Fraunhofer ISE has developed a propane heat pump with a refrigeration circuit requiring just 225g of charge.
Fraunhofer Institute for Solar Energy Systems (ISE) front view. Photo credit: Fraunhofer ISE.

Fraunhofer ISE Develops Propane Heat Pump for Industrial Application With a Charge of 225g

The heat pump provides heating and cooling for an industrial component cleaning machine with a combined COP of 5.6.

The Fraunhofer Institute for Solar Energy Systems (ISE) has developed a propane (R290) heat pump for an industrial component cleaning machine that requires just 255g of charge.

The machine requires both heating and cooling for its cleaning and drying processes, both of which were previously handled by electric heating and cooling components. According to ISE, the R290 heat pump achieved a combined heating and cooling COP of 5.6 relative to the electric-powered equipment previously in use. Given the size of the refrigeration circuit, ISE noted that the cleaning system would be compact enough to fit inside a room measuring just 16m2 (172.2ft2).

“As the cleaning and drying processes of the machine are carried out at both low and high temperatures, it is an ideal application for a heat pump,” said Clemens Dankwerth, Project Manager at ISE.

The power required to heat the process water for cleaning and rinsing the machine and the air for drying it were halved, and the energy needed for the heating fresh water was reduced by as much as 80%. Additionally, the condensation unit recycles the process exhaust air, recooling it in the process, which saves more than 10,000L (2,641.7gal) of fresh water annually.

ISE calculated that integrating the heat pump into the industrial component cleaning machine will bring an annual cost savings of €4,800 ($5,160) and reduction in CO2 emissions of approximately 12,600kg (27,748lbs). The figures were calculated for a facility operating two shifts per day, five days a week for 48 weeks a year.

“The use of heat pumps can make a significant contribution to the decarbonization of industrial processes,” said Dankwerth. The technology is also applicable to other processes that operate within the 50 to 70°C (122 to 158°F) temperature range, such as large dishwashers in canteens.

Previous R290 research

The refrigerant circuit for the industrial cleaning machine’s R290 heat pump came out of Fraunhofer ISE’s LC150 project, which set a goal of developing a residential heat pump that used 150g or less of propane. In November 2022, the research team announced they had created a heat pump with a heating capacity of 12.8kW (3.6TR) requiring a propane charge of 124g.

Fraunhofer ISE subsequently launched the LCR290 project to research and develop indoor-use propane heat pumps for multi-family buildings to replace gas and oil-based heating equipment.

ISE developed the R290 heat pump in collaboration with the Bavarian Center for Applied Energy Research (ZAE Bayern) and MAFAC E. Schwarz as part of the ETA in Existing Facilities project. The project seeks to increase energy efficiency in the German industrial sector. It was launched in November 2020 and is funded by the Federal Ministry for Economic Affairs and Climate Protection (BMWK).

“The use of heat pumps can make a significant contribution to the decarbonization of industrial processes.”

Clemens Dankwerth, Project Manager at ISE

Recent News

Newsletter

Go to top