Measurement Results and Operating Experience of Large-Scale Solar Air Conditioning Plants
Abstract
The demand for air-conditioning has increased in the past years and is expected to rise even further. As an alternative to conventional air-conditioning systems, solar cooling may be used to reduce electricity peak loads and at the same time delivering environmentally-friendly cooling. This paper aims to analyze the monitoring data of four of the currently largest solar air-conditioning systems in order to show the potential of solar cooling systems and outline trends. This is done by calculating key performance indicators considering the boundary conditions, financials as well as solar and chiller performance of each system. All solar systems performed as planned during the 7-month long calculation period, yielding more than 5.1 GWh total solar energy yield, with an average solar conversion factor of 34.6% and electric efficiency ratios of up to 26. The results also show increased performance of the solar collectors of the recently build (2017) solar system compared to the older ones commissioned in 2011 and 2014, with up to 46% higher solar conversion factors. Additionally, specific system costs decreased by approximately 70%. Even though the paper only could analyze four different solar systems with different boundary conditions, the sheer magnitude of performance and construction-cost improvements clearly supports the hypothesis that both costs and performance improved.