Exergy And Energy Analysis Of Waste Heat Recovery Options For Cooling Capacity Production

Electricity production in Lebanon stands at around 1.5 GW while the demand exceeds 2.5 GW at peak times and peak cooling demands, resulting in rationing cuts from between 3 to 20 hours a day which is the worst performance in the Middle East. Due to the country energy shortfall, a large number of small-scale backup generators is installed to address the electric and cooling needs. The proliferation of use of these backup generators presents an interesting potential for waste heat recovery in order to achieve additional power generation and cooling capacity production. This paper investigates two possible configurations for waste heat recovery: A first configuration studies the potential of combining an Organic Rankine Cycle (ORC) with a conventional vapor compression refrigeration cycle (VCRC) to meet the required cooling load. A second option evaluates the possibility of using a liquid desiccant cooling system (LDCS) to handle the latent part of the cooling load, in tandem with a conventional vapor compression refrigeration cycle handling the sensible part. The investigations are based on exergy and energy analysis carried out for both configurations to assess and compare their performance.