While facing increasing challenges in Sub-Saharan Africa (SSA) of climate change, population growth and deforestation, over 700 million people rely on biomass fuels to meet their basic cooking and heating needs. Increasing use of biomass fuels has resulted in negative impacts on the environment through land degradation and deforestation. To overcome problems associated with using biomass fuels, some households in SSA have adopted biogas as an alternative cooking fuel. Use of biogas production technology has led to the development of a number of different biogas appliances. However, these appliances often have low efficiencies; locally made appliances that are affordable and of high quality are needed to support uptake of biogas. In households in Uganda and Cameroon where biogas digesters were installed there was a 52 % reduction in wood fuel consumption, reducing carbon loss by 0.52 (±0.08) t y-1 and deforestation by 0.06 (±0.01) ha y-1 for each household. Water demand was increased by 88 (±25) %, increasing water collection time by 46 (± 13) min d-1. Complete conversion to biogas resulted in a 24 hour mean exposure in households of 18 µg m-3 for fine particulate matter and 0.5 ppm carbon monoxide. However, partial fuel switch resulted in 173 µg m-3 for fine particulate matter which was likely to continue to harm the health of those exposed. Continued use of biogas digesters can reduce the use of wood fuel, but it increases the water demand, which may result in an increase in overall household labor. A new innovation, the slurry separation technology was installed on digesters to reduce labor and water requirements. This significantly reduced (p < 0.05) the volume of water required from 150 (± 25) dm3 d-1 to 30 (±8) dm3 d-1) and household labor from 34 (± 5) min d-1 to 17 (± 3) min d-1.