In 2016, researchers estimated that vaccines would save $544 billion in illness costs and $1.43 trillion in broader economic benefits in GAVI eligible countries alone. According to these figures, immunization programs have the highest return on investment of any development initiative. However, what is often overlooked in the valuing of immunization is the critical role that proper transport and storage of vaccines vis-à-vis cold chains play in this overall value.

To evaluate the inherent social value of a single cold chain unit, two case studies were undertaken. The first case study was conducted by surveying 245 health centres in Kano, Nigeria. The second case study used data on 1,632 solar direct drive (SDD) cold chain equipment from over 5,000 surveys collected across Nigerian healthcare centres.