ShareSolar-powered off-grid cooling: An innovative prototype for remote areas
An innovative solar-powered refrigerator could transform the preservation of perishable goods in areas without electricity.
An article published in the January 2025 issue of the International Journal of Refrigeration [1] presents an innovative solar-powered refrigerator designed to preserve perishable products without relying on the electrical grid.
The system is based on a 160W solar panel and an MPPT (Maximum Power Point Tracking), a technology that ensures the solar panel operates at its highest efficiency by constantly adjusting its operating point to match changing environmental conditions for optimal energy production. The energy generated is stored in a lead-acid battery, which powers a refrigerator using the natural refrigerant R290, known for its low environmental impact. The key innovation lies in the use of phase change materials (PCMs), specifically water, to maintain stable temperatures and extend the system’s autonomy without external power.
Outdoor tests have demonstrated that the refrigerator could maintain a target temperature between –1°C and +1°C for extended periods, even during door openings, which is a challenge for conventional refrigerators. The integration of PCM allows the refrigerator to store thermal energy during the melting phase and release it during solidification, thus ensuring thermal regulation without the need to activate the compressor.
The advantage of this system lies in its complete energy independence, made possible by the combination of solar technology and PCMs. This type of refrigerator is particularly suited for areas with unreliable electricity access or in contexts where the preservation of perishable goods is critical, such as in the medical (vaccines, medications) or food sectors. Additionally, by using R290 as the refrigerant, this refrigerator offers a more environmentally friendly solution compared to traditional units that use greenhouse gases.
This prototype could meet the growing demand for sustainable, autonomous refrigeration, especially for products requiring strict temperature conditions in isolated areas or regions with low electrification. In addition to its benefits for vaccine preservation, the system can be adapted for food storage and other temperature-sensitive substances. Tests conducted on products like water, as well as saline solutions, have shown the system’s effectiveness under various climatic conditions, providing a reliable solution for the most demanding environments.
Source
[1] Maiorino, A., Petruzziello, F., Grilletto, A., Cilenti, C., & Aprea, C. (2025). Achieving off-grid refrigeration in remote areas: A solar-powered vapor compression refrigerator prototype with PCM integration. International Journal of Refrigeration, 169, January 2025. [Download in FRIDOC - Free for IIR members]
Did you know?
On the same topic, the IIR has published a practical guide titled Walk-in cold rooms, a practitioner’s technical guide – Design and operation of walk-in cold rooms for precooling and storage of fresh produce in hot climates, in off-grid and unreliable grid situations. This guide provides technical solutions for designing and operating cold rooms suitable for areas with unreliable or no electricity grid, offering a sustainable approach to fresh produce storage in hot climates. [Download for free in FRIDOC]
More about IJR
The International Journal of Refrigeration is published by Elsevier on behalf of the International Institute of Refrigeration The journal is a must-read for keeping abreast of the latest research and industry news in refrigeration, air conditioning, and related fields. With a focus on emerging technologies and alternative refrigerants, it covers key topics such as heat pumps, food refrigeration, CO₂, ammonia, hydrocarbons, magnetic refrigeration, sorptive cooling, and solar cooling, along with advances in compressors and ejector technology. [More information]