The government has drawn up a plan to tap waste heat as a source of power. In a draft policy, the ministry of new and renewable energy estimates that the potential in selected industrial sectors for waste heat power generation (WHP) is about 5,000 megawatts (MW).
According to the draft, as much as 20-50% of the energy used by industry is wasted, being released into the environment in the form of exhaust gases and liquids that flow out of plants.
“The industrial sector accounted for 44% (532 billion KWh) of total electricity consumed (1,208 billion KWh) in India for the year 2015. Even considering 30% of this energy input being wasted by industry amounts to 160 billion KWh annually, equivalent to 20,000 MW of coal-based power generation capacity. This huge amount of waste heat is caused due to equipment inefficiencies and thermodynamic limitations of the equipment/processes,” the draft said.
Industrial facilities can reduce this wastage by installing waste heat power systems to improve overall equipment and process energy efficiency, it said.
“Waste heat power generation will reduce the energy consumption per unit of production for Indian industries. Also WHP will result in savings of fossil fuels like diesel, high-grade coal, and furnace oil mainly used for captive power generation and thereby reduce the nation’s GHG (greenhouse gas) emissions,” the draft added.
The ministry has asked all stakeholders to come up with comments and suggestions by December end.
The National Democratic Alliance government has set an ambitious target of generating 175 gigawatts of renewable power by the year 2022.
The potential for waste heat power from industrial and non-industrial processes for countries such as the US is 7,000-10,000 MW of generation capacity.
India’s potential for power generation through waste heat is significant as its industries are much less energy efficient when compared with advanced countries.
Sectors that have the potential for generating the estimated 5,000 MW of waste heat power include cement, glass, iron and steel, aluminum, food, petroleum refining, chemicals, ceramics and pulp and paper.
The draft policy also states that the electricity generated from waste heat power can displace power from sources that produce emissions such as coal-based thermal power plants.
“Waste heat power reduces its consumer’s reliance on fossil fuel-based power generation. Generation of electricity from WHP does not add any carbon dioxide or heat to the atmosphere. Emission/temperature level remains almost the same even with increased generation capacity of electricity without using fossil fuels,” said the policy, enumerating the benefits of WHP.