Performance comparison of solar autonomous and assisted absorption systems in Spain

Solar-powered air conditioning systems can reduce electricity consumption and peak demand. The objective of this work was to develop and validate a TRNSYS model of the solar air conditioning installation at the Universidad Miguel Hernández de Elche. The model was then used to study the operation of the facility as an autonomous system and as a solar-assisted system (with backup) under different climatic conditions in Spain (Barcelona, Madrid, Bilbao and Seville). The autonomous system was able to maintain the comfort temperature between 60.8% (Sevilla) and 78.3% (Madrid) of the hours for the studied period. Working with a backup compression chiller, the cooling provided by the absorption chiller ranged from 52.8% of the total cooling demand in Bilbao to 75.3% in Madrid. The high initial cost and the high associated electricity consumption explain why the binomial solar thermal collector-absorption machine has failed to break into the market so far.