Climate projections for 2021–2050 for Karnataka show that the summer maximum temperature is projected to increase by 1.4 to 2.4 degrees Celsius in the districts with thermal power plants, and by 1.7 to 2.4°C in districts with solar power plants. The mean annual rainfall is projected to increase by 11% to 22% in the districts with power infrastructure, and heavy rainfall events by two to six events in districts with thermal power plants and by one to two events in some of the districts with solar power plants.
For a State that has often battled with allegations of unreliable power supply infrastructure, what will this mean? And what are the challenges that the new push for renewable energy such as solar power faces with regard to climate change?
The ‘Climate Risk Profile for Power Sector in Karnataka’ by the Centre for Study of Science, Technology and Policy (CSTEP), brought out this March taking into account maximum temperature, heavy rainfall events, and vulnerability criteria, indicates that thermal power plants in Vijayapura are at “medium-high” risk, those in Raichur and Ballari are at “medium” risk, and the Udupi plant is at “very low” risk. Solar power plants in all the eight districts fall in the “low-medium” risk category.
The implications of an increase in temperature and shortage of water include a 0.3% to 0.5% reduction in solar efficiency and material damage, a 0.4% to 0.7% reduction in thermal efficiency, and reduced transmission efficiency because of additional resistance and increased conductor sag. On the other hand, the implications of an increase in heavy rainfall events are 30% reduction in solar efficiency because of dark rain clouds and material damage, and reduced boiler efficiency because of increased moisture content of coal and delay in coal supply as Karnataka’s thermal plants rely on inter-State supply, the report adds.
Speaking to The Hindu, Indu K. Murthy, Principal Research Scientist, Domain Lead-Adaptation and Risk Analysis team at CSTEP, and one of the key authors of the report, said the idea of the study stemmed from the fact that not much attention is given to the power sector in India while rest of the world is looking at the risk factor. “We have been hearing about more and more extreme events. According to the Ministry of Earth Sciences report, there will be more such extreme events till the end of the century. All infrastructure has been designed with historical climate in mind. It makes sense to look at what will happen in the future to design and maintain infrastructure. An initial climate change risk assessment is important for practitioners to make decisions and climate-proof infrastructure,” she said.
The researchers started off with climate hazard mapping, looking at historical climate data and compared data with the future period. “What we see for districts in Karnataka with thermal and solar power plants is that there will be an increase in temperature over a 30-year period, and though the increase looks small it will not be a smooth curve,” Ms. Murthy explained.
Furthermore, heavy rainfall events will also increase in the future. In certain districts with solar plants, such as Bagalkot and Chitradurga, no such events have been recorded historically. So the projected extreme rainfall events could become the new normal, she pointed out.
So what is the way forward? The researchers suggest a multi-pronged approach involving technological interventions such as promoting better designs and improved standards, planning-related measures such as mapping climate hazards and risks to help formulate strategies for exposure reduction, investing in resilient infrastructure and increasing share of renewables, prioritising projects and designs that are adaptable to future climate conditions, and budgetary allocation for periodic review, repair, and upgrade to reduce climate vulnerability.
They have also recommended development of a resilience index with a minimum acceptable standard for periodic review of existing infrastructure, drafting of a retrofit code, and imposing legal liability to adhere to standards, legislation for adoption of green infrastructure or a hybrid approach, and development of a compendium of resilient technologies through the creation of a technological consortium for research, development, and innovation.