heat pumps

A group of researchers in Thailand outlined a new methodology to identify the optimal temperature in two-stage cascade heat pumps using non-azeotropic refrigerants. Through their analysis, the scientists found that the coefficient of performance for simultaneous heating and cooling is affected by the pinch point temperature at the cascade heat exchanger, with lower temperature levels being responsible for a higher COP.

An international research team has investigated how thermoelectric subcooling may be integrated into propane heat pumps to reduce power consumption in the vapor compression system. Their work showed this combination can not only reduce electricity consumption but also significantly improve heat pump performance.

Researchers in the United Kingdom have presented a new heat pump system that may avoid reducing heat supply during defrosting operations. The proposed concept can reportedly execute defrosting operations while ensuring continuous heating by condensing the refrigerant in the frosted evaporator.

Developed by a Chinese research group, the novel refrigerant is made of a mixture of carbon dioxide (CO2) and a non-flammable hydrofluoroolefin. It has slightly higher costs compared to conventional compounds, but its creators claims these costs could be significantly reduced with large-scale industrial production.

The largest heat pump in the Netherlands is now online at the Utrecht sewage treatment plant. It generates heat up to 75 C for the local network by using purified hot wastewater from a regional water authority.

UK scientists designed a new heat pump concept that they claim could be particularly beneficial to newly developed areas or potential residential complexes. The system uses ice or ice slurry as the heat source and its energy consumption is reportedly lower than that of several types commercially available heat pumps.

The Chinese manufacturer said its new propane heat pump doesn’t need an outdoor unit and is able to operate with temperatures down to -20 C.

The Japanese manufacturer said the new Climaveneta EW-HT-G05 products have a size ranging from 73 kW to 129.3 kW and a coefficent of performance of up to 3.77.

Helen, a Helsinki-based energy company, has unveiled plans for a large-scale district heating plant complex. Germany’s MAN Energy Solutions is supplying a 33 MW air-to-water heat pump, the largest ever used for a district-heating plant, with ambient air and renewable electricity for heat generation.

The UK-based manufacturer said the new Ecomod products have a size ranging from 14 kW to 70 kW and a coefficent of performance of up to 4.85.