Experts from the India Meteorological Department (IMD) have conducted a recent study that has revealed an unsettling trend: a reduction in solar radiation over a large portion of the nation, leading to a reduction in the potential for producing solar electricity across the board. Published in the IMD's scientific journal Mausam, the study titled “Understanding the climatology and long-term trends in solar radiation using ground-based in-situ observations in India” highlights the need for more efficient equipment to tackle this situation effectively.
The study, authored jointly by six scientists, analyzed data from 13 IMD stations with continuous solar radiation records spanning from 1985 to 2019. These stations were chosen for their reliability and extensive data availability over the years. The investigation focused on various parameters such as global radiation (GR), diffuse radiation (DR), bright sunshine hours (BHS), and the technical potential of solar photovoltaic power (SPV).
While India holds vast SPV potential ranging from 1800 to 3400 Wm-2, regional variations are substantial. The study highlights the importance of understanding these variations for optimal utilization of solar energy in power generation, which requires accurate information on solar radiation and its trends.
One of the key findings of the study is the significant reduction in GR across most parts of the country, attributed to increased atmospheric turbidity and cloudiness. Conversely, there has been a notable increase in DR in over 50 percent of the stations, particularly in the northwest and certain parts of peninsular India. This increase is also linked to heightened atmospheric turbidity and cloudiness.
Although the declining trend of average GR has slowed down in the recent decade, the rate of increase in average DR has accelerated during the same period. Additionally, the study highlights a significant decrease in BHS in 75 percent of the selected stations, with variations observed across different regions and seasons.
The presence of aerosols in the atmosphere, originating from sources such as industrial emissions, vehicle exhaust, and biomass burning, has been identified as a contributing factor to the decrease in solar radiation. These aerosols have the capacity to absorb and scatter sunlight, thereby reducing the amount of solar radiation reaching the Earth's surface.
Furthermore, the study underlines the importance of solar radiation in governing the earth’s surface-atmosphere energy exchange and climate. Solar energy plays a crucial role in moderating the global energy balance and influencing climate patterns, highlighting the significance of addressing the declining trend in solar power generation potential.
India's ambitious targets to increase renewable energy capacity to 500 GW by 2030 face significant challenges in light of the observed decline in solar radiation. Regions heavily reliant on solar power, such as Gujarat and Rajasthan, are particularly vulnerable to these challenges.
Despite these hurdles, solar energy remains a promising alternative to conventional energy resources, offering a means to mitigate greenhouse gas emissions and reduce global warming. Moreover, it presents an opportunity for self-reliant energy generation, reducing dependence on foreign energy sources.
The study underscores the urgent need for adopting more efficient solar panels to mitigate the impact of decreasing solar power generation potential in India. Addressing this issue is crucial not only for meeting the country's energy needs but also for advancing its sustainable development goals in the long run.
