A review on integration of renewable energy processes in vapor absorption chiller for sustainable cooling

The building industry consumes a substantial amount of energy, particularly for heating and cooling, and so contributes significantly to greenhouse gas (GHG) emissions. The vapor absorption chiller (VAC) is one of the most often used cold generating systems for medium and large-scale cooling supplies.

Buildings have tended to more commonly use VACs to meet their cooling comfort demands in recent years due to their cost-effectiveness and flexibility of the driving source. Because of the worldwide desire to reduce emissions, the potential of VAC systems with renewable thermal energy systems has made it more appealing.

The goal of this analysis is to emphasize the potential integration of VAC with renewable energy technologies including geothermal, biomass, waste heat, surface water, and solar (thermal and PV). This study focuses on the existing and future state of VAC cooling technologies, their technical, economic, and environmental aspects, as well as the framework’s analysis and optimization techniques.

The paper places a particular emphasis on the cooling-dominated areas of India and Europe. The study finds that, local heat energy availability fosters small-scale circular economies in hot and humid climates, while the high capital costs of transmitting thermal energies across long distances, as well as transmission losses, deter centralized activities.

Since there are no HCF emissions, VACs have a major advantage over compression chillers. The findings show that combining VAC with at least four of the six renewable energy sources investigated has enormous potential for the future of clean and sustainable cooling energy alternatives. Small and medium-scale renewable cooling systems, particularly those powered by solar thermal energy, as well as bio-energy, can be cost-effective and installed in a wide range of sites.

Solar thermal energy can meet both urban and rural needs, whereas bioenergy is more suited to rural needs. Waste heat recovery systems are mostly utilized to meet industrial cooling needs, and geothermal energy offers a wide range of possible applications but is limited by availability. Bioenergy-based VAC, in particular, has the special advantage of being a carbonnegative solution if the generated bio-char is collected and sequestered.