How much does balcony solar actually save in California?
By Mike YuPublished September 1, 2026
The formula, once
Everything on this page comes from one line:
annual saving = sun × size × direction × tilt × shade × how much you use × your rate
That's it. There's no financing structure, no depreciation schedule, no tax treatment. It's arithmetic, and you can check ours.
The inputs
Sun. In Orange County, a kilowatt of panel at optimal tilt produces about 1,586 kilowatt-hours a year, per NREL's PVWatts data.
Direction. South 1.00, west 0.83, east 0.80, north 0.35.
Tilt. Angled toward the sun 1.00, flat 0.88, vertical on a railing 0.62.
Shade. Open sky 1.00, partly blocked 0.75, mostly blocked 0.45.
How much you use. Someone home most days 75 percent, sometimes 62 percent, empty by day 45 percent, business 90 percent, or up to 90 percent with a battery.
Your rate. SCE 33.2 cents including the Climate Credit as of 1 June 2026. SDG&E about 45.7 cents. PG&E about 39.25 cents.
Exported power: zero. SB 868 provides no compensation for what you send back.
Nine worked examples
| # | Setup | Working | Annual saving |
|---|---|---|---|
| 1 | 360W, west, railing, open, someone home, SCE | 1,586 × 0.36 × 0.83 × 0.62 × 1.0 × 0.75 × 0.332 | $73 |
| 2 | Same, with tilt bracket | 1,586 × 0.36 × 0.83 × 1.0 × 1.0 × 0.75 × 0.332 | $118 |
| 3 | 800W, west, tilted, open, someone home, SCE | 1,586 × 0.8 × 0.83 × 1.0 × 1.0 × 0.75 × 0.332 | $262 |
| 4 | 800W, west, tilted, open, empty by day, SCE | same × 0.45 instead of 0.75 | $157 |
| 5 | 1,200W, south, tilted, open, someone home, SCE | 1,586 × 1.2 × 1.0 × 1.0 × 1.0 × 0.75 × 0.332 | $474 |
| 6 | Same, but partly shaded | 1,586 × 1.2 × 1.0 × 1.0 × 0.75 × 0.75 × 0.332 | $355 |
| 7 | 1,200W, north, tilted, open, someone home, SCE | 1,586 × 1.2 × 0.35 × 1.0 × 1.0 × 0.75 × 0.332 | $166 |
| 8 | 1,200W, south, tilted, open, someone home, SDG&E | rate 0.457 instead of 0.332 | $652 |
| 9 | 800W, south, tilted, open, café open daytime, SCE | self-consumption 0.90 | $379 |
Look at rows 1 and 2. A $60 tilt bracket added $45 a year — it pays for itself in sixteen months and it's the single best purchase in this category.
Look at rows 3 and 4. The same equipment, same balcony, same city. The only difference is whether anyone's home. That's a 40 percent swing, and no product page will ever mention it.
Look at rows 5 and 8. Same everything except the utility. SDG&E customers get 38 percent more from an identical panel, because their electricity costs more.
What about payback?
| Setup | Kit cost | Annual saving | Simple payback |
|---|---|---|---|
| 360W starter, west railing | $414 | $73 | 5.7 years |
| Same plus tilt bracket | $474 | $118 | 4.0 years |
| 800W, tilted, someone home | $850 | $262 | 3.2 years |
| 1,200W, south, tilted | $1,300 | $474 | 2.7 years |
| 1,200W plus 1.9 kWh battery | $2,200 | $564 | 3.9 years |
| 1,200W, north-facing | $1,300 | $166 | 7.8 years |
Panels typically carry 25-year warranties. Microinverters are usually warranted 10 to 12 years, which is the number that actually constrains the lifetime economics — budget for replacing one at some point.
What we're not counting
Rate increases. California electricity prices have risen substantially and steadily. We hold the rate flat, which makes every figure here conservative. If SCE's rate rises 4 percent a year, a $262 saving is $318 in year five.
Degradation. Panels lose about half a percent of output a year. Over a decade that's a 5 percent haircut. Small next to the rate increases going the other way.
Any tax credit. There isn't one. The federal 30 percent credit ended for expenditures after 31 December 2025.
The fixed charge. SCE's Base Services Charge, around $24.15 a month for non-CARE customers, doesn't move regardless of how little you buy. Solar reduces the usage part of your bill only.
The honest framing
A maxed-out 1,200-watt system covers something like 13 to 21 percent of a typical California home's annual electricity. It's a bill trimmer, not a bill killer.
That's not a criticism. A $400 saving a year on a $900 purchase is a better return than most things you can buy, and it repeats for twenty years. But if you're expecting your bill to halve, you've been reading somebody else's marketing.
Get the figure for your own place → · How the model works →
Sources
Every legal, numeric and safety claim on this page traces to one of these.
- NREL PVWatts Calculator — accessed September 1, 2026
- SCE Rate Advisory, June 2026 — accessed September 1, 2026