PDF Publication Title:
Text from PDF Page: 024
Technological innovations in heat pump systems 285 Figure 27. Heat exchange system for surface water (a lake) and heat pumps. the temperature levels during the year and of the temperature values. In the case of surface water utilisation it is not always necessary to directly pump the water: surface water heat exchangers can be used in the form of long and cheap HDPE coils as represented in Fig. 27. Finally ground coupled heat pump systems must be considered. The cold source is more and more often obtained by vertical tube heat exchangers that sometimes exceed 200 m depth. This subject is outside the purpose of this paper. It is important only to recall the thermal stability of the ground at higher depths and the possibility of using the system as a kind of a seasonal storage. For a size of 50 W/m of tube for the probes, a SPF (Seasonal Performance Factor) of 4.5 can be reached. This value can be improved by reducing the temperature drops from the ground to the heat pump. A lot of systems use a secondary fluid to take heat from the ground to the heat pump. Few systems (widespread in Austria) use direct expansion [11]. Recently a very innovative proposal provides vertical heat pipes, where the fluid is carbon dioxide (Fig. 28). This would eliminate the energy cost of the brine circula- tion and the hazard of the fluid leakage in the direct expansion systems. A hundred plants have been built up till now with a heat pipe that sometimes exceeds 65 m with a temperature drop between the two pipe sides of only 2oC. A pipe as deep as 100 m is being experimented. This diversified picture of the state of the art heat pipe equipment and systems terminates describing a really innovative plant built up in Holland. The plant was set into operation in 2003: nine blocks with 382 40-year-old apartments were retrofitted for higher energy efficiency. The first action was better insulation regarding both the walls and the windows. Secondly a mechanical ventila- tion system with heat recovery was installed in each apartment. Thus heating demand International Journal of Low Carbon Technologies 2/3 Downloaded from https://academic.oup.com/ijlct/article/2/3/262/758006 by guest on 21 June 2022PDF Image | Technological innovations in heat pump systems
PDF Search Title:
Technological innovations in heat pump systemsOriginal File Name Searched:
2-3-262.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |