The proposed bill, titled the "Building Decarbonization Act of 2025," aims to establish a building energy reporting program for covered properties. It introduces a new chapter in Title 23 of the General Laws, which includes definitions for key terms such as "benchmarking information," "covered property," and "energy." The Office of Energy Resources (OER) will oversee the program, requiring owners of covered properties—defined as buildings and campuses containing 25,000 or more gross square feet—to input their annual energy use and other relevant information into a benchmarking tool, such as the ENERGY STAR Portfolio Manager. The reporting schedule is set to begin in 2027, with specific deadlines based on the size of the buildings: properties with 50,000 or more gross square feet must report by May 15, 2027, and annually thereafter, while those with 25,000 to 49,999 gross square feet must report by May 15, 2029, and annually thereafter.

The bill outlines a notification process for property owners, requiring the OER to notify them of their obligations between September 15 and December 15 each year, starting in 2026. It also provides exemptions for certain conditions, such as if the property was unoccupied for the entire year or if a demolition permit was issued. Owners must provide benchmarking information to the OER annually, and the OER is required to publish a summary report on the program by October 15 each year.

Additionally, the bill allows municipalities that have initiated comparable building energy benchmarking requirements prior to the enactment of this chapter to continue their programs in lieu of the OER's requirements, provided they notify the OER within 180 days of enactment. The OER is tasked with developing incentives for participation in the program and may impose enforcement mechanisms, including escalating warnings and fines, starting in 2030. The act is set to take effect upon passage, promoting transparency and accountability in energy use and greenhouse gas emissions for large buildings.