Andrew Crane-Droesch (MS’11)
Energy & Resources Group
Subsidies, Social Learning, and the Charcoal Dust: Impact and Adoption Dynamics of Biochar in Western Kenya
Sustainable agricultural intensification in sub-Saharan Africa is needed for poverty alleviation, climate change adaptation and mitigation, and in order to meet other growing 21st century pressures. Yet dissemination of agricultural technologies remains a challenge in the region. I report the results of a randomized controlled trial in rural Western Kenya on adoption and impact of biochar, a novel input that can durably improve fertility in poor soils while sequestering carbon. To induce uptake, I randomly assigned subsidies, demonstration plots (aimed at stimulating learning), and deferred payment offers whereby farmers could choose to pay after harvest (aimed at reducing risk and liquidity constraints). In spite of large yield increases on demonstration plots, uptake was rather low. Having a demonstration plot increased odds of adoption by a factor of 3.5, and increasing the share of ones neighbors with demonstration plots from 5% to 10% increased odds of adoption by a factor of 8.5 – an effect equivalent to 53% subsidy. However, given very low uptake at no subsidy, the expected probability of biochar adoption only reaches 50% — at the optimally treated share of the social network — when biochar is offered at 35% of its cost. While social learning can be a tool for technology dissemination, its effects here are conditional on baseline adoption propensity, which is conditional on subsidies. Given uptake well below the social optimum by the end of the project, heavy subsidies appear justified from a social cost/benefit standpoint. Given substantial complementarity with inorganic fertilizer, biochar may be a useful tool for stimulating sustainable agricultural intensification in the region.
Andrew Crane-Droesch does applied empirical research at the intersection of international development and the environment. His goals center on the provision of rigorous evidence to inform policies aimed at enabling sustainable human development in a carbon-constrained and warming world. His PhD work centers on a randomized-controlled trial on the impact and adoption of biochar – a novel agricultural technology with potential to both improve crop yields and sequester carbon – among smallholder farmers in Kenya. Before coming to Berkeley, Andrew worked for the United Nations Development Program. He is proficient in Swahili and Spanish.