According to the report from the National Commission for Integrated Water Resource Development, in a high-use scenario, the water requirement is likely to be 1180 BCM by 2050, while the current surface water availability is 695 BCM.
By Gurdeep Singh
The post-pandemic era, rising population, rapid economic growth and climate change pose enormous challenges in terms of water availability worldwide. We are at a critical point where the food, energy and water crises call for a shift to sustainable development practices. In January 2022, the World Economic Forum (WEF) released its latest Global Risk Report, which lists the natural water crisis as one of the top 10 risks to humanity. At present, about 36% of the world’s population (2.8 billion people) lives in areas of high water scarcity; this could rise to more than 50% by 2050.
The looming crisis has turned water into another commodity like gold and oil, leaving fundamental human rights in the hands of financial institutions and investors. As water scarcity increases, the rivalry between sectors and regions will only increase. This makes companies very vulnerable during a crisis, especially as they are the last priority in water allocation. This puts more pressure on them to optimize water use.
In our country, industry is the second largest consumer of water after agriculture. According to the report from the National Commission for Integrated Water Resource Development, in a high-use scenario, the water requirement is likely to be 1180 BCM by 2050, while the current surface water availability is 695 BCM. The UNEP Finance Initiative highlighted the dynamics of water-related security impacting companies’ ability to service debt, creditworthiness and reputation, the core for achieving ESG ratings. The drivers of water efficiency in various industrial sectors have attracted the attention of experts. I will focus on avenues for judicious water management in the energy sector, as water is critical to power generation.
Public policy perspectives on water efficiency have changed significantly since nationally determined contributions and recent net-zero considerations have dominated public debate for the past 4-5 years. It is essential to examine water use throughout the value chain. The center gave impetus to improve water use efficiency by limiting it for thermal power plants. The sector, in turn, examined dry cooling using technical and economic parameters to determine the expected reduction in water consumption. About four years ago, the Ministry of Energy also emphasized increasing energy efficiency in the energy sector. This was also when efforts to integrate renewable energy with thermal energy gained momentum. Accordingly, the NTPC became a signatory to the UN Global Compact CEO Water Mandate. Inspired by the elements of governance, NTPC is evolving as a water manager, evident in our innovative seven-pronged approach adapted to installations with a long commercial life.Mutual reinforcement of a wastewater recycling system: This includes the recirculation of ash water and the recirculation of the toe discharge in ash processing systems. As a preventive strategy, dry bottom ash processing systems also help reduce water consumption. Increasing Concentration Cycles in Cooling Water Systems: A typical closed cycle 660 MW (supercritical technology) coal-fired power plant operating at 85% PLF consumes approximately 16 MCM of water annually with ash water recirculation system. Most is used for cooling (70%), followed by ash processing with flue gas desulphurisation systems (8%) and demineralization (3%). These ratios vary depending on technology features, fuel type, cooling systems and operating efficiency/load. The plant can save an additional 16% water by reducing the blowdown rate just by increasing the concentration cycles in circulating cooling water systems. Ensure no liquid runoff: Rainwater runoff and plant water drains are separated to ensure significant water savings.Rainwater collectionA graded system to collect wastewater within factories reuse and recycle. Implementation of dry cooling systems: This is a viable option to reduce water consumption. Air-cooled condensers are integrated into NTPC’s operations in two power plants currently under construction and are designed to reduce water consumption by approximately 75%. Use of alternative water to meet all freshwater requirements: Ratnagiri Gas and Power Private Limited (RGPPL) of NTPC, Maharashtra met 139% of its freshwater needs internally in 2020-21 through strategic actions for rainwater harvesting and water reuse in factory processes and supplies excess freshwater to nearby villages.
A greater share of renewables in India’s energy mix will ease the pressure on water availability in the long term. This includes opportunities to use renewable energy to extract, supply, reuse and treat water, and to implement integrated corporate-level regulation and market responses to reduce water-related risks from mismanagement. For the most part, thermal power generation and freshwater abstraction will either be moved to watersheds that face less water stress, or will adopt cooling technologies with low water consumption. Scaling up the above technologies and process innovations to all thermal stations in the country will bring benefits in the short and medium term. It is critical to come up with nature-based solutions to improve adaptation outcomes to ensure water is used wisely. Such interventions will strengthen India’s Jal Jeevan mission and ensure that clean drinking water from the tap reaches all corners of our country.
The author is chairman and director of NTPC Limited.
This post Enabling water savings: In thermal energy generation, technological and process innovation must be integrated to ensure judicious use of water was original published at “https://www.financialexpress.com/opinion/powering-water-conservation-thermal-power-generation-will-need-to-integrate-tech-process-innovation-to-ensure-judicious-use-of-water/2467182/”