The Massachusetts Department of Energy Resources (DOER) is continuing the regulatory process in revising the APS (225 CMR 16.00) to incorporate the eligibility of renewable thermal technologies. The most recent draft regulations were filed on June 2, 2017. The revisions have not yet been finalized as DOER is reviewing comments received from the public hearings and comment period, which concluded on August 7, 2017.

Eligible Technologies

Under the latest draft, technologies that are included to receive credits for thermal generation include:

  • Air-Source Heat Pump
  • Ground Source Heat Pump
  • Deep Geothermal Heat Exchange
  • Solar Thermal
  • Woody Biomass
  • Biogas
  • Liquid Biofuels

Technologies can earn APS credits for each net MWh of new useful thermal energy generated on a quarterly basis. The calculations for APS credits vary by technology and size.

The revisions also establish provisions for alternative energy credit (AEC) “multipliers”, where one unit of energy production earns two or more credits. Renewable thermal generation units that do not emit criteria air pollutants are eligible for these extra AECs per unit of thermal production. Multipliers are also based on system size.  A summary of the AEC multipliers is provided in Table 1.

AEC Multiplier for Non-Emitting Technologies

Non-Emitting Technology AEC Multiplier
System size Small Intermediate Large
Active solar hot water systems used for domestic hot water 3 3 3
Active solar hot water systems used for domestic hot water and/or space heating 1 1 1
Active solar hot air systems 5 5
Solar sludge dryer 1
Ground source heat pumps 5 5 5
Deep geothermal 1
Air source heat pumps (electric or engine driven) – partial system 2 1 1
Air source heat pump (electric or engine driven) – all other 3 3 3
Biomass, biofuels, biogas N/A N/A N/A

A renewable thermal generation unit will retain the multiplier provided at the outset for its lifetime. DOER may re-evaluate the multipliers periodically considering several factors including observed market uptake of the different technologies, rebates, and grants available from federal or state agencies.

In addition, any small ground source heat pump or air source heat pump installed in a building will be given an additional multiplier of 2 (added to the base multiplier) if:

  • The residential building achieves a Home Energy Rating System (HERS) Index rating of 50 or less, or
  • The non-residential building meets the definition of “Zero Energy” as defined by the U.S. Department of Energy.

It is expected that the regulations will be finalized at some point in Q4 2017. Once the qualification and metering requirements are finalized, Next Grid can work with you to enroll in the program.

For more information on the regulations, please refer to this link: