Propane refrigerant heat pump developed in Spain

A project team from the Polytechnic University of Valencia says it has developed a heat pump that produces zero direct and indirect emissions. 

The new-type heat pump uses propane, a natural refrigerant, that allows for high energy efficiency while producing almost zero carbon dioxide emissions, according to the researchers. They say its high efficiency earns it an A+++ rating, with the unit capable of producing 6.48kW/h for each kilowatt it consumes. 

In addition, data shows the Spanish heat pump can generate 4.43kW/h domestic hot water, up to 75ºC, which most conventional models cannot do. This allows for anti-legionella cycles without the need for external support.

José Gonzálvez, director of the Thermal Department of the Research Institute for Energy Engineering at the university, explains that the propane-based heat pump can be installed in both new and existing buildings, making it suitable for replacing gas boilers. 

“It is the first commercial domestic equipment with zero direct and indirect emissions. Right now, there is already equipment that uses the same technology as ours, which is aerothermics, but does not use a natural fluid such as propane inside it,” says José Gonzálvez.

“We have managed to achieve energy efficiencies similar to the currently used refrigerants with high atmospheric heating power. To do this, we carried out an analysis of the best configuration of the vapour compression cycle adapted to the refrigerant used – propane – minimising the amount used and optimising the control parameters of the equipment.

“And in the coming years, the main challenge will be to increase the efficiency of these appliances at low ambient temperatures and to equip them with an intelligent system that allows early detection of faults or degradation of their efficiency over time,” concludes José Gonzálvez.

The project team comprised researchers from the Polytechnic University of Valencia in Spain and heating specialist Saunier Duval, a division of Vaillant Group in Germany.