New Study: Rooftop Solar's Climate Benefits Vastly Underestimated

Cutting-edge research suggests that global rooftop solar could reduce warming by up to 0.13 °C by 2050—a game-changer for climate targets.

In a new study published in Nature Climate Change, researchers have estimated that rooftop photovoltaic systems (RPVs)—long seen as marginal in global climate strategies—actually hold immense potential to curb warming. 

The research team scanned high-resolution AI-derived rooftop maps and nine state-of-the-art Earth system models (CMIP6), arriving at the contention that fully deploying rooftop solar worldwide could shave 0.05–0.13 °C off global temperatures by 2050, significantly aiding the goal of limiting warming to 1.5 °C 

A Deeper Dive Into the Data

The study began with a global mapping mission. Using AI-enhanced remote sensing, researchers identified 286,393 km² of rooftop area—total square footage somewhere between the size of the UK and Italy. This granular data gave researchers the baseline needed to make projections of how much solar infrastructure the world’s rooftops might support

Integrating rooftop solar deployment into industry-standard climate simulations reveals that widespread RPV systems can trim warming by 0.05–0.13 °C by mid-century Here are a few key takeaways from the report:

• Earth has already warmed about 1.2 °C since pre-industrial times.
• That leaves us only 0.3 °C of “wiggle room” before hitting the 1.5 °C danger zone.
• If rooftop solar (RPVs) were rolled out at global scale, they could reduce future warming by 0.05 to 0.13 °C.
• That reduction gives us back 17% to 43% of the remaining “safe” climate space (0.3 °C)—which is part of that wiggle room mentioned above.

Regions and Tipping Points

The benefits aren’t evenly distributed. Regions rich in solar irradiance, with dense rooftops, and high-carbon electricity grids would have the greatest impact. Africa, Asia, and parts of North America and Europe, for instance, have a high mitigation potential per unit of installed solar.

In contrast, regions rapidly greening their grids see diminishing incremental gains from rooftop solar—emphasizing the need for strategic, location-specific deployment. In addition, one could expect variations in individual roofs, based on shading, compass facing and so on. 

One of the study’s most striking insights: rooftop solar could delay climate tipping points, such as the collapse of the Atlantic Meridional Overturning Circulation, by approximately 25–66%. Similar improvements were found for Arctic ice loss and mountain glacier retreat. These small degrees matter immensely when Earth systems respond non-linearly near critical thresholds.

3 Ways Rooftop Solar Offsets CO2

1. Direct emissions offset
   RPVs replace fossil-fuel electricity right at the load point, offering immediate CO₂ reductions.
2. Surface temperature effects
   Solar panels absorb sunlight and in some cases reflect less heat than rooftops, modestly cooling the local environment—a subtle but measurable benefit. They also may extend the lifespan of asphalt or rubberized roofing under extreme heat conditions.
3. Grid resilience and decentralization
   Distributed rooftop power helps balance demand peaks and reduce transmission losses, contributing to less carbon-intensive power overall.

How Could this Scenario Be Realized?

To unlock this overlooked climate powerhouse, Zhang et al. recommend:

• Targeted rollout in high-potential regions—where sunlight, rooftop density, and dirty grids align.
• Grid upgrades and storage integration to manage solar variability.
• Incentives and equitable access to rooftop solar across urban and low-income communities.
• Engaging citizens as prosumers—turning energy consumers into energy producers to multiply benefits.

A Vital But Underestimated Weapon

Until now, rooftop solar has often been sidelined in favor of utility-scale renewables and grid modernization. That perception needs an overhaul. This study proves that RPVs can be a significant ally in the climate fight.

Full Article Link:
Zhang, Z. et al. (2025). Worldwide rooftop photovoltaic electricity generation may mitigate global warming. Nature Climate Change, 15, 393–402. https://www.nature.com/articles/s41558-025-02276-3