New piston engine produces electricity from waste heat

A new piston engine, developed by Empa experts and partners, uses industrial waste heat more efficiently and could come onto the market thanks to an "Empa Entrepreneur Fellowship" from researcher Andyn Omanovic. The machine is based on an innovative valve control system that makes gas exchange more flexible and reduces fuel consumption. This technology is already used in fuel-flexible engines in commercial vehicles, for example. However, it could now also be used to generate electricity wherever waste heat from industrial processes is generated in large quantities. The waste heat is converted into mechanical power via the pistons, which is then used to generate electricity. However, this process can only be implemented at all thanks to a new type of flexible valve control.

The new reciprocating engine is particularly suitable for temperature ranges from 500 to 900 degrees and power ranges up to several megawatts. Potential applications include the use of waste heat from pyrolysis plants for biochar and the combustion of lean gases. A pilot machine for the energy supplier IWB in Basel is planned by the beginning of 2025, followed by a small series for a company specializing in gas combustion plants. Technical challenges such as temperature-resistant materials and control strategies still need to be overcome, but the cost-benefit calculations are promising, according to a press release from Empa. However, more temperature-resistant materials still need to be found for the machine, and the control strategy for the thermodynamic process also requires further adjustments.

Source and further information: Empa