Performance of a Solar Assisted Heat Pump for Building Heating: Control Problems and Improvements

Abstract

Palacus project is a solar assisted heat pump pilot plant in Genoa, Italy. The heat pump combined with solar hybrid photovoltaic thermal panels provides both electrical energy from the solar irradiation and hot water sent into the heat pump circuit. The photovoltaic field covers the energy need of the heat pump and it is even capable of producing extra electrical energy, stored in the national grid through a net-metering, looking for an energetically independent installation. The benefits coming from the net-metering, considered during the design stage, reduced dramatically due to a change in Italian laws concerning feed-in-premium. A brief report on the global facility performance during the past two years is proposed, proving the difficulties of the plant to reach its maximum design potential due to its complexity and problems related to the end users' "acceptance". Possible strategies to restore or increase the economic balance of the facility are discussed according to the new feed-in-premium criteria. Supervision and detection of any failure of the plant are performed by means of a large data acquisition system. New related regulation criteria, presented in this work, are compulsory to optimise the plant.