Balcony solar in San Jose

800 W of panels on a south-facing balcony railing in San Jose produce about 830 kWh a year and save about $141.

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°
East600 kWh1,070 kWh
South-east790 kWh1,260 kWh
South830 kWh1,350 kWh
South-west830 kWh1,290 kWh
West660 kWh1,120 kWh

Output by month

Railing (vertical) Tilted at 30°
Monthly output in San Jose, south-facing0100200JanFebMarAprMayJunJulAugSepOctNovDec
Show as a table
MonthRailing (vertical)Tilted at 30°
Jan92 kWh87 kWh
Feb79 kWh88 kWh
Mar75 kWh110 kWh
Apr66 kWh130 kWh
May48 kWh140 kWh
Jun35 kWh130 kWh
Jul41 kWh140 kWh
Aug59 kWh140 kWh
Sep71 kWh110 kWh
Oct94 kWh110 kWh
Nov86 kWh86 kWh
Dec86 kWh79 kWh

Savings and payback

At $0.3258 per kWh you save about $141 in the first year. A kit costing $1,300 pays back in about 9.2 years.

  • Electricity price: $0.3258 per kWh (U.S. Energy Information Administration, 2025-09..2026-08). Source
  • Assumes a constant base load of 150 W, so 52% of the output is used at home.
  • Power sent to the grid is not paid for.

Calculate with your own figures

Rules

California

Takes effect on January 1, 2027

Up to 1,200 W of inverter output per home.

  • Certified as a plug-in photovoltaic system by UL or an equivalent nationally recognized testing laboratory, with a certified feature that prevents backfeeding during an outage; meets the National Electrical Code and the California Electrical Code.
  • Your utility may ask you to register the kit.

Last verified: October 31, 2026

Full rules for California

Nearby cities

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