Solar Panel Angle Guide
Solar Panel Angle in Washington
Washington, United States is at latitude 38.91°N. Here's the optimal solar panel tilt and orientation for maximum energy production.
Year-Round Tilt
36.9°
Summer Tilt
23.9°
Winter Tilt
53.9°
Face
South
180° azimuth
Monthly Optimal Tilts for Washington
Jan
59.2°
Feb
50.6°
Mar
38.9°
Apr
27.2°
May
18.6°
Jun
15.5°
Jul
18.6°
Aug
27.2°
Sep
38.9°
Oct
50.6°
Nov
59.2°
Dec
60.0°
Ideal: 62.4°
Peak Sun Hours
4.5 hrs/day
Average daily solar insolation
Annual Production (400W panel)
~657 kWh
At 36.9° tilt, facing South
Solar Panel Recommendations for Washington
- Fixed mount: Set your panels at 36.9° tilt, facing South (180° azimuth).
- Seasonal adjustment: Tilt to 23.9° in summer and 53.9° in winter for up to 15% more annual energy.
- Monthly adjustment: Adjust tilt each month using the table above for maximum year-round production.
Solar in the Nation's Capital
Washington DC receives approximately 4.5 peak sun hours daily, providing solid solar potential for the mid-Atlantic region. The climate features hot, humid summers and mild winters, with moderate cloud cover throughout the year. DC's latitude of 38.9°N produces meaningful seasonal variation in solar production, with summer substantially outperforming winter.
The District of Columbia has one of the strongest SREC (Solar Renewable Energy Certificate) markets in the country, driven by the city's aggressive renewable portfolio standard. PEPCO offers net metering, and the SREC income adds a significant revenue stream beyond electric bill savings. These policies have made Washington DC one of the top solar markets in the mid-Atlantic.
DC's urban environment includes a mix of historic row houses and modern single-family homes. Historic preservation restrictions can affect solar installations in some neighborhoods. The region's tree canopy — particularly in established neighborhoods like Capitol Hill and Chevy Chase — requires careful shading analysis. Flat roofs are common in DC row houses and accommodate solar well using ballasted mounting systems.
Orientation Performance
Panel orientation significantly affects energy production. The table below shows relative output compared to true south-facing panels:
| Orientation | Relative Output |
|---|---|
| South | 100% |
| South-East | 96% |
| South-West | 96% |
| East | 85-90% |
| West | 85-90% |
| North | 60-75% |
Frequently Asked Questions
Is DC good for solar?
DC averages 4.5 peak sun hours with strong SREC market and net metering through PEPCO. The District also has a renewable portfolio standard that drives solar adoption.
How much energy can a 400W panel generate here?
With 4.5 peak sun hours per day, a properly aligned 400W panel could generate approximately 657 kWh per year.
Related Calculators
Solar Panel Tilt Calculator
Calculate optimal tilt for any latitude and month
Solar Panel Azimuth Calculator
Find the exact compass heading for your panels
Get exact numbers with the SolarAlign app
Use your phone to align panels in real-time with live sensor feedback.Learn more →