Path 2: Whole Building Energy Use Intensity (EUI) Reduction Approach (50,000 sf or greater)

Whole Building EUI Hero
Path 2 Whole Building Energy Use Intensity (EUI) Reduction Approach provides building owners and design teams with energy efficiency expertise early in the design process. EUI is like a building's "miles per gallon" metric. The lower the EUI, the more efficient the building. It is a simple way of understanding your building's energy use, and how it compares to other buildings or itself over time.

Your team will receive technical assistance to establish and design toward an EUI target, as well as financial incentives to install equipment and systems that will enable the project to meet the target. Projects are eligible for significant incentive adders when they include cold climate heat pumps.
Path 2: EUI Reduction Incentive Tiers
% Reduction Required to Participate


Incentive Rate Space Heating Heat Pump Adder All sectors other than office/labs Office Lab/office
Tier 4 $0.35/sf Air source Heat Pumps: $800/ton
Variable Refrigerant Flow (VRF): $1200/ton
Ground Source Heat Pumps: $4500/ton
10%-15% 5%-10% 15%-20%
Tier 3 $0.50/sf 15%-20% 10%-15% 20%-25%
Tier 2 $0.75/sf 20%-25% 15%-20% 25%-30%
Tier 1 $1.25/sf 25% and above 20% and above 30% and above

For more details on this path, please click here.

Download the Memorandum of Understanding for Path 2 Whole Building EUI Reduction Approach for a full description of the process and requirements for this program.  

To be eligible, the project team must be willing to establish a target EUI. The project will receive incentives according to percent EUI reduction beyond the Mass Save baseline EUI - EUI percent reductions that determine incentives are calculated based on the project's final design and paid at the end of construction if the building is built as designed. Target EUIs must be anticipated to meet minimum percent reductions per sectors as outlined on the Incentives tab.

Site Energy Use Intensity (EUI): a measure of a building's gross annual site energy consumption (including all fuels) relative to its gross square footage. The units are kBtu/sf/year.

For this Program, gross square footage excludes parking garages and penthouse square footage, as these are not typically conditioned spaces. The Program's EUI calculation does not include onsite renewables.

In alignment with the Commonwealth's policy and climate goals, the Sponsors of Mass Save are discontinuing incentives for fossil fuel equipment and new construction buildings that utilize fossil fuel equipment. Effective January 1, 2025, the Sponsors of Mass Save will no longer be permitted to issue incentive payments tied to fossil fuel equipment or new construction buildings with fossil fuel equipment.

For new projects enrolling, view the C&I New Buildings and Major Renovations Participation Requirements to distinguish eligibility of new construction vs. major renovation buildings.