Traditional cooling systems are notorious energy consumers, but as cities grapple with rising temperatures, the shift toward Vapor Absorption Chillers (VAC) is proving to be a game-changer for large-scale sustainable cooling. Unlike standard air conditioners that rely on electricity-hungry compressors, VACs use heat to drive the cooling process—making them the perfect partner for renewable energy.
This research explores how integrating VACs with sources like solar, geothermal, and biomass can revolutionize the cooling landscapes of both Europe and India.
The study takes a deep dive into the technical and economic frameworks of these systems, comparing how they perform across different climates and scales.
By analyzing the integration of VACs with six renewable sources—geothermal, biomass, waste heat, surface water, and solar (both thermal and PV)—the researchers sought to identify the most cost-effective and low-emission pathways.
Their findings reveal that local heat availability is the primary driver of success; in hot and humid regions, small-scale bio-energy or solar thermal systems can create efficient “circular economies,” while centralized systems often struggle with the high costs and energy losses of transporting thermal energy over long distances.
One of the most exciting takeaways is the environmental edge: because VACs don’t use HCF refrigerants, they avoid the potent greenhouse gases associated with traditional compression chillers. The research highlights that bio-energy-based VACs, in particular, offer a rare carbon-negative opportunity if the bio-char produced during the process is captured and sequestered.
Ultimately, the paper concludes that while solar thermal is the most versatile solution for both urban and rural needs, the future of clean cooling lies in decentralized, renewable-driven VAC systems that turn waste heat and local resources into a comfortable, sustainable climate.
Learn more about this study here: https://doi.org/10.1016/j.seta.2021.101822
Reference
Hara Chakravarty, K., Sadi, M., Chakravarty, H., Sulaiman Alsagri, A., James Howard, T., & Arabkoohsar, A. (2022). A review on integration of renewable energy processes in vapor absorption chiller for sustainable cooling. Sustainable Energy Technologies and Assessments, 50