Massachusetts Home Battery Payback Calculator (2026)
Priced on Eversource / National Grid Standard (flat) rates and full-retail export rules. No federal tax credit is assumed — Section 25D ended 2025-12-31.
Why Massachusetts is different
Massachusetts is the honest negative case. The state's net-metering rules credit solar exports at full retail on a flat rate — the grid already acts as a free battery for your solar, so storing energy instead of exporting it reduces your bill by exactly zero. At 30.5-cent average retail rates that is not a rounding error; it is the whole calculation. The battery case here rests on two things the calculator keeps separate from bill savings: ConnectedSolutions, the Eversource / National Grid demand-response program (roughly $275 per kW-year reported, paid for dispatch readiness), and outage backup in a state where Nor'easters routinely cut power for days. If a Massachusetts quote is justified on bill savings alone, it is not justified.
Rate structure
| Rate | Value | Notes |
|---|---|---|
| Peak rate (discharge window) | $0.30/kWh · flat rate — same price every hour | |
| Off-peak rate (charging) | $0.30/kWh | |
| Export credit | $0.30/kWh · Full-retail net metering (≤10 kW) | |
| Average residential retail | $0.305/kWh · EIA statewide residential average 30.49¢ (2026-07); Eversource basic service of 17.3¢ is supply-only, while the full bill runs about 29-30¢ |
Verification status: Sourced. Flat rates (the EIA statewide average stands in for the all-in retail rate)
Export mechanism: full-retail export
In Massachusetts, Full-retail net metering (≤10 kW) — storing solar instead of exporting it does not reduce your bill. Custom rates that credit exports below retail flip this mechanism; turn on 'use my own electricity prices' in the calculator to model that plan.
Incentives and VPP
| Program | Status | What it means for a battery |
|---|---|---|
| ConnectedSolutions (VPP) / 15% solar credit | Active | ConnectedSolutions pays ~$275/kW-yr (demand response, not an upfront rebate); the 15% state credit ($1,000 cap) applies to solar, not batteries |
| Virtual power plant (VPP) | verify | typically ~$275/kW-yr (≈$1,100-1,400/summer) — verify current program year |
Outage context
Winter storms and nor'easters make backup valuable
Typical payback in Massachusetts
Precomputed with the same model as the calculator, at the Massachusetts rates above and the reference installed cost of $16,000 (13.5 kWh usable, pre-incentive). Your numbers move with your bill, your quote and your rate plan.
| Scenario | Year-1 savings | Simple payback | 10-year net |
|---|---|---|---|
| Have solar · $200/mo bill · 13.5 kWh · $16,000 installed | $0 | — | −$16,000 |
| Have solar · larger bill · $600/mo bill · 13.5 kWh · $16,000 installed | $0 | — | −$16,000 |
| Battery only · $200/mo bill · 13.5 kWh · $16,000 installed | $0 | — | −$16,000 |
Estimates only — not financial, tax, or installation advice. Backup value and program payments are shown separately and never folded into the payback ratio.
State data pack
| Field | Value |
|---|---|
| Default utility | Eversource / National Grid |
| Rate plan modelled | Standard (flat) |
| Average residential retail | $0.305/kWh |
| Verification status | Sourced |
| Data as of | 2026-10-18 |
| Official sources | EIA Electric Power Monthly Table 5.6.A (MA residential average) (2026-10-18) · Massachusetts rates & ConnectedSolutions overview (2026-10-18) · Massachusetts all-in rate & net metering (EIA-cited) (2026-10-18) |
Frequently asked questions
How much can a battery actually save on my Massachusetts bill?
On bill savings alone, the model's honest answer for a default Massachusetts flat-rate plan is about $0: exports are credited at or near retail, so storing solar does not reduce your bill. The value case rests on backup power and VPP payments, which the results screen shows separately and never folds into the payback ratio.
Does Massachusetts pay for home batteries?
ConnectedSolutions pays ~$275/kW-yr (demand response, not an upfront rebate); the 15% state credit ($1,000 cap) applies to solar, not batteries Program terms change mid-cycle — verify on the program's own page before counting on any rebate.
Is a battery worth it in Massachusetts without the federal tax credit?
Section 25D ended 2025-12-31, so every result on this site assumes no federal credit. That makes the break-even installed price the most useful number on the results screen: it is the price at which the ten-year arithmetic stops working at your assumptions. Compare every quote against it, and read the outage context above — backup is real value, just not a cash flow.
Calculate with Massachusetts data →
Keep reading
| All state guides — ten states, ten different answers | Directory |
| Data & method — every constant with its source and verification date | Data |
| Full guide — how to read a payback number and the mistakes that inflate it | Article |
| How the model works — included, excluded, and a worked example | Method |
This page is educational. It is not financial, tax, or installation advice. Data as of 2026-10-18.