Solar power potential in India declining alarmingly, need for remedial measures: IMD study

Vijay Mohan

Chandigarh, April 11

A study undertaken by experts from the India Meteorological Department (IMD) has revealed a significantly decreasing trend in solar power generation potential in the country and has suggested use of more efficient equipment to deal with the situation.

“There is an alarming decreasing trend in the solar photovoltaic potential in all the selected stations which is likely to continue in the near future as well. It would negatively impact energy production from solar resources,” it states.

The study titled “Understanding the climatology and long-term trends in solar radiation using ground based in-situ observations in India,” authored jointly by six scientists, has been published by IMD in April.

The authors investigated the climatology and trends of global radiation (GR), diffuse radiation (DR), bright sunshine hours (BHS) and technical potential of solar photovoltaic power (SPV) using data procured from IMD for the period 1985–2019.

The country has vast SPV potential, in the range of 1800–3400 Wm-2, though with substantial regional variations. Understanding the variations of solar power potential over the country is essential for the optimum utilisation of solar energy in power generation, which demands accurate information of solar radiation and its variations, the authors said.

The study points towards a significant reduction in GR in all parts of the country except the extreme northwest, where the trend is not prominent. Reduction in GR is attributed to the increased atmospheric turbidity and cloudiness.

A significant increase in DR has been observed in more than 50 percent of the stations, especially in the northwest and some parts of peninsular India, which has also been attributed to increased atmospheric turbidity and cloudiness.

While, the declining trend of the average GR over the country has been reduced in the recent decade, the rate of increase of average DR over the country has escalated in the recent decade, the authors said.

Pointing out that BHS has significantly decreased in 75 percent of the selected stations, the study brings out that the annual BHS is high in northwest India but low in north, north-east and southern peninsular India. Most of the stations exhibit maximum BHS during the pre-monsoon and minimum during the monsoon season.

Solar radiation has an important role in governing the earth’s surface-atmosphere energy exchange and climate of the Earth. It modulates global energy balance and changes the climate and hydrological cycle.

Various sectors such as agriculture, energy, industry, etc. directly or indirectly depend on the incoming solar radiation.

Solar energy has been recognized as an alternative to conventional energy resources. Amongst all the clean technologies, solar energy serves as an effective renewable energy resource to mitigate greenhouse gas emissions and reduce global warming.

Further, solar energy is one of the resources capable of self-reliant energy generation, reducing foreign energy dependence, the authors observed.

The GR over India is maximum over north-west India and inland areas of peninsular India whereas it is minimum over the extreme north and north-east India. All stations exhibit substantial monthly variations in various parameters.

“The technical potential of solar power has a significant decreasing trend in most of the selected stations which is alarming. It necessitates the wide use of solar panels with better efficiency to meet the energy requirements from solar resources,” the authors concluded.