUSE DOCKET, NO. 4121 FILED ON: 1/17/2025
HOUSE . . . . . . . . . . . . . . . No. 3467
The Commonwealth of Massachusetts
_________________
PRESENTED BY:
Mike Connolly
_________________
To the Honorable Senate and House of Representatives of the Commonwealth of Massachusetts in General
Court assembled:
The undersigned legislators and/or citizens respectfully petition for the adoption of the accompanying bill:
An Act establishing solar neighborhoods.
_______________
PETITION OF:
NAME:DISTRICT/ADDRESS :DATE ADDED:Mike Connolly26th Middlesex1/17/2025 1 of 4
HOUSE DOCKET, NO. 4121 FILED ON: 1/17/2025
HOUSE . . . . . . . . . . . . . . . No. 3467
By Representative Connolly of Cambridge, a petition (accompanied by bill, House, No. 3467) of
Mike Connolly relative to establishing solar neighborhoods. Telecommunications, Utilities and
Energy.
[SIMILAR MATTER FILED IN PREVIOUS SESSION
SEE HOUSE, NO. 3677 OF 2023-2024.]
The Commonwealth of Massachusetts
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In the One Hundred and Ninety-Fourth General Court
(2025-2026)
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An Act establishing solar neighborhoods.
Be it enacted by the Senate and House of Representatives in General Court assembled, and by the authority
of the same, as follows:
1 Chapter 25A of the General Laws, as appearing in the 2022 Official Edition, is hereby
2amended by inserting after section 18 the following section:-
3 Section 19. Solar neighborhoods act.
4 (a) As used in this section the following words shall have the following meanings unless
5the context clearly requires otherwise:-
6 “Battery storage system,” a system allowing electricity to be stored in and discharged
7from batteries.
8 “Developer”, any person or company that constructs residential or commercial buildings. 2 of 4
9 “Green roof,” a layer of vegetation planted over the roof of a building.
10 “Multi-family dwelling”, a building intended to be inhabited as a primary or secondary
11residence by multiple individuals or groups of individuals living in separate apartments.
12 “New building”, any newly constructed residential or commercial building that requires a
13building permit to proceed.
14 “Single-family dwelling”, a building intended to be inhabited as a primary or secondary
15residence by one individual or group of individuals.
16 “Solar energy system”, any solar photovoltaic system that is installed on site and uses
17solar energy to provide all or a portion of the electrical needs of a residential or commercial
18building.
19 “Solar hot water heater”, any system that uses solar energy to heat water for use in a
20residential or commercial building.
21 “Substitute renewable energy system”, a renewable energy generating source, as defined
22in section 11F of chapter 25A, that is not a solar photovoltaic system, is installed on site, and
23provides all or a portion of the electrical needs of a residential or commercial building.
24 (b) The department, in consultation with the state board of building regulations and
25standards, shall develop and promulgate amendments to the base energy code, stretch energy
26code, and specialized stretch energy code established under section 6 of chapter 25A and
27sections 93 through 100 of chapter 143 requiring new buildings to be built with solar energy
28systems. 3 of 4
29 (c) Detached one- and two-family dwellings and multiple single-family dwellings or
30townhouses regulated under the provisions of the residential code shall have a solar energy
31system producing sufficient electricity on an annual basis to meet at least 80 percent of the
32estimated average annual electricity use of dwellings of a similar size. The department may
33reduce the required minimum generating capacity of solar energy systems for these dwellings by
34up to 25 percent if installed in conjunction with a battery storage system with a minimum
35capacity of 7.5 kilowatt-hours per dwelling unit.
36 (d) Multi-family dwellings and commercial buildings up to six stories in height shall have
37a solar energy system and battery storage system of a minimum capacity established by the
38department, which may be based on the size of the roof and effective solar area, building type
39and occupancy, estimated average annual electricity use of similar buildings, or other factors.
40 (e) The department may require other categories of new buildings to have a solar energy
41system or battery storage system, and set requirements for the minimum generating capacity of
42the solar energy system installed on those buildings.
43 (f) The department shall estimate the average annual electricity use for the categories of
44buildings described in this section and revise its determination at least every three years, taking
45into account changes in electricity use due to energy efficiency improvements, electric vehicle
46charging, electric heating and cooling technologies, and other factors.
47 (g) In promulgating these regulations, the department may include provisions to ensure
48that new buildings can accommodate solar energy systems on their rooftops, including but not
49limited to requirements for static load roof strength, placement of rooftop equipment, sizing and
50provision of extra electrical panels, provision of space for a solar energy system DC-AC inverter 4 of 4
51in the utility room or on an outside wall, roof orientation and angle, roof types that are
52compatible with a solar installation mounting strategy that will require minimal or no roof
53penetrations, and conduits for wiring from roofs to electric panels.
54 (h) The department shall establish criteria under which developers can seek an exemption
55from the requirements of this section. Such criteria may include insufficient rooftop solar energy
56generating potential, the installation of a substitute renewable energy system or solar hot water
57heater at the time of construction, the installation of a solar energy system over a parking lot or
58elsewhere on the property, and participation in a community solar project. The department may
59allow exemptions from the requirements of this section for affordable housing developments,
60after consulting with affordable housing developers and operators, community development
61corporations, organizations that represent affordable housing residents, and other stakeholders.
62 (i) The provisions of the building code adopted under this section shall allow the
63installation of a green roof in conjunction with a rooftop solar energy system.
64 (j) A building permit for a new building shall not be granted without a showing that the
65building complies with the requirements of this section.
66 (k) Any person who fails to comply with or otherwise violates this section shall be liable
67for a civil administrative penalty not to exceed $10,000 for each violation, or twice the estimated
68additional cost that would have been incurred by constructing a building to meet the
69requirements of this chapter, whichever is greater.
70 (l) The department shall promulgate regulations within 1 year of the passage of this act to
71enforce this section. All future editions of the base energy code, stretch energy code, and
72specialized stretch energy code shall include provisions meeting the requirements of this section.