If there were one thing within energy efficiency where a significantly higher focus has to be employed during the next five years, it would be waste heat recovery in large manufacturing and process sectors.
While a large number of solutions and solution providers have emerged to make the electricity side of industrial energy more efficient, the heat part of the energy has been a more difficult domain to tackle for deriving efficiencies. Waste heat recovery is the lowest hanging avenue in this context.
It was thus with interest and optimism that I read about the Indian cement companies' plans to invest heavily in waste heat recovery. Given that cement plants operate at very high temperatures and are massive users of energy - cement manufacturing is an energy-intensive process and power and fuel account for 25-28% of the overall cost - this is indeed an important development.
India's major cement companies invest Rs 1700 crore to set up a 175 MW Waste Heat Recovery System (WHRS) - which could translate to about Rs 1400 - 1700 crore of investments.
By generating power using the hot gases produced during the manufacturing process, WHRS also helps in augmenting the operating profitability, as the cost of power generation using WHRS technology could be less than half that for captive thermal power. With reasonable assumptions, this could lead to improving the operating margins by 1-2% - not a bad sum at all, given that the company is also significantly cutting down on carbon emissions along the way.
