Explanation:

Indian Thermal power plants are one of the highest consumers of water as compared to their global counterparts. On an average, for every 1000 Kwh power, Indian Thermal power plants consume as much as 80 cubic meters of water. The water consumption in the modern Thermal power plants in developed countries is less than 10 cubic meters for every 1000 Kwh. The major reason for this atrocious figure is the widespread prevalence of 'once-through cooling systems'.
Cooling systems that use a water's cooling capacity a single time are called once-through cooling systems. These systems use large volumes of water and typically discharge the once-through water directly to waste. Large volumes of water are necessary for even the smallest once-through systems; therefore, a plentiful water supply at a suitably low temperature is needed.
The need of the hour is to gradually move towards other more efficient cooling systems like Recirculated Cooling Systems or Dry Cooling systems.