Green electricity from low-temperature heat

The manufacturing sector is vitally important to the EU economy. With small and medium-sized enterprises (SMEs) representing 99 % of the sector, manufacturing contributes around 17 % of EU gross domestic product and accounts for 22 million jobs. Being resource intensive both in terms of raw materials and energy consumption, SMEs are under increasing pressure to remain competitive against non-EU-based companies.

Funded by the EU, the project ICARUS (An innovative, environmentally friendly CO2/lubricant absorption power system for highly efficient power generation from low temperature industrial waste heat to reduce emissions and costs) successfully developed a 5-kW prototype system that provides cost-effective heat recovery, reducing electricity demand and carbon dioxide (CO2) emissions.

After exploring end-user requirements for the system, scientists developed thermodynamic models to evaluate the most suitable working fluid in terms of system efficiency and operating pressure. In addition, they identified a suitable expander that generates the electricity as the working fluid passes through it.

The heat from the waste heat stream is transferred to an absorption system. An absorption power generation system achieving the cost and power requirements for low-temperature heat recovery would be a real breakthrough in the industries. The developed system enables electricity to be generated from industrial waste heat without affecting industrial processes, with conversion efficiency up to 20 %.

Project work laid the groundwork for follow-up projects to design innovative technology such as a 20-kW organic Rankine cycle system for commercial use. This unit should reduce CO2 emissions by approximately 90 tonnes in the United Kingdom and 120 tonnes in Greece.