Solar Direct Drive Refrigeration

Solar Direct Drive Refrigeration

A powerful tool for safety and equity in vaccination distribution

Description

Through End Polio Now, Rotarians have worked passionately to ensure that children in the most remote corners of the world get vaccinated. To help Rotarians respond to the worldwide COVID-19 pandemic, Steve McCarney of Sunny Day LLC and Johnny Weiss of Solar Energy International (SEI) gave a talk to ESRAG’s Renewable Energy Task Force in February, 2021, on the use of solar direct drive (SDD) refrigeration to store vaccines at safe temperatures in communities without reliable electric power. These systems can now generate some additional electricity for other basic needs.

As a consultant to the World Health Organization (WHO), McCarney developed specs for battery-free solar-powered refrigeration kits, with built-in cold storage for backup to ensure they can maintain proper temperature through the night and for several days if the sun is not shining. A hundred models of fridges and freezers meet the specs and have been pre-certified for purchase by UNICEF. These systems maintain temperatures of +2 to +8 degrees Celsius, consistent with safe storage of the Oxford AstraZenica COVID vaccine. A list of the WHO prequalified appliances.

The battery-free technology came out of NASA research in the 1990s. It liberates local communities from the logistics and costs of replacing batteries or relying on fossil-fuel powered generators. McCarney and Weiss also described the opportunities for clinics to tap excess electricity generated by these same solar fridge kits to power other equipment health centers need, such as lighting, communications, and even select small medical devices like the fetal Dopplers and otoscopes. The systems are rigorously designed to ensure that the refrigerator or freezer always has the power it needs to maintain proper temperatures for storing vaccines and medications. Rotarians who are supporting health centers will find this article by PATH exciting: https://www.path.org/articles/solar-power-people/

Vaccine storage in areas without reliable power is an essential part of cold-chain logistics for vaccination campaigns. Visit this link for UNICEF’s 2018 guide to solar direct drive refrigeration systems.