Calculator › Boston, Massachusetts
Solar panels in Boston, Massachusetts
Boston receives 3.87 peak sun hours a day and 1,412 kWh/m² of solar energy a year. That is measured satellite data for Boston's coordinates, not a national average — and it changes the panel count.
Boston solar data
3.87peak sun hours/day
1,412annual irradiance (kWh/m²)
1.28kWh/day from one 400 W panel
466kWh/year from one 400 W panel
Monthly solar irradiance in Boston
| Month | Peak sun hours/day | Share of year |
|---|---|---|
| January | 1.61 | 0.1 |
| February | 3.04 | 0.3 |
| March | 3.67 | 0.3 |
| April | 4.47 | 0.4 |
| May | 5.23 | 0.4 |
| June | 6.16 | 0.5 |
| July | 5.83 | 0.5 |
| August | 4.79 | 0.4 |
| September | 4.25 | 0.4 |
| October | 3.26 | 0.3 |
| November | 2.30 | 0.2 |
| December | 1.68 | 0.1 |
Source: NASA POWER daily point API, parameter ALLSKY_SFC_SW_DWN (global horizontal irradiance), year 2024. Coordinates 42.3601, -71.0589.
How many solar panels does Boston need?
For a typical US household using 900 kWh a month, Boston needs about 24 panels of 400 W (9.39 kWp), with a south-facing roof. That is more panels than the same household would need in a city with 4.5 peak sun hours.