Economic and environmental impacts of domestic bio-digesters: Evidence from Arusha, Tanzania

Despite substantial programmatic investment in domestic bio-digesters across sub-Saharan Africa in recent years, little empirical evidence has been published regarding the existence or magnitude of socioeconomic or environmental benefits accruing from bio-digester implementation. A cross-sectional study of 40 households in Arusha, Tanzania, suggests that bio-digester adoption has the potential to reduce fuel-wood use, energy-related expenditures, and time-costs of energy procurement; to lower CO(2)e emissions; and to increase farm incomes. No significant differences in synthetic fertilizer use were observed between households with and without bio-digesters. Domestic bio-digester investments were found to have a positive net present value across a wide range of discount rates. Further, we estimate that domestic bio-digester implementation at the country wide level in Tanzania could potentially access $80-$1.15 million annually in carbon emissions reduction (CER) financing through the Clean Development Mechanism. (C) 2013 International Energy Initiative. Published by Elsevier Inc. All rights reserved