Toward sustainable refrigeration systems: Life cycle assessment of a bench-scale solar-thermal adsorption refrigerator

Adsorptive refrigerators are an unconventional alternative to modern refrigerators employing the vapor compression cycle. Adsorptive refrigerators do not require electricity and can be constructed from widely available and environmentally benign materials, making them a particularly appealing approach to creating refrigeration in remote, impoverished areas where electricity is unavailable or unreliable. This paper describes a prototype that uses ethanol and activated carbon, two widely available and environmentally friendly materials, as the key components of a solar-powered adsorptive refrigerator. The Solar Thermal Adsorption Refrigerator (STAR) prototype obtained temperatures between 2 degrees C and 8 degrees C on the external wall of the vacuum tube. Results showed that a significant amount of life cycle environmental benefits can be achieved from STAR compared to a conventional refrigerator. Successfully replacing a conventional refrigerator with STAR can annually reduce: 292 similar to 1170 kg CO2-eq of global warming potential (GWP); 104 similar to 418 H+ moles-eq. of acidification; 1.15 similar to 4.61 kg benzene- eq. of carcinogenic; 6850 similar to 27,400 kg toluene-eq. of non-carcinogenic; 1.2 similar to 4.78 kg N-eq. of eutrophication; 0.556 similar to 2.22 kg PM2.5-eq. of respiratory effects; 0.0078 similar to 0.031 g of CFC-11 eq. of ozone depletion; 0.564 similar to 2.26 g NOx-eq. of smog. Considering the typical lifetime of a conventional fridge of 1319 years, the reduction of the aforementioned environmental impacts of the STAR can be scaled significantly. (C) 2020 Elsevier Ltd and IIR. All rights reserved.

Automated summary

Adsorptive refrigerators are alternative cooling devices that do not require electricity and can be made from environmentally friendly materials, providing refrigeration in remote areas. The STAR prototype showed significant environmental benefits compared to conventional refrigerators, with reduced global warming potential, acidification, and other harmful emissions.