While the African Union has secured 270 million vaccine doses for distribution across the continent, in addition to those promised by the global vaccine program COVAX, this could still fall short of demand for the region. Even if enough vaccines are secured, there is an enormous logistical challenge: how to transport temperature-sensitive vaccines to places without reliable electricity and refrigeration. The answer is in developing a “cold chain” — a network of vehicles, fridges and cold rooms — that can be used to transport the vaccine seamlessly from the manufacturer to the immunization point. This is where solar energy comes in, says Hugh Whalan, CEO of PEG Africa, a company that offers pay-as-you-go solar-powered products to people in West Africa. In preparation for a Covid-19 vaccination drive, the company — with funding from Power Africa, a network of private and public groups set up by USAid — has started providing solar-power systems to off-grid health clinics. Previously, PEG Africa’s refrigeration efforts had focused on establishing a cold chain for food products, helping produce get to market without spoiling. It is currently testing pay-as-you-go solar freezers among fisherwomen in Ghana, Ivory Coast and Senegal. Gricd, a small Nigerian startup, is hoping to help fill this gap. It’s building solar-powered cold boxes for vaccine transportation that can be kept at minus 20 degrees Celsius (minus 4 degrees Fahrenheit) and can be controlled remotely and monitored in real time. They also contain a device that monitors location, humidity and temperature, and transmits this data to the distributor in real time.