What this map shows
The colours show PV power potential (PVOUT) from the World Bank’s Global Solar Atlas: how many kilowatt-hours a typical 1 kWp solar installation (roughly three modern panels) produces per day, averaged over a long-term record of satellite-derived weather. Deep purple marks the least productive regions (cloudy, high-latitude), bright yellow the best deserts. Hover anywhere to read the exact value and its annual equivalent; click to get a popup with a link to our solar panel calculator, already set to that location and its best tilt.
How to read the numbers
Multiply the annual figure by your system size. A 6 kWp rooftop system where the map shows 3.8 kWh/kWp/day (about 1,390 kWh/kWp per year) will produce roughly 8,300 kWh per year. Because the atlas assumes an optimally tilted, unshaded array with typical losses, real rooftops facing east or west, or partly shaded, usually produce 5–20% less.
| kWh/kWp per day | per year | Typical places |
|---|---|---|
| 2.3–2.8 | 850–1,000 | Scotland, Ireland, Denmark, southern Chile, Pacific Northwest |
| 2.8–3.4 | 1,000–1,250 | Germany, Poland, Benelux, Northern France, Japan |
| 3.4–4.2 | 1,250–1,550 | Spain (north), Italy, Romania, Turkey, Eastern USA, China (east) |
| 4.2–5.0 | 1,550–1,800 | Southern Spain, Greece, California, South Africa, India, Brazil (north-east) |
| 5.0–6.6 | 1,800–2,400 | Atacama, Namibia, Sahara, Arabia, Arizona, central Australia, Tibet |
Why the map looks the way it does
Latitude matters less than clouds. Equatorial rainforests (Congo Basin, Amazon, Indonesia) are surprisingly modest because of persistent convective cloud, while subtropical deserts under high-pressure belts at 20–30° north and south are the brightest. Altitude helps: thinner, drier air lets more sunlight through, which is why the Andes, the Ethiopian Highlands and the Tibetan Plateau stand out. Heat hurts slightly: PV cells lose roughly 0.3–0.4% of output per °C above 25 °C, so the hottest lowland deserts score a little below cooler high plateaus with the same sunshine. Sichuan and Chongqing in China form one of the darkest patches on Earth due to near-permanent haze and cloud.
From resource to project
A good resource is only part of the story: electricity prices, financing costs and installation prices decide whether solar pays. Our calculators turn the resource into money. The solar panel calculator runs an hourly simulation with real NASA weather for your location, the how-many-panels calculator sizes a system to your consumption, and the solar battery calculator shows how much self-consumption a battery adds. To see what every country already gets from solar, play the solar share time-lapse; to find individual solar parks, open the solar & wind farms atlas.
Data and licence
Source: Global Solar Atlas 2.0, a free, web-based application developed and operated by Solargis on behalf of the World Bank Group, funded by ESMAP. Data © 2019 The World Bank, Solargis, licensed CC BY 4.0. We recoloured the long-term average PVOUT layer, resampled it to Web Mercator tiles (about 4 km at maximum zoom) and quantised it for hover read-outs; values are therefore approximate. Coverage ends at 60°S and 65°N, so northern Scandinavia, Iceland and Alaska are not shown.