Paper No 310 – Performance analysis of a vapor-extraction heat-pump system for district heating/cooling applications – 13th IEA Heat Pump Conference, Jeju, Korea
This paper describes a new concept of a high temperature (HT)/low-temperature (LT) network integration by using an advanced heat pump technology able to integrate and manage various renewable and residual energy sources with different temperature levels. It is based on a vapor extraction (VE) compression cycle, which integrates two well-known cycles: a vapor compression heat pump cycle and an organic Rankine cycle (ORC). To perform a comparison with existing heat pumps, an energy/exergy analysis has been carried out by using R134a as a working fluid. Thus, for a given extraction ratio of 25%, results show that an increased heating/cooling capacity of about 30% and a high exergy efficiency of 59.7% can be achieved, compared to the 55.5% obtained for conventional compression heat pumps. A global coefficient of performance (COP) between 2.5 and 3.5 (corresponding to a vapor extraction ratio between 10% and 30%) is also obtained and compared to the 1.3-1.7 values given in the literature for existing thermally driven heat pumps (e.g. absorption heat pumps or double orc-orc heat-pump cycles) working with high temperature levels of hot sources.