ASME ORC2013

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10:20
20 mins

EXPERIMENTAL ACTIVITY ON THE COMPONENTS OF A DOMESTIC SCALE ORC COGENERATOR
Stefano Clemente, Diego Micheli, Mauro Reini, Robert Radu, Roberto Bracco, Giuseppe Toniato

Session: Prototypes I
Session starts: Monday 07 October, 10:00
Presentation starts: 10:20
Room: Van Weelde Zaal

Stefano Clemente (University of Trieste)
Diego Micheli (University of Trieste)
Mauro Reini (University of Trieste)
Robert Radu (University of Trieste)
Roberto Bracco (Centro Ricerche FIAT)
Giuseppe Toniato (Business Consultant for Riello Group)

Abstract:
The Italian research program PIACE – Small Integrated and Adaptive Platform of High-Efficiency Micro-Cogeneration Units for Residential Use – is aimed to the development of several types of micro-CHP systems for domestic application. The authors are currently involved in the experimental tests of an ORC-based prototype, characterized by the following main features: very small scale (electric power up to 5 kWe), very low cost (using components derived from HVAC field), use of eco-friendly working fluids, capability to exploit low temperature heat sources such as flat solar collectors. Two different experimental activities have been completed up to now. The first one is the study of the behaviour of a gear pump operating on R245fa, the fluid chosen for the cogenerator [1]. The pump revealed good performances, despite the very low viscosity of the fluid, but some expedients had to be adopted in order to limit the leakage of R245fa towards ambient. The second activity has been the development, the construction and the conduction of the first field tests of an complete experimental prototype of an ORC micro-CHP unit [2]. The measurements revealed promising performances for the system, even if at the moment the latter has not been optimized yet: with a maximum cycle temperature of 130 °C and a minimum temperature of 40 °C, the recorded electric efficiency has been around 0.08, while values up to 0.12 are expected after the optimization. However, some operating limits have been detected on the current version of the prototype, mainly related to an unsuitable control of the vapour quality at the boiler outlet in some working conditions: the modifications needed to improve the system are then described in the conclusions of the work.