In addition to polluting the air and warming the planet, India’s thermal power plants are consuming excessive amounts of water, in many cases beyond the permissible limits set by the environment ministry, according to information obtained through the Right to Information Act.
About 51% of 156 thermal plants across 12 states whose data could be obtained declared themselves compliant with water norms early this year, said the RTI response received by the Manthan Adhyayan Kendra, a research centre that analyses water and energy issues in India.
This excessive water consumption is causing water stress, we explain later, which affects households, farms and industries in the plant’s neighbourhood. It is also resulting in the shutting-down of the thermal plants. Up to 40% of India’s thermal plants are located in areas facing acute water shortages, according to an analysis by the World Resources Institute and are worsening the water crisis there. In this analysis, the World Resources Institute has categorised thermal power plants as those where steam is generated and water cooling is needed. This would include coal, oil, biomass and nuclear. In total, India has 399 such plants.
About 600 million Indians live with high-to-extreme water stress, while over 40% of annually available surface water is used every year, according to a 2018 study by government think-tank Niti Aayog, as IndiaSpend reported on June 25, 2018.
Up to 19% of the remaining plants declared themselves noncompliant, as per the RTI responses. The others either did not supply any data or offered insufficient information. Some plants were found shut. Also, 14 plants reported using seawater which exempts them from complying with water norms.
As of August 30, there were 269 thermal power plants in India, according to the Central Electricity Authority. Taken together, these plants consume 87.8% of the total amount of water consumed by the industrial sector, according to a study conducted by The Energy and Resources Institute. To put this in perspective, such amounts of water could fulfil the water needs of four cities for two days.
Renewable energy units cause far less water stress: Solar plants, for example, consume only a fraction of the water used by thermal plants and wind energy does not need any water at all.
The detailed RTI response and its analysis have been documented in a report released by Manthan on July 1. Manthan had sought but did not receive information from West Bengal, Karnataka and Rajasthan.
Two-way problem
Thermal power plants in India use water for cooling purposes and the disposal of fly ash, a byproduct in combustion processes.
“The usage of conventional technologies like burning coal to generate power requires large quantities of water,” said Shripad Dharmadhikary, founder of Manthan Adhyayan Kendra. “This is the first problem. Secondly, we do this [the production of thermal power] inefficiently.”
This excessive water use creates two interlinked problems: Thermal power plants affect water security and are, in turn, affected by the non-availability of water, said Shresth Tayal, a fellow with TERI. “The energy security of the country cannot be achieved without water security,” he said.
Between 2013-’17, around 61 coal plants were shut down because of water shortages, resulting in a loss of 17,000 gigawatt-hours of electricity, according to a report by the Institute for Energy Economics and Financial Analysis that conducts research and analysis on financial and economic issues related to energy and the environment. “National Thermal Power Corporation’s Super Thermal Power Plant in Farakka, West Bengal and Rihand Super Thermal Power Project in Uttar Pradesh, Parali Thermal Power Plant in Maharashtra, Raichur Thermal Power Plant in Karnataka and Ennore Thermal Power Station in Tamil Nadu are all located in water-stressed areas and have been shut-down because of water storages,” said Deepak Krishnan, manager with the energy programme at the WRI, India.
Water limits raised
Until December 2015, there were no norms to monitor water usage of thermal power plants. Then, on December 7, 2015, the Ministry of Environment Forest and Climate Change issued a notification which declared that old plants could use 3.5 cubic metres of water per megawatt-hour and those installed after January 1, 2017, could use 2.5 cubic metres of water per megawatt-hour.
In October 2017, the government eased the water consumption norms for even plants that started operations on or after January 1, 2017 – they are now allowed to consume up to 20% more water than permitted earlier. Passed as amendments to the Environment (Protection) Rules, 1986, the new rules allow plants to use up to 3 cubic metres per megawatt-hour. This additional amount is enough to irrigate 700 hectares of land a year.
The average water requirement of coal-based plants with cooling towers is about 5 cubic metres to 7 cubic metres of water per megawatt-hour, according to the NITI Aayog. “In terms of installed capacity and water consumed per megawatt-hour of electricity generated, coal plants are the biggest consumers of water among thermal plants,” Dharmadhikary explained.
Said Tayal, “There are technologies like dry cooling systems that have been employed in countries like South Africa and Australia that can be used to improve water efficiency. Plants that use this technology use as less as 0.5 cubic metres to 1 cubic metre of water per unit of electricity generated. But the point is, dry cooling reduces the efficiency of the plant in terms of electricity production. So, we have to strike a balance between electricity and water efficiency.”
Effect on communities
Efficient alternatives have become important also because thermal power plants put other water consumers – households, farming communities and other industries located in the area – at risk. There have been at least four cases where local communities were or still are in danger of losing sufficient access to water for household use or farming because of the water strain imposed by local thermal power plants or proposed thermal power plant projects in the area, as per latest data gathered by Land Conflict Watch since 2017. There are also four other cases where concerns were reported of water contamination by thermal power plants.
The rate at which thermal power plants are gulping water will only increase in the coming years, according to this World Resource Institute paper. Thermal plants and other water consumers like farms, households and other industries located in the same watershed will end up competing for the water, it predicted.
Lack of transparency
Till date, compliances – or lack thereof – with water consumption regulations are self-reported by individual power plants.
“There is no real monitoring,” Dharmadhikary said. “The State Pollution Control Boards are only receiving the data filed by the power plants.” The responsibility to monitor water consumption norms also rests on the environment ministry in the case of plants it clears, he added. “The conditions based on which the clearance was granted should be monitored by the regional offices of the ministry.”
Self-disclosures could also be made more robust to include baseline information like water consumed in the previous year. This information can be used to make comparisons with other data offered by verifiable evidence – water bills, for example – to support and substantiate the disclosures, the World Resource Institute suggested.
A more wholesome solution, though, is to switch to renewable sources of energy, as we mentioned earlier.
Solar is a water-saving alternative. Consider this: a 1-megawatt thermal plant operating at full capacity for a year would produce 8,760 MW per hour of electricity while consuming 22,688 cubic metres of water [assumption or 2.59 cubic metres of water per megawatt-hour], explained Krishnan. But five solar plants of 1-megawatt capacity each, operating at 20% capacity utilisation factor, would consume 876 cubic metres of water per megawatt-hour to produce 8,760 MW per hour of electricity.
“Compared to cooling technology advancement or plant efficiency enhancement, transitioning to more solar photovoltaic [technology to convert sunlight into electricity by using semiconductors] and wind generation is the only pathway at scale that can cut back both water withdrawal and consumption while sustaining growth in power generation,” a World Resource Institute report stated last year.
We emailed and telephoned the environment ministry and the Central Pollution Control Board four times over the last 10 days for comments on the RTI response and the kind of actions, if any, being taken to ensure that water consumption norms are being met. This story will be updated if and when their responses are received.
This article first appeared on IndiaSpend, a data-driven and public-interest journalism non-profit.
