CCooling technologies and long-term efficiency improvement of horticulture market agents: Panel data evidence from a solar-powered cold storage intervention in Nigeria

Modern cooling technologies that use renewable energy sources have been increasingly recognized as a promising tool to address a multitude of challenges emerging in progressively complex food systems in developing countries. When provided as cold storage inside horticulture markets, cooling technologies can contribute to improved quality of products and strengthened vertical linkages. Knowledge gaps about the medium- to long-term impacts of these technologies in developing countries remain, especially in Africa south of the Sahara (SSA). This study partly fills this knowledge gap by revisiting the 2021 short-term impact evaluation study (Takeshima et al. 2023) to assess the medium- to longer term impacts of interventions in northeast Nigeria in which 7 small solar-powered cold storages were installed across 7 horticulture markets. Combinations of difference-in-difference and variants of propensity score-based methods suggest that using cold storage significantly increased horticulture sales volumes and revenues of market agents. Using cold storage also reduced the share of food loss and lengthened the products’ shelf-life while raising prices received by both market agents and farmers, which were associated with improved product quality, expanded value-adding activities by market agents, and increased use of advance payments. We find no evidence of negative spillover effects inside horticulture markets. Observed effects are driven by the technical improvements that raise the efficiency of the use of purchased raw commodities, enabled by cold storage, based on modified efficiency analyses. At the same time, the efficiency of cold storage use remains low despite some improvement over time, and scopes exist to enhance this efficiency.