Cyclones' record rain in May cloud India's solar power generation

Record rainfall in May, courtesy Cyclone Tauktae and Yaas, made an unlikely impact on the production of solar power in key high-generation states of Gujarat, Rajasthan, Madhya Pradesh, and Karnataka.

As the number of cloudy days increased in April and May, solar power generation fell in the range of 7-15 per cent over the last year in these states. With untimely rains linked to climate change, sector experts feel climate variations should now be accounted for in the planning of solar power generation. 

The India Meteorological Department (IMD) said May received the second-highest rainfall in the last 120 years. Two back-to-back cyclones — Tauktae on the coast of Gujarat in mid-May and Yaas in the Bay of Bengal towards the end of the month —caused heavy rainfall in the west, northwest, and eastern India. IMD said there were western disturbances in May as well which also contributed to more than normal rainfall.

The highest solar generation loss was faced by Karnataka, which saw it declining by 15 per cent over last year, according to the data collated by ReConnect Energy, a Bengaluru-based leading ‘energy management services’ company.

Cyclone Tauktae wreaked havoc on the coasts of the state, leading to heavy rains for weeks. The monsoon also arrived in the first week of June due to the impact of Cyclone Yaas. Karnataka leads the pack in solar power installed capacity of 7 Gw.

Rajasthan, which has one of the highest solar power potentials, saw solar generation falling by 6.18 per cent in May over 2020 and 7 per cent over 2019. In Gujarat, which was in the first line of impact of Cyclone Tauktae, the decline in solar generation was similar. India’s leading solar power generators such as Adani Green, Hero Future Energies, ReNew Power, and ACME Solar have their plants in these two states. 

Rajasthan, along with Madhya Pradesh, houses India’s two largest solar power parks — Bhadla and Rewa, respectively. In Madhya Pradesh, the solar power generation fall was similar to Rajasthan. From 2019, the fall is higher by 13 per cent in 2021. 

Asim Ahmed, head of engineering, REConnect Energy, said: “Generation patterns are changing due to variability in weather patterns and climate.  The decline in generation in May could potentially be offset by an earlier end to the monsoon period. So, while generation might balance out, the solar power producers would need to take the changing pattern into account.” 

The change in generation also impacts the monthly payment to the solar power producers. The investors need to change their stance on the sector, Ahmed said.

“Investors looking at solar from a yearly fixed income point of view may need to reconsider their estimates due to the extreme weather and climate variability. It is not guaranteed that there will be similar income every year just based on the fact that Indian regions have 300 sunny days. A projection of over 25 years is subject to change due to climate-related impacts and the degree of such changes need to be investigated,” he said. 

Navdeep Dahiya, founder and chief executive of Live Weather of India, said these sudden changes were not seasonal variations anymore, this was an impact of climate change.

“Most of the weather patterns are getting delayed, especially this year. During May, which is the core summer month for Gujarat, Rajasthan saw the unusual event of maximum temperature dipping below the climatological normal by 10 to 15° due to rains and more cloudy days due to cyclone Tauktae. Such a weather event has no precedence,” he said. In 2020, wind energy generation fell by 16 per cent during its peak generation season. In July 2020, which is the highest wind generation month of the year, the yearly fall was as much as 40 per cent in some regions, this paper had reported.