Over a billion people around the globe lack access to reliable sources of electricity. This hinders economic growth, limits education and reduces the safety and wellbeing of communities around the world. Most critically, a lack of electricity often prevents access to adequate medical treatment, since clinics and hospitals that lack or lose power have difficulty running important medical devices. This is especially problematic for administering vaccines, most of which need to be kept at a constant temperature between 36 and 46 F.
Current Solution: Sunlight, Diesel and Lead
Several organizations around the world, such as US Aid’s Power Health, are working to find ways to provide electricity to health stations. Current systems rely on diesel generators, solar panels, batteries or a combination of all three in order to guarantee constant power. Solar panels are relatively common, and are used in as many as 50% of the health centers in certain regions of Africa.
As we discussed in our post on supporting off grid renewable energy, energy storage for auxiliary generation must be used to guarantee reliable power. To power a center with sustainable energy, a small PV array could support the system during the day and charge up batteries with excess energy. The batteries are then discharged at night to power the necessary devices. Lead acid batteries are most commonly used for these types of systems, but they face problems with depth of discharge and short lifetimes.
Diagram of an off-grid PV-power vaccine cooling system
The Aqueous Hybrid Ion Energy Storage Solution
AHI batteries offer a unique solution and valuable factors for medical support; they are safe and long lasting. Furthermore, they allow for a large depth of discharge, decreasing the number of batteries needed for a system.
To demonstrate this solution, we designed and built a small off-grid photovoltaic system supported by our AHI batteries. The solar panels supply power to the batteries, which were installed along with a charge controller inside a portable protective case. The system supplies power to a high-efficiency freezer located inside our shipping container workspace dubbed the “Boxcar Bungalow.” The freezer works equally well chilling vaccines as beers.
170 W photovoltaic array
Photograph of case containing AHI batteries and charge controller
High efficiency refrigerator. Uses only 45 Wh per day, considerably less than a similarly sized standard refrigerator
Results of Our Case Study
The system is built and in use, and has been operating successfully for the past several weeks. We will post updates as we continue to run and refine the system, as well as a more detailed finacial and technical analysis.
PV Panels: Qty 2 SunTech STP085B-12/BEA 85W 12V Module
Charge Controller: Morningstar SunSaver MPPT 15A
Batteries: Qty 2 Aquion Beta Battery Modules, (400 Wh nominal)
Case: Pelican hard case
Freezer: Sundanzer 1.8 CF battery powered refrigerator, 45 Wh / day
For some great resources on this topic, check out US Aid’s Powering Health website
Learn more about AHI battery applications by checking out our applications page.