The project aims to:

Extend/expand medical and public health programs relying on refrigeration

Reduce wastage of vaccines, blood products, and medicines

Build manufacturing and design experience for mobile refrigerators

Integrate manufacturing, deployment and maintenance for these alternative refrigerators developing the supply chain. and

Apply mobile refrigeration to other development program challenges

Refrigerators based on solar-assisted evaporative cooling can store high-value vaccines, blood-borne products, and drugs making high performance refrigeration technically feasible for extreme and remote locations. The need for this technology is undeniable: A study by the US CDC estimated that in 2002 more than 1.1 million children died in Africa due to vaccine-preventable illnesses, (http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5518a4.htm)

 Unlike today's commercial refrigerators that are focused on manufacturing design efficiencies, mobile refrigeration technology focuses on energy use efficiency to enable temperature controlled environments in any geographic region. This is done by harnessing transported heat energy through the desorption of heat transfer fluids immersed in the solar environment.

A team from the U of Mich will design, build, and evaluate the performance of prototypes for mobile solar refrigerators. Our proposed goal is to partner with development programs that deliver medical treatment and care to those who would benefit most from this game changing innovation. Our initial geographic deployment focus targets sub-Saharan Africa, due to the combination of high solar flux and pervasive development program partners.

How does it work? Current commercial refrigerators make use of compressors which require large power loads to create an evaporative cooling cycle. Traditional solar-powered refrigerators require large solar cells and inverters to drive the mechanical compressor. In contrast, solar evaporative cooling systems use the sun to passively heat and desorb convection fluids that evaporate and expand through a check valve, creating the cooling process. The idea is to cool in the daytime and recharge during the night. The amount of heat transfer fluid available to vaporize regulates the cooling capacity. The cooling system will be optimized to make vaccine storage possible indefinitely.