Solar Atlas · Massachusetts
Is solar worth it in Boston, MA?
A 7 kWdc rooftop array in Boston makes about 9,114 kWh a year (NLR PVWatts, modeled) and pays back in 8.1 years at NSTAR Electric Company’s 31.1¢/kWh residential rate (2026 est.), with no federal credit. Exports follow Massachusetts net metering (Class I, cap-exempt).
42.36°N · 8.9–15.1 h daylight · site signature
- Production
- 1,302 kWh per kWdc per year · capacity factor 14.9% AC
- Residential rate
- 31.1¢/kWh · NSTAR Electric Company
- Exported solar
- Massachusetts net metering (Class I, cap-exempt) · credited at retail
- Climate
- hot-summer humid continental (Köppen Dfa) · 11.0 °C mean, 1,107 mm/yr
Source: NLR PVWatts v8.5.0 (NSRDB PSM V3 GOES tmy-2020 3.2.0) — 1 kW, tilt 20°, azimuth 180°, roof mount, 14% losses · fetched 2026-09-24 · modeled, not metered
Source: EIA-861 2024 utility average × EIA state trend · 2026 est. · EIA Massachusetts average Jan–Jul 2026 30.1¢ · utility’s EIA-861 2024 average 29.9¢
NSTAR Electric Company customers who buy supply from a competitive supplier or community choice aggregator pay delivery plus their supplier’s price; the average shown is the utility’s default (bundled) service.
Source: Customers of Massachusetts distribution companies (Eversource, National Grid, Unitil) with solar ≤ 25 kW, which is exempt from the net metering caps · checked 2026-09-25
Source: NOAA NCEI Climate Normals 1991–2020, BOSTON LOGAN INTL AP, MA US (4.1 km away) · fetched 2026-09-24
No federal credit: the homeowner credit (§25D) ended for systems installed after 2025-12-31. A lease or PPA price may reflect the lessor’s §48E credit. 26 U.S.C. §25D(h) and (e)(8)(A) · policy as of 2026-09-24
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Start from your bill. Everything else is prefilled from this page and can be changed.
Your exact roof, or a business
The payback calculator runs hourly PVWatts at your address. The Modeler opens a grid-tied home at Boston. A business goes to the Quote Studio with the 32.1¢/kWh commercial rate.