MIT Sustainable Design Lab and the Commonwealth of Massachusetts Launch New Collaboration on Home Energy Efficiency

A new collaboration between the MIT Sustainable Design Lab and the Commonwealth of Massachusetts aims to help reduce greenhouse gas emissions generated by homes, facilitate the state’s smooth transition to clean energy—and save homeowners money.

Christoph Reinhart, the Alan and Teri Spoon Professor of Architecture and Climate at MIT and head of the Sustainable Design Lab, explained that the research team has built a model of approximately 2.5 million existing residential buildings in Massachusetts. Drawing upon available data, the model can help the state make targeted policy choices to meet the greenhouse gas emission limits outlined in the Massachusetts Clean Energy and Climate Plan. For example, policymakers could use the model to identify neighborhoods with the most potential cost and emissions savings; state programs could then target outreach or incentives to assist those residents in reducing their energy costs and emissions. 

In addition, an accompanying public web app called the Massachusetts Building Inventory allows individual Massachusetts homeowners to look up their homes, provide some information about the building’s energy-related features, and then learn about which energy-efficiency investments in their home are likely to result in the quickest payback or have the biggest impact on the building’s CO₂ emissions. 

The hope is that clear guidance about what projects are most impactful will help accelerate individual homeowners’ investments to enhance their homes’ energy efficiency. “Providing clear, actionable and customized information to owners is expected to increase awareness and trigger owners into action,” Reinhart observed.

"We are excited to partner with MIT and harness their expertise to make Massachusetts more affordable and address some of our toughest climate challenges,” said Katherine Antos, Undersecretary for Decarbonization and Resilience at the Massachusetts Executive Office of Energy and Environmental Affairs. “This collaboration will model residential buildings statewide, informing state strategies to save energy and reduce emissions and empowering homeowners and renters alike to control their energy use, take full advantage of rebates, and lower their bills. We're looking forward to advancing innovative new ideas through this collaboration." 

According to Reinhart, this project employs a new simulation technique called “semantic building energy modeling” (SBEM) that leverages large data sets about buildings—containing information such as square footage and year of construction—to estimate the current energy use of a given residential area. To account for unknown quantities, such as whether the attic of a building is occupied and insulated, or whether the owner has installed LED lighting throughout the home, the physics-based model produces a range of estimated annual utility costs and greenhouse gas emissions for each building. Then, visualizations based on the aggregated energy use data can offer policymakers insights into what kind of building retrofits are needed to help meet a region’s greenhouse gas emission reduction goals and lower energy bills.

In the past, the Sustainable Design Lab has worked with policymakers in over 20 cities, including Dublin and Cairo, using earlier iterations of the building energy modeling approach. This is the first time the team has modeled a region as large as an entire U.S. state, and Reinhart hopes it won’t be the last such project. He envisions expanding to model other states’ housing stock, perhaps eventually creating a nationwide database and expanding to other countries, too. 

However, Reinhart stressed that an important question for him when considering any such project is: “Is there a policymaker at the table?” 

Having a committed policymaker partner is key for the kind of real-world impact that Reinhart, who heads up the MIT Climate Project’s mission on resilient cities and is also an affiliated faculty member of the MIT Climate Policy Center, strives for. “I am not interested in just doing this as an academic exercise,” he said. 

Reinhart’s emphasis on working closely with policymakers is an excellent example of the MIT Climate Policy Center’s approach, said Bethany Patten, the Center’s Executive Director.  “This kind of collaboration exemplifies why MIT launched the Climate Policy Center in 2024,” she said. “The best tool we can offer policymakers hoping to devise practical, effective solutions to climate- and energy-related issues is impartial, evidence-based, and robust data.”

The Climate Project at MIT is a whole-of-MIT initiative to respond to the multiple challenges of global climate change. Through this strategic initiative, announced by MIT President Sally Kornbluth in 2024, MIT seeks to become, within a decade, one of the world’s most prolific and collaborative sources of technological, behavioral, and policy solutions that will change the expected trajectory of global climate outcomes for the better.