SPEAKER Andrew Crane-Droesch​ (MS’11) Ph.D. Candidate Energy & Resources Group TITLE 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.