Biogas-fuelled refrigeration system as a pathway to reduce post-harvest losses in Sub-Saharan Africa: A feasibility evaluation

Abstract

Different process scenarios for biogas-fuelled refrigeration (BFR), to curb food loss in Sub-Saharan Africa by providing off-grid refrigeration, were compared in terms of techno-economic feasibility. Technical simplicity was a key consideration in the selection of four biogas-fuelled refrigeration options, i.e. (i) absorption dairy coolers for smallholders, (ii) containerized cool rooms for small-scale produce value chain actors, (iii) industrial icemakers for small-scale fish value chain actors, and (iv) combined heat and power (CHP) systems for the electrical requirements of refrigeration for abattoirs. Using discounted cash flow analysis, internal rates of return ranging from 15.13 % to 28.16 % (absorption cooler), −6.77 % to −2.79 % (CHP), 0.97 % to 22.84 % (cool room), and 0.74 % to 24.05 % (icemaker plants) were estimated. The absorption dairy chiller had the best techno-economic feasibility, particularly at the smallest scale (45 L refrigerator). The high feedstock requirements for the ice maker and the cool room processes could cause operational challenges, as they are less cost-effective than alternative solar-powered options. The abattoir CHP could provide sufficient electricity to cover refrigeration demands, although the levelised energy costs (heat and electricity) were not competitive. Implementing BFR in small-scale agricultural value chains requires financing upfront capital costs, efficient equipment operation and maintenance, and the supply of process water.