Gas heat pumps, the ready-to-use model for housing thanks to the European project

A multidisciplinary team of 25 professionals that for years has worked full-time on the project. A global investment of around EUR 10 M. Fourteen partners, among others ENEA, Technical University of Milan, English British Gas, and German Bosch and E.ON. These are the figures regarding “Heat4U,” the project coordinated by Robur that was included in the Seventh Framework Programme of Research and Development of the European Community. Its goal was to extend the scope of application of methane-absorption heat pumps, already used in the light commercial and industry sector, which put this technology at the disposal of the existing residential buildings. On the occasion of presentation of the final project results, held at the main office of Robur in Verdellino (Bergamo) on November 13, we interviewed Luigi Tischer, coordinator of “Heat4U” and Strategic Business Director at Robur, who told us about this European experience.

Let us begin from the most technological aspects: what are the operational principles of these machines?

We apply the technology of absorption: in the classic refrigeration cycle, also used in the electric heat pumps, the mechanical compressor (used in the electric machines) is replaced with a thermal one. This allows avoiding both the compression energy absorption and a typical problem of electric machines related to the energy dispersion. Indeed, if in an electric heat pump major energy dispersion occurs due to an increasing pressure difference between aspiration and discharge (a phenomenon related to the difference in temperature between the evaporator and the condenser), such a problem is limited by means of a thermal compressor, as the pressure growth in the thermal machine is produced by pumping that is in an intrinsically less entropic process. Thus when the temperature difference grows, while an electric machine tends to lose efficiency in a considerable manner (the compressor loses efficiency when the pressure difference increases), in a machine where the absorption is provided by the thermal compressor, such a loss is basically negligible. 

What are the advantages in terms of reduction of consumption and emissions of polluting substances?

The tests conducted show that the consumption reduction by over 35%, which is therefore and important result obtained without the need to renovate the building. For instance, in a detached house of about 200 square meters with ordinary consumption, for 4 people, this saving means a reduction of about EUR 1000 a year for methane and about EUR 3000 which such a household would spend for a normal condensing boiler. Also in terms of CO2, PM and NOx emissions the data are extremely positive. According to a study that the DG Environment conducted in the framework of the Ecolabel programme, the absorption technology used in heat pumps is actually the one with a minor environmental impact.

 

Per ricevere quotidianamente i nostri aggiornamenti su energia e transizione ecologica, basta iscriversi alla nostra newsletter gratuita

Nome *

Email *

Accettazione Privacy *

• Iscrivendoti alla newsletter accetti la nostra privacy policy. *

Invia