Build a Cold Chain Solution for Tomato Farmers in Kaduna

Kaduna State is one of Nigeria's largest tomato-producing zones, but farmers regularly lose half their harvest to spoilage between the farm gate and the market. Refrigerated trucks are expensive, unreliable power makes cold storage impractical, and most aggregators are informal with no fixed logistics chain. The losses hit women traders and smallholder farmers hardest. Your task is to design a cold chain model that works within these constraints. You are not designing for a world with stable electricity or easy capital. You are designing for a tomato farmer who earns under 200,000 naira a month, sells through a local aggregator, and cannot afford to lose two harvests in a row. Produce a business model document and a one-page visual schematic of your proposed solution. The business model should cover: the technology or method you are recommending (evaporative cooling, communal cold rooms, insulated crating, or something else), who owns and operates each part of the chain, how costs are shared or recovered, and what the farmer actually pays. Include a simple financial model showing unit economics at small scale. Good work will be grounded in real constraints. It will name specific technologies that already exist and have been tested in West Africa or comparable markets. It will not assume grant funding as the primary revenue source. A strong submission will also identify the single biggest point of failure in the model and explain how it is mitigated.