Solar in Massachusetts: payback, sun by city and utility-scale capacity
Massachusetts pays back in 7.7 years at $3.00 a watt (rank 3 of 51), 5.8 years shorter than the middle state. 1,277 kWh per kW (rank 41) at 30.48 ¢ (rank 3 from the top): price of power drives it. Across 5 Massachusetts cities, yearly output runs from 1,211 kWh per kW in Pittsfield to 1,330 in New Bedford. Jul is the best month at 141 kWh per kW and Dec the worst at 64. Utility-scale solar in Massachusetts: 1,503 MW in 557 plants, 9.2% of 2025 generation; 59 MW more under construction or planned.
Massachusetts: payback 7.7 years, rank 3 of 51
| Measure | Value | Rank of 51 | Median state |
|---|---|---|---|
| Output of 1 kW a year, kWh | 1,277 | 41 | 1,372 |
| Home price, ¢ per kWh | 30.48 | 3 | 15.37 |
| Value of 1 kW a year | $389 | 3 | $222 |
| Payback at $3.00 a watt | 7.7 years | 3 | 13.5 years |
EIA-861 (2024): 189,826 home net-metered systems in Massachusetts, 64.9 per 1,000 accounts (rank 7), average 6.9 kW.
Sizes and prices per watt in Massachusetts
| Massachusetts kW | kWh a year | Value a year | Cost at $2.50 | At $3.00 | At $3.50 | t CO2 |
|---|---|---|---|---|---|---|
| 4 | 5,108 | $1,557 | $10,000 | $12,000 | $14,000 | 1.9 |
| 6 | 7,663 | $2,336 | $15,000 | $18,000 | $21,000 | 2.9 |
| 8 | 10,217 | $3,114 | $20,000 | $24,000 | $28,000 | 3.8 |
| 10 | 12,771 | $3,893 | $25,000 | $30,000 | $35,000 | 4.8 |
| 12 | 15,325 | $4,671 | $30,000 | $36,000 | $42,000 | 5.7 |
| Massachusetts $ per watt | 100% retail | 75% | 50% | 25% |
|---|---|---|---|---|
| $2.00 | 5.1 | 6.9 | 10.3 | 20.6 |
| $2.50 | 6.4 | 8.6 | 12.8 | 25.7 |
| $3.00 | 7.7 | 10.3 | 15.4 | 30.8 |
| $3.50 | 9.0 | 12.0 | 18.0 | 36.0 |
| $4.00 | 10.3 | 13.7 | 20.6 | 41.1 |
Massachusetts: 1,277 kWh/kW × 30.48 ¢ = 389 a year per kW; the 30% column (5.4 years at $3.00) is arithmetic only.
CSVSun inside Massachusetts: 5 cities, 9% apart
| Massachusetts city | kWh per kW a year | Against state point | Sun, kWh/m2 a day | Payback at $3.00 | Residents |
|---|---|---|---|---|---|
| Boston | 1,275 | -0.2% | 4.59 | 7.7 | 663,972 |
| Worcester | 1,280 | +0.3% | 4.69 | 7.7 | 205,501 |
| Springfield | 1,260 | -1.4% | 4.64 | 7.8 | 154,751 |
| New Bedford | 1,330 | +4.2% | 4.69 | 7.4 | 100,731 |
| Pittsfield | 1,211 | -5.2% | 4.43 | 8.1 | 43,559 |
Massachusetts state point 42.29, -71.31; city points Boston 42.34, -71.02; Worcester 42.27, -71.81; Springfield 42.12, -72.54; New Bedford 41.66, -70.94; Pittsfield 42.45, -73.26. Panel and method: solar method.
Output by month in Massachusetts cities: 12 rows
| Massachusetts month | Boston | Worcester | Springfield | New Bedford | Pittsfield |
|---|---|---|---|---|---|
| Jan | 73.0 | 77.6 | 73.8 | 75.8 | 73.2 |
| Feb | 89.1 | 94.8 | 88.0 | 90.1 | 83.9 |
| Mar | 123.2 | 124.0 | 121.7 | 119.2 | 117.5 |
| Apr | 122.7 | 125.1 | 114.0 | 123.0 | 111.1 |
| May | 139.0 | 130.2 | 132.9 | 140.6 | 126.0 |
| Jun | 126.3 | 128.7 | 126.3 | 134.1 | 119.1 |
| Jul | 135.3 | 136.3 | 135.3 | 144.4 | 135.0 |
| Aug | 128.0 | 125.7 | 129.3 | 136.7 | 125.0 |
| Sep | 114.1 | 110.1 | 113.3 | 119.3 | 113.9 |
| Oct | 90.3 | 87.3 | 91.4 | 100.5 | 83.8 |
| Nov | 69.1 | 75.3 | 71.8 | 78.7 | 66.7 |
| Dec | 64.6 | 65.1 | 61.8 | 67.6 | 56.2 |
Massachusetts: 5 cities, best month 144 and worst 56 kWh per kW across them.
CSVBest and worst month in Massachusetts: Jul 141, Dec 64 kWh per kW
| Massachusetts month | kWh per kW | Price ¢ | Value per kW | kWh per kW per sun unit |
|---|---|---|---|---|
| Jan | 80.9 | 30.07 | $24.33 | 0.83 |
| Feb | 88.6 | 30.42 | $26.95 | 0.82 |
| Mar | 113.5 | 30.18 | $34.25 | 0.80 |
| Apr | 125.7 | 30.63 | $38.50 | 0.75 |
| May | 124.6 | 29.90 | $37.26 | 0.74 |
| Jun | 128.5 | 30.33 | $38.97 | 0.72 |
| Jul | 141.4 | 30.07 | $42.52 | 0.71 |
| Aug | 129.1 | 30.61 | $39.52 | 0.71 |
| Sep | 113.8 | 30.41 | $34.61 | 0.73 |
| Oct | 89.8 | 31.37 | $28.17 | 0.76 |
| Nov | 76.8 | 31.22 | $23.98 | 0.81 |
| Dec | 64.2 | 30.88 | $19.82 | 0.82 |
Massachusetts: December to February give 18% of a year (rank 27 of 51, 1 = most winter); the best month is 2.2 times the worst. Output per unit of sun is highest in Jan (0.83) and lowest in Jul (0.71); PVWatts lowers cell output when the panel is hot, and the sun angle changes with the season. Our runs use one fixed 14% loss figure for every place, so snow or soiling in Massachusetts is not modelled separately.
Utility-scale solar in Massachusetts: 1,503 MW
Massachusetts: 1,503 MW of operable utility-scale solar in 557 plants across 13 counties (EIA-860, 2025), rank 22 of 51; 215 W per resident, rank 32. Solar made 9.2% of Massachusetts's net generation in 2025 (EIA-923), rank 13, +2.5 points against the national share. Biggest plants: SJA Solar LLC-Solterra Monastery CSG in Worcester County, 15 MW (2016); Barrett PV in Worcester County, 12 MW (2016); NL MA - Copicut in Bristol County, 8 MW (2025). By county: Worcester 463 MW, Hampden 185 MW, Plymouth 176 MW, Bristol 148 MW. Proposed: 22 MW under construction (6 plants) and 37 MW planned (9 plants); batteries 492 MW running and 924 MW proposed.
| Massachusetts year | MW added | Cumulative share of today's MW |
|---|---|---|
| 2019 | 110 | 7% |
| 2020 | 139 | 17% |
| 2021 | 204 | 30% |
| 2022 | 97 | 37% |
| 2023 | 44 | 39% |
| 2024 | 22 | 41% |
| 2025 | 44 | 44% |
Net metering and CO2 in Massachusetts
EIA-861 (2024): 189,826 home net-metered systems in Massachusetts, 64.9 per 1,000 accounts (rank 7), average 6.9 kW.
6 kW in Massachusetts: 7,663 kWh a year displaces 2.9 t CO2 at 0.373 kg per kWh, -0.2 t against the average state.
Massachusetts utilities and solar payback
| Massachusetts utility | Homes | Price ¢ | Value of 1 kW | Payback at $3.00 |
|---|---|---|---|---|
| NSTAR Electric Company | 1,303,076 | 19.92 | $254 | 11.8 yr |
| Massachusetts Electric Co | 1,210,113 | 23.07 | $295 | 10.2 yr |
| City of Taunton | 35,684 | 21.46 | $274 | 10.9 yr |
| Town of Reading | 27,405 | 15.86 | $203 | 14.8 yr |
| Fitchburg Gas & Elec Light Co | 26,290 | 23.97 | $306 | 9.8 yr |
| City of Chicopee | 23,218 | 16.16 | $206 | 14.5 yr |
| City of Peabody | 22,546 | 15.71 | $201 | 15.0 yr |
| City of Westfield | 16,200 | 17.59 | $225 | 13.4 yr |
| Town of Shrewsbury | 15,713 | 14.27 | $182 | 16.5 yr |
| City of Holyoke | 15,040 | 16.58 | $212 | 14.2 yr |
| Town of Middleborough | 14,884 | 15.84 | $202 | 14.8 yr |
| Town of Braintree | 14,039 | 15.79 | $202 | 14.9 yr |
Massachusetts among its neighbours
| Closest to Massachusetts | Payback, years | kWh per kW | Price, ¢ | Utility-scale solar, points of generation | Miles away |
|---|---|---|---|---|---|
| Massachusetts (this page) | 7.7 | 1,277 | 30.48 | 9.2 | - |
| Rhode Island | +0.2 | +18 | -1.02 | -2.2 | 36 |
| New Hampshire | +2.0 | -19 | -5.92 | -9.2 | 60 |
| Connecticut | +0.3 | +5 | -1.10 | -7.7 | 102 |
| Vermont | +3.0 | -52 | -7.56 | +1.1 | 148 |
Massachusetts against its neighbours in the payback ranking
- -1 places, Hawaii -3.4 years against Massachusetts
- +0 places, California -2.2 years against Massachusetts
- Massachusetts, rank 3: 7.7 years
- +2 places, Rhode Island +0.2 years against Massachusetts
- +3 places, Connecticut +0.3 years against Massachusetts
Your numbers for Massachusetts
Limits in Massachusetts
Massachusetts: with the old 30% credit (IRS, ended 2025) payback would be 5.4 years instead of 7.7, so the calculator starts at 0%. No Massachusetts export rates in our data: output counts at 30.48 ¢. All limits.
Sources for Massachusetts
- PVWatts v8 (NLR), 5 Massachusetts cities and one state point: 1,277 kWh per kW
- EIA-860 2025 and EIA-923 2025: 1,503 MW of solar in Massachusetts
- EIA-861 2024: 189,826 net-metered systems in Massachusetts
- EIA retail sales 2025: 30.48 ¢ per kWh in Massachusetts
- IRS 25D (ended 2025): 5.4 years in Massachusetts with it; licences and periods for Massachusetts
More about Massachusetts
Massachusetts electricity hub, Massachusetts EV charging: 4,568 stations, where Massachusetts ranks for rooftop solar, 7.7 years against 51 states, Massachusetts calculators.
Questions
Solar payback in Massachusetts?
7.7 years at $3.00 a watt; 6.4 at $2.50; 9.0 at $3.50; 1,277 kWh per kW at 30.48 ¢.
Net metering in Massachusetts?
189,826 systems, 64.9 per 1,000 accounts, rank 7.
Massachusetts sunshine for solar panels?
1,277 kWh per kW a year at the state point, rank 41 of 51; from 1,211 in Pittsfield to 1,330 in New Bedford.
Massachusetts electricity from solar, what share?
9.2% of 2025 net generation, rank 13 of 51, +2.5 points against the nation.
Where in Massachusetts is solar best?
Yes: 9% between Pittsfield and New Bedford in yearly output.
Massachusetts utility-scale solar capacity?
1,503 MW in 557 plants (EIA-860), 215 W per resident, rank 32; 59 MW proposed.
Winter cut in Massachusetts solar output?
December to February give 18% of the year; Jul makes 141 kWh per kW and Dec 64.
Massachusetts pays half price for exports?
Payback 15.4 years at a 50% retail share.
CO2 displaced in Massachusetts?
2.9 t a year on 6 kW at 0.373 kg per kWh.
Federal solar credit in Massachusetts: still available?
Ended 2025 (IRS 25D); with it Massachusetts payback would be 5.4 years, not 7.7.