Waste heat is generated from the exhausts of fume incinerators, combustion engines, glass melting furnaces, and cooling water from furnaces and convective, conductive, and radiation heat losses from combustion engines and cement kilns. Waste heat is also generated from process off-gases. Heat losses in several industrial processes can be curtailed by using waste heat recovery systems. Such systems involve the capturing and reuse of waste heat for combustion air preheating, steam generation, load preheating, power generation, space heating, and waster preheating. 
These end-use industries use waste recovery methods, such as waste heat wellsprings and waste recovery hardware, such as turbines, mechanical warming boilers, and heat recovery system generators (HRSGs), to meet their energy requirements. Waste heat wellsprings encompass the exchange of heat from hot gear outside and the release of hot burning gases to the environment. Waste heat can also be recovered by using mechanical heat recovery systems that include the capture and reuse of waste heat. Deployment of such systems helps in reducing operational expenses, energy consumption, and nursery gas and carbon dioxide (CO2) outflows in manufacturing facilities.  
Waste heat recovery systems offered by Ormat Technologies, General Electric Company, Harbin Electric International Company Ltd., China Energy Recovery, Siemens AG, Amec Foster Wheeler PLC, Dongfang Electric Corporation, ABB Group, and Mitsubishi Hitachi Power Systems are used in pre-heating and steam and power generation applications in several end-use industries. In recent years, the soaring demand for the efficient use of available energy in order to facilitate climate protection and sustainable development, has resulted in the large-scale deployment of waste heat recovery systems in various industries.
Geographically, Europe emerged as the largest user of waste heat recovery systems in the recent past, due to the rising implementation of environmental policies aimed at curbing industrial harmful emissions in the continent. Whereas, Asia-Pacific (APAC) is expected to adopt waste heat recovery systems at the highest rate in the coming years, owing to the growth of the cement industry in the region. Moreover, the booming energy demand and toughening environmental protection regulations will also boost the usage of such systems in the region in the foreseeable future.  
Furthermore, North America is expected to hold the second position in the waste heat recovery market in the forthcoming years. This can be primarily ascribed to the mounting focus of the manufacturing sector on fuel efficiency and surging investments being made by manufacturers on technological improvements and optimum economic returns in the region. Additionally, the increasing compliance for environment stability and escalating focus of governments on the development of renewable and sustainable alternative energy sources will propel the deployment of waste heat recovery systems in the region in the coming years. 
Therefore, the rising electricity demand from the manufacturing sector and surging need for alternative and clean energy sources will encourage the adoption of waste heat recovery units in the foreseeable future.