Increased emissions threaten solar infrastructure in India: Study

India’s solar energy infrastructure, particularly in the southern, central and eastern regions, faces significant risks from increased greenhouse gas emissions, according to a new study published in the journal Energy and Climate Change.

Under intermediate and high emission scenarios, surface solar radiation (SSR) could see a pronounced reduction of up to 10 per cent, particularly over central, southern and eastern India, the study warned. SSR is the sun’s shortwave radiation that reaches the Earth's surface and is crucial for long-term renewable energy planning.

Solar energy is highly sensitive to meteorological conditions and long-term climate variability. The study explains that even slight variations in future can significantly impact how much of solar energy can be derived as output.

Given that solar photovoltaic panels last 20-25 years, solar developers should account for projections of how solar resources might evolve in the future with climate change, read the study.

“Our results suggest that solar developers need to look beyond annual averages and consider regional and temporal variability in solar radiation,” Ashwin Jadhav, doctoral researcher at the department of atmospheric and space sciences, Savitribai Phule Pune University, told Down To Earth. For example, he added that North-western India shows relatively stable high potential, making it more reliable for long-term investments, while parts of eastern and southern India exhibit higher variability, where hybrid systems, combining solar and wind or storage integration, may be more effective.

“Developers should also consider the projected long-term decline or stagnation in solar availability in some regions when planning the lifespan of solar photovoltaic farms (20-25 years),” he explained.

As on August 31, 2025, India’s installed capacity of solar power is 123,130.13 megawatts (MW), of which close to 14 per cent (33,674.76 MW) comes from the five southern states, showed data from the Union Ministry of New & Renewable Energy. However, the country’s solar generation as on July 2025 was 12,100.61 MW.

An earlier analysis by Climate Analytics, a global climate science and policy institute, highlighted a gap between solar capacity and generation in India, adding that weather factors were also contributing to this.

It noted that renewables made up 37 per cent of India’s installed generation capacity. However, they contributed only about 18 per cent to the electricity generated. 

“Meteorological factors like cloud cover, aerosols and extreme weather events are already influencing the solar potential that can be realised on the ground,” Jadhav explained, adding that research done by him and others have shown that our planet has gone through periods of both “global dimming” (a decrease in surface solar radiation linked to higher aerosol levels and cloud variability) and “brightening” (a recovery associated with improved atmospheric conditions) historically.

While other factors, including grid, storage and variability in supply, contribute to the capacity and generation in India, weather variability and long-term atmospheric changes are indeed significant contributors, he noted.

Future projections

Previous studies have projected impacts on SSR due to climate warming. For example, one study found a general decrease worldwide during 2006-2049, barring Europe and East Asia where reduced cloud cover and aerosols could increase solar radiation. Another study predicted a 7 per cent reduction in solar output in parts of Africa due to enhanced monsoonal activity.

Jadhav’s study explained that few studies have assessed the future potential of solar energy over India under climate change scenarios.

The new study predicted future trends projected for three emission scenarios — low, intermediate and high — for three future periods: Near future (2021-2040), mid future (2041-2060) and far future (2081-2100).

Their analysis showed that in a low emission scenario, most parts of India might see slight reductions in SSR, ranging between 0.5 per cent and 1 per cent per decade, particularly over the southern and western parts of the country.

Conversely, isolated areas in the Indo-Gangetic Plains and northeastern states might see some marginal increases, likely due to reductions in aerosol concentrations and changes in cloud dynamics.

In an intermediate emission scenario, most of India, including central, southern, and northeastern regions, is expected to see reductions in solar radiation ranging from 0.5 per cent to more than 1 per cent per decade. This translates to a mean SSR loss of 1.10 watts per square metre per decade over India.

Under a high emission scenario, the whole Indian subcontinent is likely to be affected, with reduction exceeding 1 per cent per decade in majority of the country, and particularly severe decrease over central, western and peninsular India. This translates to a mean SSR reduction of upto 1.32 watts per square metre per decade over India.

The intermediate and high emission scenarios, according to the study, warrant the urgent need for adaptation measures such as targeted solar park deployment, advanced forecasting systems and climate-resilient solar technologies.

The study linked these reductions largely to increased atmospheric turbidity and enhanced post-monsoonal cloud cover, which, the researchers wrote, directly threaten solar power generation potential in India’s key renewable energy zones.

The paper also called for promoting the development and adoption of advanced forecasting systems that incorporate cloud-level and aerosol data to help improve the accuracy of SSR. Going forward, Jadhav hopes to further analyse seasonal and extreme event analysis to understand how monsoon cloud variability or increasing extreme weather events could impact solar generation reliability. He also hopes to link climate projections with real-world photovoltaic performance and grid models.