Performance analysis of a novel control system for solar collectors coupled with sorption chillers

This paper presents work on a holistic approach for improving the overall design of solar cooling systems. Newly developed methods for hydraulics and control were used to redesign an existing pilot plant. Measurements taken from the newly developed system show that target temperature control leads to an 81% increase of the Solar Cooling Efficiency (SCE) factor compared to the original pilot system. In addition to the improvements in system design, new efficiency factors for benchmarking solar cooling systems are presented. The Solar Supply Efficiency (SSE) factor provides a means of quantifying the quality of solar thermal charging systems relative to the usable heat to drive the sorption process. The product of the SSE with the already established COP of the chiller, leads to the SCE factor which, for the first time, provides a clear and concise benchmarking method for the overall design of solar cooling systems.

► We present the details of a redesigned solar-driven sorption cooling system.
► The new system employs more holistic design with more sophisticated hydraulics and control strategies.
► The new control strategies are based on target temperature control rather than traditional, temperature difference control.
► Performance data collected from the new system show an 81% improvement in the solar cooling efficiency and a 53% increase in the cooling output.
► We present new performance factors for use in benchmarking solar cooling systems.