Tests of an Absorption Cooling Machine at the Gijón Solar Cooling Laboratory

Final energy consumption in the residential sector is increasing, even in countries with favourable climate conditions and technological capacity to promote the use of renewable resources and energy efficiency. Air conditioning systems based on absorption cycles are common solutions in solar assisted installations. In this paper, the main characteristics of the Gijón Solar Cooling Laboratory (GSCL) are summarized, showing its ability to test cooling machines with a variety of heat sources and sinks, as well as different technologies and strategies. An absorption machine with internal energy storage in LiCl salts has been tested at the GSCL, measuring power and temperatures as a function of time during several charging and discharging cycles. During the charging cycles, the operation of the machine was analysed for various hot temperatures and power values. In the discharging cycles, special attention was paid to the refrigeration capacity produced for various chilled water temperatures. The results led to coefficient of performance COP values that are in line with those expected for this technology. Satisfactory operation of the system seems difficult at activation temperatures below 75 °C. For low levels of insolation, this limitation could lead to an increase in auxiliary energy consumption.