Overcoming Barriers to Solar Dryer Adoption and the Promise of Multi-seasonal Use: A case study of chili drying in India

Abstract

Food and income loss caused by conventional open-sun drying of crops around the world could be reduced by the use of protected solar drying equipment. Yet, solar dryers have not been widely adopted among the majority 470 million smallholder farms worldwide. For dried chili farming in India, over 55% of surveyed farmers reported at least 10% loss of harvest during open-sun drying and quality degradation in 53% of marketed yield. The latter lowered revenue by an average of 34%. Such loss significantly impacts smallholder livelihoods. Employing field data, this paper shows how technical, financial, and operational barriers combine to limit smallholder ownership of common, commercially available hoophouse tunnel dryers with necessary hectare-scale capacities. Because solar dryers are seasonally stranded assets, we assess multi-seasonal revenue streams that incorporate both drying of crops and growing of seedlings. Using service-based operational models to increase smallholder access, such dual use reduces payback time by at least 50% relative to single, drying-only uses. With available financing schemes, multi-seasonal dual-use dryers could reach payback in 1 year compared to 6.5 years for traditional single-use models. A sensitivity analysis of single- and dual-use solar dryer operations is provided and their practical implementation by smallholder farmers is discussed.