Unreliable access to electrical power in remote areas is a barrier to maintaining potency of vaccine products. Approximately 1.6 billion people today do not have
access to electricity, and four out of five people having unavailability of electricity live in rural areas (Birol, 2002).The
most common cooling system utilized for cooling vaccines at health posts is with the vapour compression refrigerator
and cold boxes. The vapour compression system employs mechanical pumps to actuate the compression and the
subsequent expansion of specific working fluids. The advantage of this system is that it is capable of refrigerating
large loads with high efficiency. However, the system is heavy due to the compressor, is costly and noisy during
operations. Thus, the system is not suitable or readily portable to remote areas. Alternatively, the cold box (vaccine
carrier), which weighs and costs less, simply uses an ice pack to cool the vaccines. It is much less reliable, and offers
cooling over a relatively short duration. Another alternative cooling technology which is becoming increasingly
popular and attractive to the portable cooling application is thermoelectric modules. The modules are made of
semiconductor materials electrically connected in series configuration and thermally in parallel to create cold and hot
surfaces. Although they are less efficient than the vapour compression system, they are very light, low in cost, silent
in operation, and are environmentally friendly. In this project work, the thermoelectric module was utilized for cooling.
The objective of this present work is to develop a workable portable thermoelectric cooling system with a capacity of
4 liters of vaccine chamber, with the temperature maintained between +10 °C to +12°C. It will be used in remote
locations in the world where there is no grid electricity, and where electrical power supply is unreliable.