Waltham, Massachusetts
Home Battery Backup in Waltham
Waltham Community Electricity locked supply prices from December 2025 to December 2029, below Eversource Basic Service. A battery doesn't change that price. It earns ConnectedSolutions payments in summer and keeps the house running when Eversource's lines are down.
WCE 13.599¢ default, fixed to Dec 2029 · Eversource Basic 17.323¢ · ConnectedSolutions $275/kW.
The short answer
Waltham is Eversource territory, and most homes buy supply through Waltham Community Electricity, fixed at 13.200–14.080¢ per kWh until December 2029. Eversource Basic Service is 17.323¢ through January 2027.
A battery doesn't touch the supply price. It earns Mass Save's ConnectedSolutions, $275 per kW of average summer-event contribution, and covers outages. If you heat with a heat pump, size for winter too.
Get a Free Estimate
Tell us your Waltham address, how the house is heated and what must stay on in an outage. We confirm Eversource delivery, check where a battery can legally go on your lot and walk through ConnectedSolutions before anyone sizes a system.
What's different about Waltham
Same Eversource wires as its neighbors, but a longer fixed supply term than Framingham, Somerville or Newton.
Supply locked to December 2029
Waltham Community Electricity's current prices run 48 months, from December 2025 to December 2029 meter reads: Waltham Basic 13.200¢, Waltham Standard (the default) 13.599¢ and Waltham Plus 14.080¢ per kWh.
Eversource still delivers
The program only changes who supplies your electricity. Eversource handles delivery, billing and outages. Eversource's own residential Basic Service supply is 17.323¢ from August 2026 to January 2027.
Solar credits carry over
The City's program site says solar customers keep their net metering credits while in Waltham Community Electricity, and you can leave the program at any time without a penalty.
What a Waltham battery actually has to do
Summer pays; winter is where a heat-pump house needs the backup.
ConnectedSolutions pays $275 per kW
Mass Save's ConnectedSolutions pays $275 per kW of a battery's average contribution during summer events, held on non-holidays from June 1 to September 30 between 3 and 8 p.m., for up to three hours. Its example: a 5 kW battery could earn up to $1,375 a year.
Heat pumps change the winter load
Since November 1, 2025, Eversource has offered a reduced delivery rate from November through April for most homes with heat pumps. The program site cites a Mass. DPU estimate of about $540 a winter. That makes winter the season a heat-pump house leans hardest on the grid.
Size backup for a winter outage
If the heat pump is on the critical-load list, the battery has to cover it during the season ConnectedSolutions doesn't pay for. That's a sizing decision, not a rate one.
Backup is the part that's certain
A supply price doesn't keep the lights on when a line drops. Grid-tied solar shuts off in an outage unless it's paired with storage and a transfer switch.
Waltham next to Newton and Framingham
Next door, Newton has its own aggregation program on the same Eversource wires. Farther west, Framingham's fixed prices end in March 2027 with the next price unannounced. Waltham's run to December 2029. For the water side of this city, see Waltham water quality.
Where these figures come from
Everything on this page traces to the City of Waltham's program and Mass Save.
- Waltham Community Electricity (City of Waltham program) — current prices and term, Eversource Basic Service, net metering, low-income and heat pump rates.
- Mass Save — Batteries and ConnectedSolutions — the $275/kW payment, event window and the 5 kW example.
What a home battery job with us covers
Installation of storage and the backup circuits behind it, with the siting and utility paperwork handled.
Battery installation
Wall or floor-mounted storage installed to the listing and to the residential code sections that govern where it may go.
Backup and critical load panel
Deciding and wiring which circuits stay live, and which must never be on backup — the choice that defines what an outage feels like.
Integration with existing PV solar
Connecting storage to an array that is already on the roof, including whether the existing inverter supports it.
Transfer switch and disconnection
The equipment that separates the house from the grid during an outage, which is what makes backup legal as well as possible.
Siting to code
Location, clearances, separation and impact protection assessed against the adopted code before anything is mounted.
Permit, inspection and utility approval
The electrical permit, the inspection, and the utility's own approval step where storage touches the service.
This is installation work. No runtime, capacity or incentive figure is quoted before your loads and your utility are confirmed. Coverage is confirmed per service area rather than promised as blanket availability.
What the work actually looks like
A battery job is an electrical job. The panel, the circuits and the disconnection are most of it.
Waltham battery backup, answered plainly
Who delivers electricity in Waltham?+
Eversource. Waltham Community Electricity changes the supplier and supply price for participants, but Eversource still handles delivery, billing and outages.
What does Waltham Community Electricity cost?+
From December 2025 to December 2029 meter reads: Waltham Basic 13.200¢, Waltham Standard 13.599¢ (the default) and Waltham Plus 14.080¢ per kWh. Eversource residential Basic Service is 17.323¢ from August 1, 2026 to January 31, 2027. The City notes savings can't be guaranteed.
Does a battery lower my Waltham supply price?+
No. Your supply price comes from the City program or Eversource Basic Service. A battery adds ConnectedSolutions payments for summer peak events and backup power when Eversource's lines are down.
What does ConnectedSolutions pay in Waltham?+
Mass Save pays $275 per kW of your battery's average contribution during summer events, June 1 to September 30, 3 to 8 p.m., up to three hours each. A battery holding 5 kW through events could earn up to $1,375 a year.
I have a heat pump. Does that change the battery?+
It can. Eversource's heat pump delivery rate lowers winter delivery charges, which makes the heat pump the biggest winter load in the house. If it needs to run in an outage, it goes on the critical-load panel and drives battery size.
Who installs it, and who is responsible afterwards?+
Seamless Home is the licensed contractor of record on the work it runs. Installation is performed by vetted installing partners engaged as our subcontractors. Coverage is confirmed per service area rather than promised as blanket availability.
Related resources
Home battery backup
The national service page behind this one.
Learn more →Newton battery backup
Eversource wires with Newton's own aggregation price.
Learn more →Framingham battery backup
Aggregation prices that end in March 2027.
Learn more →Waltham water quality
MWRA water and Waltham's own local results.
Learn more →All home services
Water, battery, HVAC and solar under one licensed contractor of record.
Learn more →Get a free battery estimate
Tell us your Waltham address and what must stay on in an outage. We confirm Eversource delivery, check siting on your lot and size to a critical load panel — no obligation.
Get a Free Estimate