NSTAR Electric Company d/b/a Eversource Energy: generator, battery backup & CPAP rules
Service area: Serves Boston, Cambridge and many other eastern Massachusetts communities, Cape Cod and Martha's Vineyard, the New Bedford area, and western Massachusetts around Springfield and Pittsfield.
Meter collar transfer switches
No published rule found
Massachusetts law (G.L. c. 164, sec. 151) says electric companies must authorize meter socket adapters that meet listed safety conditions, must decide on a model within 60 days of a request, and must post approved models on their websites. We found no Eversource list of approved meter socket adapters. In 2025 a state technical working group that includes Eversource, National Grid, Unitil and device makers was still developing the process for evaluating devices. Until Eversource publishes an approved list, ask Eversource before installing a Tesla Backup Switch, ConnectDER, GenerLink or Enphase IQ Meter Collar.
Generator and battery disconnect requirements
Eversource's eastern Massachusetts service manual says a standby generator must be wired so it cannot connect to Eversource's service at the same time, which requires a double-throw switch or an equivalent the company approves. You must notify Eversource and give details of how the generator is installed and isolated. Any generator or system that runs in parallel with the grid needs an interconnection application before it is installed, whatever its size. The manual says parallel generators are not allowed in the downtown network areas of Boston, Cambridge and New Bedford.
Gas meter upgrades for standby generators
Gas utility: Eversource Gas of Massachusetts or NSTAR Gas (Eversource) in many areas; other towns are served by National Grid, Unitil, Liberty, Berkshire Gas or a municipal utility.
We found no published Eversource fee or formal process for upgrading a gas meter for a standby generator. In Northampton and Easthampton, Eversource does not allow new gas service or added gas load because of pipeline limits, but it may allow emergency natural gas backup generators at its discretion for documented health reasons. For new meter sets, Eversource requires a pressure test by a licensed plumber, approved by the local inspector, before it installs the meter.
- Eversource: Northampton and Easthampton Gas Moratorium
- Eversource: Requirements for a Proper Meter Set Installation (eastern MA gas)
Estimate your gas load with our gas meter calculator and read how gas meter sizing works.
Medical program for CPAP, BiPAP and oxygen users
- Program
- Medical Certification of Illness (serious illness shutoff protection)
- What it provides
- Protects electric or gas service from shutoff when there is financial hardship in the home and a physician, Board of Health official, APRN or PA certifies a serious illness or serious chronic illness. It is not a discount, and you still owe the balance. The form asks whether the patient has life support equipment at home. Eversource says that if it is told life support equipment is operating at an address, it gives that address to municipal authorities for emergency response during outages.
- CPAP / BiPAP
- Not named. The form only asks whether the patient has life support equipment at home.
- Renewal
- Every 90 days for a serious illness; every 180 days for a serious chronic illness.
Backup battery or generator programs
- Program
- None found
- What it provides
- We found no Eversource backup battery or generator program or rebate for medical customers in Massachusetts.
Frequently asked questions
Does Eversource (MA) allow meter collar transfer switches like the Tesla Backup Switch?
No published rule found. Massachusetts law (G.L. c. 164, sec. 151) says electric companies must authorize meter socket adapters that meet listed safety conditions, must decide on a model within 60 days of a request, and must post approved models on their websites. We found no Eversource list of approved meter socket adapters. In 2025 a state technical working group that includes Eversource, National Grid, Unitil and device makers was still developing the process for evaluating devices. Until Eversource publishes an approved list, ask Eversource before installing a Tesla Backup Switch, ConnectDER, GenerLink or Enphase IQ Meter Collar.
Does Eversource (MA) have a program for customers who use a CPAP or other medical equipment?
Medical Certification of Illness (serious illness shutoff protection): Protects electric or gas service from shutoff when there is financial hardship in the home and a physician, Board of Health official, APRN or PA certifies a serious illness or serious chronic illness. It is not a discount, and you still owe the balance. The form asks whether the patient has life support equipment at home. Eversource says that if it is told life support equipment is operating at an address, it gives that address to municipal authorities for emergency response during outages. Not named. The form only asks whether the patient has life support equipment at home.
Does Eversource (MA) offer backup batteries or generator rebates for medical customers?
We did not find a current backup battery or generator program for medical customers at Eversource (MA). We found no Eversource backup battery or generator program or rebate for medical customers in Massachusetts.
How do I get a bigger gas meter for a standby generator in the Eversource (MA) area?
Eversource Gas of Massachusetts or NSTAR Gas (Eversource) in many areas; other towns are served by National Grid, Unitil, Liberty, Berkshire Gas or a municipal utility.: We found no published Eversource fee or formal process for upgrading a gas meter for a standby generator. In Northampton and Easthampton, Eversource does not allow new gas service or added gas load because of pipeline limits, but it may allow emergency natural gas backup generators at its discretion for documented health reasons. For new meter sets, Eversource requires a pressure test by a licensed plumber, approved by the local inspector, before it installs the meter.