Pumped solar heating system with vertical flat-plate collector

Abstract

This paper presents work conducted on a vertically-mounted solar collector in a domestic solar water heating system installed in Malta. The aim of the project was to determine characteristic performance parameters of this concept by carrying out a number of tests during three winter months in the Mediterranean island of Malta; namely during the period November 2009 to January 2010. The system consisted of a flat plate solar collector mounted vertically on the Institute for Sustainable Energy’s (ISE) rooftop. An insulated vertical hot water storage tank was installed on the ground floor inside the ISE building. Several tests were conducted on the system including ISO Standard compatible tests. The overall efficiency of the system during those months was found to be around 30%. When monitored individually, the solar collector had a maximum efficiency of 80% and this dropped in accordance with the manufacturer’s specifications. The heat exchanger in the hot water storage tank was found to have an efficiency of around 45%, which indicated that this is one component that requires improvement. On a similar note, the hot water storage tank in its current configuration only allowed for a hot water drawoff of around two-thirds of the tank’s capacity at the same temperature.