Balcony solar in Roanoke
800 W of panels on a south-facing balcony railing in Roanoke produce about 740 kWh a year and save about $67.
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 | 550 kWh | 920 kWh |
| South-east | 700 kWh | 1,070 kWh |
| South | 740 kWh | 1,120 kWh |
| South-west | 690 kWh | 1,060 kWh |
| West | 530 kWh | 910 kWh |
Output by month
Show as a table
| Month | Railing (vertical) | Tilted at 30° |
|---|---|---|
| Jan | 83 kWh | 79 kWh |
| Feb | 72 kWh | 81 kWh |
| Mar | 69 kWh | 98 kWh |
| Apr | 57 kWh | 110 kWh |
| May | 46 kWh | 120 kWh |
| Jun | 39 kWh | 110 kWh |
| Jul | 41 kWh | 110 kWh |
| Aug | 50 kWh | 100 kWh |
| Sep | 50 kWh | 81 kWh |
| Oct | 75 kWh | 91 kWh |
| Nov | 83 kWh | 84 kWh |
| Dec | 73 kWh | 68 kWh |
Savings and payback
At $0.167 per kWh you save about $67 in the first year. A kit costing $1,300 pays back in about 19.4 years.
- Electricity price: $0.167 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
Virginia
Takes effect on January 1, 2027
Up to 1,200 W of inverter output per home.
- Certified by a nationally recognized testing laboratory and meets the current National Electrical Code; cannot export power during an outage. 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
- Richmond 740 kWh a year · 138 mi
- Suffolk 740 kWh a year · 189 mi
- Alexandria 700 kWh a year · 190 mi
- Arlington 740 kWh a year · 190 mi
- Newport News 730 kWh a year · 194 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