Assessment
Reducing energy demand through energy efficiency measures such as weatherization and replacing fossil fuel equipment with heat pumps and other electric appliances remain the primary strategies to decarbonize the buildings sector. Heat pump installations are accelerating, with Mass Save installing roughly 18 percent more heat pumps year over year. With 90,384 households with heat pumps installed through Mass Save as primary home heating from January 1, 2021, through July 1, 2024, Massachusetts is on pace to exceed the 2025 target of 100,000 additional households with heat pumps as primary home heating between 2020 and 2025.[1] The number of home weatherization projects also increased, posting a gain of 18% in 2023 relative to 2022. In addition, 30% of the population now lives in communities that have adopted the specialized building energy code, a key lever for ensuring new construction and major renovations are highly efficient, resilient, and support grid-friendly electrification. Despite this progress, the annual rate of additional homes using heat pumps as a primary heating source will need to double between 2025 and 2030 to meet the target of 500,000 additional households with heat pumps from primary heating between 2020 and 2030. Further, efficiencies and electrification solutions will need to be scaled within the commercial and industrial sectors, which face challenges such as high capital costs and highly specific decarbonization applications. The Commonwealth will need additional interventions, including potentially new regulatory solutions, to accelerate decarbonization and achieve greenhouse gas emissions sublimits for the buildings sector.
| Metrics | 2023 Report Value | 2024 Report Value | Target |
|---|---|---|---|
| Number of households with heat pump installations[2] | 18,362 households installed heat pumps as their primary heating source in 2022 through Mass Save. 5,717 of those households installed heat pumps were full displacement of fossil fuel systems. 1,069 heat pumps were installed for income eligible households. As of the end of 2022, 34,769 households had installed heat pumps as their primary heating source since 2020 through Mass Save. [3] | 28,273 households installed heat pumps as their primary heating source in 2023 through Mass Save.[4] 12,296 of those households installed heat pumps were full displacement of fossil fuel systems. 2,592, heat pumps were installed for income eligible households. As of the end of 2023, 63,069 households had installed heat pumps as their primary heating source since 2020 through Mass Save. 27,315 households installed heat pumps as their primary heating source through Q3, 2024 through Mass Save. 10,266 of those households installed heat pumps were full displacement of fossil fuel systems. 2,758, heat pumps were installed for income eligible households. As of September 2024, 90,384 households had installed heat pumps as their primary heating source since 2020 through Mass Save. | The 2025/2030 CECP estimates heat pumps will be installed in at least 100,000 homes between 2020 and 2025 and at least 500,000 homes between 2020 and 2030. |
| Number of communities that have adopted the base, stretch, and specialized building energy codes.[5] | Base energy code: 8.5% of the population live in these municipalities (50 cities/towns) Stretch energy code: 66.6% of the population live in these municipalities (272 cities/towns) Specialized energy code: 24.8% of the population live in these municipalities (29 cities/towns) | Base energy code: 8.5% of the population live in these municipalities (50 cities/towns) Stretch energy code: 61.6% of the population live in these municipalities (253 cities/towns) Specialized energy code: 29.7% of the population live in these municipalities (48 cities/towns) | There is no current target for this metric, but increased numbers indicate progress toward highly efficient building envelopes in new construction which reduces impacts to our electric system. |
| Number of residential energy audits and weatherization projects[6] | There were 100,817 residential energy audits and 49,839 weatherization projects via Mass Save in 2022. 9,179 weatherization projects were for low-income participants.[7] | There were 117,131 residential energy audits and 59,877 weatherization projects via Mass Save in 2023. 11,865 weatherization projects were for low-income participants. | There is no current target for this metric, but increased numbers indicate reduced total energy use in buildings and may allow for smaller and less expensive heating electrification measures. |
[1] We are measuring meeting targets as the end of 2020 to the end of 2025.
[2] Current totals only include Mass Save installations. MLPs critical for decarbonizing the communities they serve but only support a small percentage of the total installations.
[3] The 2023 report card reported households with heat pumps through mid-2023. We revised the “2023 report value” to reflect the full 2022 reporting year and included 2023 and Q1-Q3 2024 on this report card to provide a more accurate tracking of changes from 2022 to 2023, and in order to provide the timely data for this quickly changing sector.
[4] During 2023 Municipal Light Plants also installed 1,919 heat pumps. Since some of these heat pumps may serve the same households, the numbers cannot be simply summed with the Mass Save households with heat pumps data.
[5] https://www.mass.gov/doc/building-energy-code-adoption-by-municipality/download
[6] Mass Save data
[7] Last year we reported that, “There were 89,970 residential energy audits and 40,446 weatherization projects in 2022. 9,179 weatherization projects were for low-income participants.” Our numbers this year differ because of updates to the 2022 Mass Save data.
Challenges
- Massachusetts’ residential buildings account for more than half of the state’s building emissions, and decarbonizing these buildings is complicated, costly, and requires a multi-pronged approach given the age and variety of structures.
- Mass adoption of decarbonization technologies such as heat pumps requires significant behavioral changes through a balance of engagement, customer incentives and regulatory interventions.
- Post-pandemic headwinds such as low occupancy rates and high capital costs have slowed commercial building owners’ adoption of decarbonization measures.
- Mass Save must deliver building decarbonization outcomes while also maintaining cost-effectiveness, minimizing ratepayer impacts and meeting equity objectives.
- Incentive-based programs require property owner cooperation, making it more challenging for renters to participate in and benefit from these programs.
- Residents increasingly need technical assistance to understand and navigate a growing number of state and federal incentive programs.
- Significantly increasing the pace of heat pump adoption will require considerable workforce training and re-training.
How we are meeting this moment
- Following a two-year investigation into the future of natural gas, the Department of Public Utilities (DPU) Order 20-80 set a new regulatory framework to guide the natural gas distribution industry evolution to clean energy. The DPU will prohibit cost recovery for gas infrastructure without proof that non-gas alternatives were considered or for promotion of natural gas expansion. Gas utilities must file Climate Compliance Plans every five years.
- The Energy Efficiency Advisory Council chaired by Department of Energy Resources (DOER) voted to support the 2025-2027 Mass Save Three Year Plan, which proposes significant equity investment and advances program improvements to support all customers in their decarbonization efforts. Highlights include reduction of 1 million metric tons of greenhouse gas emissions, over $1.9 billion to support equity outcomes, establishment of a statewide customer support center, programs to further support commercial and industrial decarbonization, and elimination of most incentives for fossil fuel equipment.
- The Interagency Rates Working Group (IRWG) issued a study and accompanying recommendations in December on near-term electric rate designs that prioritize reducing the costs of operating electric heat pumps. The IRWG will soon release additional recommendations with respect to long-term electric rate designs, which will focus on rate designs that can be implemented once advanced metering infrastructure is fully deployed in all utility service territories later this decade.
- Massachusetts actively pursued federal funds to advance building decarbonization. In July, EPA awarded $450 million to a coalition of states including Massachusetts to launch the New England Heat Pump Accelerator and leverage the regional market to rapidly accelerate adoption of cold-climate air-source heat pumps, heat pump water heaters, and ground source heat pumps in single-family and multifamily residential buildings. In September, the federal Department of Energy (DOE) approved DOER’s awards for Home Efficiency Rebates (HER) and Home Electrification Appliance Rebates (HEAR), for a combined formula allocation of $146 million. In October, DOER, in partnership with Massachusetts Clean Energy Center (MassCEC), Roxbury Community College, and Greenfield Community College, received a $2 million Energy Auditor Training grant. DOER, MassCEC, Boston, and Cambridge launched a new partnership, garnering a $19.9 million Assistance for Latest and Zero Building Energy Code Adoption grant from DOE.
- The Massachusetts Community Climate Bank launched the Energy Savers Home Loan in April 2024 to reduce energy use by at least 20% in 1 to 4-unit, owner-occupied homes owned by homeowners earning less than 135% of median income.
- MassCEC launched the Home Modernization Navigator in Springfield and Lowell in November 2024 to provide customized and ongoing guidance for underserved residents pursuing electrification, efficiency, and renewable energy projects. The program will expand in 2025 and is part of a statewide initiative led by the Executive Office of Energy and Environmental Affairs (EEA) Climate Team to make building decarbonization more accessible and equitable.
- In December, DOER released final regulations for Building Energy Reporting (BER), which requires the reporting of energy use data for buildings over 20,000 square feet. Reporting will formally start in 2025. BER complements work underway in Boston and Cambridge to implement building performance standards.
- The Department of Environmental Protection (DEP) continues to develop a Clean Heat Standard to drive fuel suppliers to replace fossil heat with clean heat. DEP is drafting regulations based on stakeholder feedback gathered throughout 2024.
- An additional 19 communities have adopted the specialized energy code since December 1, 2023, which requires performance-based Passive House standards to dramatically reduce energy use in new multifamily construction over 12,000 square feet and either full electrification of all space heating, water heating, cooking, and drying, or electrification-readiness wherever gas is used plus addition of rooftop solar.
- DOER awarded $26 million in its second round of grant funding to lower energy demand and decarbonize affordable housing properties, building on $27 million allocated via the program in 2023 and resulting in 1,313 decarbonized housing units in the first two rounds of funding. DOER intends to award its third round of grants, totaling $90 million in grant funding over the three rounds in spring 2025.
- In November 2024, MassCEC expanded its Building Electrification and Transformation Accelerator to establish replicable, lowest cost approaches for transitioning residential and commercial buildings from inefficient and fossil-fuel burning equipment to efficient, electric technologies.
- MassCEC sponsored an Inclusive Utility Investment (IUI) pilot with Ipswich Electric Light Department and the Center for Ecotechnology to demonstrate whether tariffed on-bill financing of decarbonization measures could remove barriers for low-income households, particularly renters, and decrease implementation costs.
- With support from the City of Framingham and the Commonwealth, Eversource launched the nation’s first utility-owned pilot networked geothermal system in June 2024. The one-mile loop is harnessing consistent underground temperatures to efficiently heat and cool 31 residential and five commercial buildings. Data collected from the pilot will enable replicable approaches for networked geothermal districts in Massachusetts and beyond.