Winter air pollution weighing on solar generation in India

From pv magazine India

Solargis, a solar data company, has said that India’s solar power generation is significantly affected by poor air quality during the winter months.

According to new data from the company, in January 2024, northern India experienced the poorest air quality in decades, with some localities facing persistent fog or smog lasting up to 20 days.

The maps show that high aerosol levels are having a direct impact on the performance of solar projects in the region. Solargis’ monthly Global Horizontal Irradiance (GHI) map for January 2024 shows substantial drops in solar irradiance – between 30% and 50% – compared to long-term averages. This continues a longer-term trend of winter underperformance in northern India, which has seen significant dips in irradiance occur in each of the last five winters.

“January 2024 saw records broken for both the lowest average monthly temperature and lowest GHI,” said Avik Mitra, business account manager at Solargis. “This had tangible impacts on the financial performance of solar projects across Punjab, Haryana, and Uttar Pradesh, which collectively host around 5 GW of installed capacity. But this has not been an isolated event.”

In addition to this recurring pattern of winter underperformance in the north, operators in central India have faced a long-term trend of below-average irradiance, stretching back over the past six years. Solargis’ 2023 Indian solar performance maps show a dip of between 1% and 5% compared to the average across central India – attributed in part to the prolonged monsoon season.

To help the industry better understand and mitigate the impact of these resource challenges, Solargis is working with a number of leading PV companies in India and providing them with irradiance data to pinpoint and address underperformance.

“We’ve grappled with identifying the root causes of underperformance for our projects in India and recognized the need for accurate yield information,” said Chris Brosz, head of engineering at Candi Solar. “Relying on robust and high-quality data has enabled us to optimize our project performance and build a scalable platform.”

Indian solar developers are investing in higher quality data to understand long-term irradiance trends and the future performance of increasingly complex renewable energy assets. The Indian market has moved from 100% solar tenders to hybrid tenders incorporating both battery energy storage and wind energy, which necessitates a better understanding of how performance is influenced by changing weather patterns.

“Often these hybrid tenders require matching generation profiles with load profiles, and there are penalties for not doing so,” said Mitra. “This has increased the need for developers to better grasp solar variability – both at intra-day and seasonal levels – and diversify their portfolios to manage financial risk.”