Demierre, JonathanFavrat, DanielSchiffmann, Jürg AlexanderWegele, Johannes2014-07-252014-07-252014-07-25201410.1016/j.ijrefrig.2014.04.024https://infoscience.epfl.ch/handle/20.500.14299/105275WOS:000342863900011This paper presents the experimental investigation of a concept of Thermally Driven Heat Pump (TDHP), based on the coupling of a vapor compression heat pump cycle and an Organic Rankine Cycle (ORC). The studied concept uses a single stage centrifugal compressor directly coupled to a single stage radial inflow turbine. The shaft is rotating on gas bearings, which allows the system to be oil-free. Like most of the other TDHP's, this system has the advantage to work with a variety of fuels or heat sources like wood pellets, natural gas, solar heat, geothermal heat or waste heat. A prototype using R134a as working fluid and with a heating capacity of about 40 kW has been developed. The results of the first tests are presented. (C) 2014 Elsevier Ltd and IIR. All rights reserved.Thermally Driven Heat PumpOrganic Rankine CycleRefrigerant vapor bearingsOil-freeMicro-turbomachinesSupercritical evaporationtext::journal::journal article::research article