A recent study from Potsdam Institute for Climate Impact Research [52.4°N, 13.0°E] and Mälardalen University [59.6°N, 16.5°E] has revealed an astonishing truth: rooftop solar panels alone could generate two-thirds of the world’s electricity needs.
By mapping rooftops at a high-resolution global scale using artificial intelligence, the researchers estimated that 286,393 km² of rooftop space is available worldwide. If fitted with photovoltaic (PV) panels, these surfaces could produce 19,483 terawatt-hours (TWh) of electricity per year — enough for much of our electricity, while dramatically cutting carbon emissions.
Why Rooftop Solar is a Game-Changer
Solar power is often thought of in terms of large solar farms — vast arrays of panels stretching across open landscapes. But this study highlights the untapped potential of rooftops, offering several advantages:
✔ No extra land use: Rooftop solar avoids the land conflicts that come with large-scale solar farms.
✔ Faster implementation: Unlike new power plants, which require major infrastructure, rooftop panels can be installed on existing buildings.
✔ Lower transmission losses: Generating power where it’s used reduces the inefficiencies of transporting electricity over long distances.
✔ Massive carbon savings: Replacing fossil fuels with rooftop solar could reduce global temperatures by up to 0.13°C before 2050.
Key Findings: Where Rooftop Solar Works Best
The study found that rooftop solar potential varies widely across regions:
- 🌍 High solar radiation but low building density: Africa has some of the best solar conditions, yet limited rooftop availability means its potential accounts for just 7% of the world total.
- 🌆 High building density but moderate solar conditions: Europe and North America receive less sunlight than Africa, but their urban rooftops provide a much larger installation potential. Combined, these regions could install 4,339 GW of solar capacity—a quarter of the global total.
- 🌞 Solar intensity meets urban expansion: China, India, and Southeast Asia have both strong sunlight and rapid urbanisation, making them some of the most promising regions for rooftop solar growth.
Could Rooftop Solar Make a Real Difference?
Absolutely. The research found that solar rooftops could help prevent the Earth from passing key climate tipping points. The study mapped out nine future climate scenarios, showing that:
- If rooftop solar is fully deployed, global temperature rise could be reduced by 0.05–0.13°C by 2050.
- This could contribute up to 43% of the effort needed to stay below the 1.5°C global warming limit set by the Paris Agreement.
In places like Northern Europe and North America, where energy grids still rely on fossil fuels, rooftop solar could make an especially big impact by cutting carbon emissions from electricity production.
A Future Powered by Rooftop Solar
The vision is clear: instead of relying on fossil fuels or distant power plants, cities could become self-sustaining energy hubs, with every rooftop acting as a miniature power station.
This study suggests that rooftop PV could play a central role in a clean energy future with the right policies in place;
- investment in rooftop solar
- better grid integration
- storage solutions
The only question now is: how soon will we make it happen?
Source
Worldwide Rooftop Photovoltaic Electricity Generation May Mitigate Global Warming, Nature Climate Change, 2025-03-07
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