The current version of the MEPA GHG Emission Policy and Protocol (GHG Policy) is dated May 5, 2010.

If you have questions regarding the GHG Policy, or to set up a pre-filing meeting, please contact with Josie Wixon at 617-626-1031 or

The following material is provided for informational purposes and is not intended to supersede specific directives included in Certificates issued by the Secretary or Energy and Environmental Affairs or guidance provided in pre-filing meetings between a project proponent and the MEPA office.

Distribution of MEPA Filings subject to the GHG Policy

For projects that are subject to the GHG Policy, in addition to the filing and circulation requirements as noted at 301 CMR 11.16, copies of all MEPA submissions should be sent to:

Department of Energy Resources
Attention: John Ballam
100 Cambridge Street, Suite 1020
Boston, MA  02114

Department of Environmental Protection
Attention: Christine Kirby
One Winter Street
Boston, MA  02114

Submissions to DOER and DEP should include text file output data that list the input and default modeling parameters generated by the selected modeling software, program generated reports, or tabulation of all the input and default values necessary to verify modeling conclusions. Summaries of these data should be provided in narrative/tabular format in the filing, with supporting data provided on CD-ROM or flash drive if necessary to save paper resources.

State Agency Resources

State Agency websites have a wealth of information of State energy efficiency and renewable energy initiatives:

Department of Energy Resources:

Department of Environmental Protection:

Global Warming Solutions Act of 2008 Legislation  pdf format of Global Warming Solutions Act of 2008 Legislation

Massachusetts Clean Energy and Climate Plan for 2020  pdf format of Massachusetts Clean Energy and Climate Plan for 2020
file size 1MB

Global Warming Solutions Act 5-year Progress Report  pdf format of Global Warming Solutions Act 5-year Progress Report
file size 3MB

Department of Transportation:

Massachusetts Clean Energy Center:

Additional resources include local or municipal utility companies and the U.S. Environmental Protection Agency:

Emissions Factors

To calculate indirect emissions in compliance with the GHG Policy, use the CO2 emission factor determined by ISO New England.  As directed in the GHG Policy, the analysis should use the emission factor for annual average emissions based upon the most recent Electric Generator Air Emissions Report.  The most recent report was issued in December 2014. Check the ISO New England webpage (link below) prior to preparation of the analysis to confirm the correct emission factor is being used based upon the most recent report.  Recent emissions trends have fluctuated, downward and upward, from year to year, so care must be taken to check for new reporting documentation.

To determine the appropriate CO2 emission factor based on fuel type for direct emissions, refer to the Energy Information Administration Emissions Factor and Global Warming Potential Data:

Mobile emissions factors are based upon average emissions rates established as part of the U.S. EPA’s MOVES model. The MassDEP’s Air Quality Division is a good start for additional assistance on determining these mobile emissions factors as part of a project’s transportation and air quality analysis.

For more information on MassDEP’s Air Quality Division:

For a list of MassDEP Air Quality Division Contacts:

Massachusetts State Building Code

On July 1, 2014, the effective Building Energy Code for the State of Massachusetts changed to the 2012 International Energy Conservation Code (IECC) and the ASHRAE Standard 90.1-2010.  Although the standard “non-stretch” energy provisions of the code will be based on the IECC 2012 as of July 1, 2014, the Massachusetts Stretch Energy Code (Stretch Code) will continue to be based on amendments to the IECC 2009 (and ASHRAE 90.1-2007 for large commercial buildings) until such time as the Stretch Code is updated.

Projects that file ENFs after July 1, 2014 must use the updated State Building Code as the specified baseline for buildings.  Subsequent ENF Certificates will reference the version of the Building Code in effect at the time the ENF Certificate is issued.  Per the Policy, the Proponent may carry forward project modeling using that Building Code for the project baseline for the entire life of the project (even if the Building Code is updated during MEPA review), unless significant delays occur.  However, MEPA may recommend updating the baseline Building Code during the MEPA review process (e.g., between the ENF and the DEIR) to allow for a more realistic reflection of energy usage and mitigation measures based upon the Building Code that will be in effect at the time of construction commencement.

Until such time the updated Stretch Code is adopted, the Proponent may choose to either demonstrate compliance with the effective Stretch Code (outlined above), or in anticipation of a revised Stretch Code, select energy efficiency measures that achieve energy reductions between 12 and 15 percent beyond a project baseline modeled using the IECC 2012 or ASHRAE Standard 90.1-2010 requirements.  MEPA strongly recommends, for the purposes of MEPA review and demonstration that GHG emissions have been avoided, minimized and mitigated to the maximum extent practicable, that Proponents demonstrate consistency with the anticipated revised Stretch Code energy reductions.

For more information on the Massachusetts State Building Code:

For more information of the Stretch Energy Code:

Source Energy Path Calculations

Based on guidance previously provided by the DOER, MEPA has allowed the quantification of stationary source fuel consumption (e.g., on-site combined heat and power) using a source energy compliance path based on the results of site energy path modeling performed in compliance with the Mass Stretch Energy Code and converted using the site to source fuel conversion factors (SSFCF) in the table below. The source energy path will properly credit the efficiency of systems providing both electricity thermal energy as well as facilities purchasing district thermal energy provided by a CHP central plant which exports electrical generation to the power grid (e.g., the existing Dalkia (a.k.a. Kendall Station) district heating system in Cambridge). 

Site to Source Fuel Conversion Factors 1

Load Type


Electric power use at the utility meter 


Natural Gas


Fuel Oil




Purchased District Heating*

Hot Water





Purchased District Cooling


Fossil Fuels Not Listed


1 Conversion values in table are derived from the International Green Construction Code, ICC, 2012:


(*)DOER and MEPA have prepared a guidance document for those projects evaluating the potential benefits of connecting to the Dalkia district heating system in Cambridge that includes a site to source conversion factor for the facility and instruction on how to assess the potential CO2 benefits of connecting to this system in lieu of traditional energy sources.  This document is available upon request by contacting Holly Johnson at the MEPA office.

Selection of either the site or source pathway is at the project’s discretion.  The Proponent should contact MEPA or DOER staff prior to conducting an analysis using a source energy path to ensure that appropriate system details and assumptions are provided in the analysis to facilitate review.

Water and Wastewater Treatment Facility Energy Efficiency and GHG emissions

As outlined in the GHG Policy, projects that will consume greater than 300,000 gallons per day (gpd) of water or wastewater may be required, on a case-by-case basis, to model GHG emissions associated with energy usage for water or wastewater treatment.  Based upon data supplied by MassDEP, project proponents may use the following averages to estimate energy usage associated with water or wastewater treatment for the purposes of completing their GHG analysis. 

For projects located within Massachusetts Water Resources Authority (MWRA) communities:

  • Wastewater treatment average energy cost = 1.3 kWh/1,000 gallons treated
  • Water treatment average energy cost = 0.2 kWh/1,000 gallons treated

For projects located outside MWRA communities:

  • Wastewater treatment average energy cost = 1.7 kWh/1,000 gallons treated
  • Water treatment average energy cost = 1.1 kWh/1,000 gallons treated

Additionally, at the proponent’s discretion (and if applicable), the GHG analysis may use actual energy use data from community treatment plants in lieu of MassDEP’s average data, so long as supporting documentation is included in the MEPA filing.

MEPA is working with DOER to gather the most recent data on water and wastewater treatment energy costs based upon DOER data from a variety of facilities within the Commonwealth.  Once these data become available, they will be posted.

Energy Use Intensity (EUI)

EUI expresses a building’s energy use as a function of its size or other characteristics. A building’s EUI is generally expressed as energy per square foot per year.

The United States Energy Information Administration collects data nationwide as part of the Commercial Buildings Energy Consumption Survey (CBECS). These data can assist Proponents by informing the establishment of realistic building energy use baselines based upon proposed commercial building uses.

For more information:

While the most recently available data is from 2003, a new CBECS database (for year 2012) is anticipated to be available in mid to late 2015.  The MEPA Policy does not require calculation of an EUI for all projects subject to the GHG Policy. However, determining a building’s EUI is often required in conjunction with a number of energy reduction and management initiatives, ranging from calculating a project’s Energy Star score to complying with the Massachusetts Stretch Energy Code. 

If requested by DOER, MEPA generally requires that projects in communities that have adopted the Stretch Code calculated a Base Case and Preferred Case EUI. For projects in communities that have not adopted the Stretch Code, MEPA may recommend that a Base Case and Preferred Case EUI be calculated to assist in evaluation of energy efficiency and related GHG reductions. 

Tenant Manuals

Building-related energy efficiency measures can generally be attributable to core and shell improvements (e.g., energy-efficient boilers, efficient windows, etc.) or building operations.  GHG modeling is based on certain operational assumptions (e.g., hours of operation and related thermostat settings, plug loads for equipment, etc.). However, not all Proponents who prepare a GHG analysis will own and occupy the project. In many cases, a Proponent may design, construct, and own a building, but subsequently lease space to a third-party for fit-out and/or tenancy, or design and construct the core and shell of a building but then sell all or portions of the project to a third-party for interior fit-out and occupancy.

To promote consistency between modeled energy efficiency and GHG reductions and ensure that Damage to the Environment is being avoided, minimized and mitigated to the extent practicable by a Proponent, the MEPA office may request that a GHG analysis include preparation of a draft Tenant Manual to guide future fit-out and operations of a project consistent with the modeling assumptions or energy efficiency best management practices. 

Below are links to projects that included draft Tenant Manuals submitted in conjunction with a GHG analysis. The content of these draft Tenant Manuals is not intended to be comprehensive, but to give preparers an idea of the types of potential BMPs that a Proponent could consider for adoption.  Some measures may not be applicable, or feasible, for all projects.

EEA #14853 - Ink Block - BOSTON  pdf format of EEA #14853 - Ink Block - BOSTON
file size 1MB
EEA #14909 - New Brighton Landing - BOSTON  pdf format of EEA #14909 - New Brighton Landing - BOSTON
EEA #14944 - Athol Commons - ATHOL  pdf format of EEA #14944 - Athol Commons - ATHOL
file size 1MB
EEA #14945 - Millenium Tower - BOSTON  pdf format of EEA #14945 - Millenium Tower - BOSTON
file size 2MB
EEA #15052 -Boston Garden - BOSTON  pdf format of EEA #15052 -Boston Garden - BOSTON