Study says solar radiation available for producing power falling in India
The quantity of solar radiation available that can be economically converted by solar panels to electricity is showing an “alarming decreasing trend” in several locations in India, says an analysis by scientists at the India Meteorological Department (IMD) and published this month in the organisation’s in-house scientic journal Mausam.
While increased aerosol load — ne particles from carbon emissions, fossil fuel burning and dust — and clouding are said to be causative factors, installing more ecient solar panels could help counter this, the scientists say in their paper.
Aerosols absorb the sunlight and de£ect it away from the ground and they can also precipitate the formation of dense clouds that again block sunlight. The eciency of solar panels are signicantly in£uenced by the amount of sunlight falling on them.
For the study, the scientists looked at radiation trends at 45 in-house stations, which have instruments to measure solar radiation but used data from only 13 to compute the changes in solar photovoltaic (SPV) potential as they were the only ones with a continuous record from 1985 to 2019. SPV is the amount of radiation that may be practically available to be converted to electricity by panels.
SPV potential showed a general decline in all stations which included Ahmedabad, Chennai, Goa, Jodhpur, Kolkata, Mumbai, Nagpur, New Delhi, Pune, Shillong, Thiruvananthapuram,
Vishakhapatnam.
India’s largest solar parks are located in the north-west of the country, particularly Gujarat and Rajasthan, and cities in both these States are also showing a decrease in SPV potential. As of today, India’s installed solar power capacity is about 81 GW (1 GW is 1,000 megawatt), or roughly 17% of the total installed electricity.
India has ambitious plans of sourcing about 500 GW, nearly half its requirement of electricity, from non-fossil fuel sources by 2030. This would mean at least 280 GW from and solar power by that year or at least 40 GW of solar capacity being annually added until 2030. In the last ve years, this has barely crossed 13 GW though the government has claimed that COVID-19 aected this trajectory and the country was on track to add between 25-40 GW annually in the coming years.
Prime Minister Narendra Modi had earlier this year also announced a major initiative to fund rooftop solar installation in at least one crore houses across the country.
While the role of aerosols in blocking sunlight available on earth has been apparent since the 1980s, several studies have shown that there are variations both over time and location.
Global solar radiation showed a generally decreasing trend from 19812006. 1971-2000 showed greater dimming compared to 1981-2006. However, on the whole, there was a reversal in trends after 2001 with the exact causes unclear.