Balcony solar in Columbia
800 W of panels on a south-facing balcony railing in Columbia produce about 730 kWh a year and save about $84.
Output by orientation and mounting
Yearly output with 800 W of panels and the inverter limited to 800 W.
| Panels face | On the railing (vertical) | Tilted at 30° |
|---|---|---|
| East | 530 kWh | 890 kWh |
| South-east | 690 kWh | 1,030 kWh |
| South | 730 kWh | 1,090 kWh |
| South-west | 680 kWh | 1,030 kWh |
| West | 520 kWh | 880 kWh |
Output by month
Show as a table
| Month | Railing (vertical) | Tilted at 30° |
|---|---|---|
| Jan | 78 kWh | 74 kWh |
| Feb | 73 kWh | 80 kWh |
| Mar | 71 kWh | 97 kWh |
| Apr | 59 kWh | 110 kWh |
| May | 48 kWh | 110 kWh |
| Jun | 40 kWh | 110 kWh |
| Jul | 44 kWh | 110 kWh |
| Aug | 53 kWh | 110 kWh |
| Sep | 55 kWh | 85 kWh |
| Oct | 68 kWh | 81 kWh |
| Nov | 76 kWh | 75 kWh |
| Dec | 64 kWh | 59 kWh |
Savings and payback
At $0.2132 per kWh you save about $84 in the first year. A kit costing $1,300 pays back in about 15.4 years.
- Electricity price: $0.2132 per kWh (U.S. Energy Information Administration, 2025-09..2026-08). Source
- Assumes a constant base load of 150 W, so 54% of the output is used at home.
- Power sent to the grid is not paid for.
Rules
Maryland
In effect since July 1, 2026
Up to 1,200 W of inverter output per meter.
- Certified by UL or an equivalent nationally recognized testing laboratory. Kits of 391 W or less are exempt from listing provisions that would require rewiring.
- You must notify the utility before connecting.
Last verified: October 31, 2026
Nearby cities
- Baltimore 720 kWh a year · 13 mi
- Germantown 730 kWh a year · 24 mi
Data sources
- Solar data: PVGIS-NSRDB, PVGIS 5.2, 2011–2015.
- Electricity price: U.S. Energy Information Administration, 2025-09..2026-08.
- Last verified: October 31, 2026
- How we calculate