Solar & Battery Sizing for Johannesburg, South Africa
⚡ Sizing for a different location?
This page is a benchmark reference for Johannesburg. The BigEnergyCo calculator works for any location worldwide using your exact coordinates.
⚡ Size Any Location Worldwide →The short answer: Johannesburg sits at 26.20° S, 28.05° E — subtropical latitude. This page's 1400–1800 kWh per kWp per year band is a rough latitude-only estimate with unknown source grade, not a local measurement or forecast. For location-specific weather input, the calculator uses five years of hourly NASA POWER data. See the estimate's provenance.
What the calculator does for Johannesburg
Type "Johannesburg" (or use your exact GPS coordinates) into the estimator and it will:
- Simulate five years of hourly NASA satellite weather for your location — not a yearly average, the actual hourly series including bad weeks.
- Size grid-tie bill-cutting systems at 60%, 80%, and 95% targets, with payback from your own tariff.
- Size fully off-grid systems at three reliability tiers — from "never needs a generator" to "a few generator hours a year".
- Compare battery chemistries by true lifetime cost: LiFePO4, sodium-ion, and lead-acid including replacement cadence.
- Produce a hardware parts list with panel count, bank configuration, inverter class, and cable gauges, exportable as CSV.
Worked example: a 10 kWh/day household
This static example uses the unsourced latitude-only yield band above and a fixed 1.5× dark-week margin. Treat the panel range as an illustration, not a forecast or sizing recommendation. The battery column is re-sized by the simulator against your location's darkest week, so its result can differ from this static band:
| Bill cut | Typical panels | Typical battery |
|---|---|---|
| ~60% | 1.5–2.5 kW | 3–5 kWh |
| ~80% | 2–3.5 kW | 4–7 kWh |
| ~95% | 2.5–4 kW | 5–9 kWh |
Every money figure here is in US dollars; the calculator converts to your own currency. Payback depends on your local tariff: at ~$0.18/kWh a 60% cut on this load saves roughly $394/year, which repays landed-DIY component costs (about $1,614) in about 4.1 years. Where power is cheap, payback stretches — the tool shows your personal number from your own rate.
Why simulate instead of estimate?
Latitude bands cannot capture local clouds, roof shade, or orientation. The five-year hourly weather simulation models seasonal conditions and the darkest week, but it is still an estimate rather than a roof survey.
Run the Johannesburg simulation now. Free, no signup, nothing for sale. Every number computed in your browser from real satellite weather.
⚡ Size my Johannesburg systemOther cities
Browse all 66 benchmark cities →
Related guides
- How to cut your electricity bill with solar (honest math)
- Is a home battery worth it?
- Off-grid vs grid-tied: which pays back faster?
- What size solar system for off-grid?
- About the method (NASA weather, derates, update cadence)
Frequently asked
How much solar do I need in Johannesburg?
It depends on your daily kWh use and roof conditions. The static latitude band on this page has unknown source grade and is not a local production forecast. The free calculator estimates production from five years of hourly NASA POWER weather at your coordinates.
Does solar work in South Africa?
Latitude alone cannot predict output at a specific roof. Local weather, shade, orientation, and installation matter; the calculator uses hourly weather data to estimate location-specific sizing.
Is the Johannesburg solar calculator free?
Completely. No signup, no email, nothing for sale. You type your city or coordinates, enter your bill or daily usage, and get off-grid tiers, bill-cut scenarios, payback, and a hardware parts list — all computed in your browser.