A majority of households in sub-Saharan Africa use inefficient biomass stoves in poorly ventilated kitchens, leading to indoor air pollution. Biomass for cooking can be sustainably sourced from agricultural residues such as prunings from agroforestry. This study assessed biochar-producing gasifier cookstove performance among 150 households in Embu, Kwale, and Siaya Counties through household surveys and participatory cooking tests with 75 households. With the gasifier, carbon monoxide (CO) concentrations were lower in Embu (5.1 ppm), while carbon dioxide (CO2) and fine particulate matter (PM2.5) were lower in Kwale, at 588 ppm and 136 μg/m3, respectively. Compared to the three-stone open fire, reductions in CO and PM2.5 concentrations were highest in Embu, at 82% and 97%, respectively. The biomass-to-char conversion efficiency with the gasifier was 17–18%. If households consider the produced char as a soil amendment, they could save 24–43% of fuel compared to the three-stone open fire; if the char is seen as fuel, the potential savings are 42–65%. Significant differences between the three sites were observed with the gasifier for gross and net fuel use, and for concentrations of PM2.5 and CO2. Gasifier uptake can reduce the need for fuel collection and indoor air pollution, with a positive impact on both the environment and human wellbeing.
Tag: cookstoves
A quantitative performance assessment of improved cooking stoves and traditional three-stone-fire stoves using a two-pot test design in Chamwino, Dodoma, Tanzania
How to increase cookstove adoption? Exploring cost-effective dissemination techniques in Central Mozambique
The adoption and usage of improved cookstoves have been promoted in the Global South to mitigate the adverse effects of relying on solid biomass for cooking. However, the uptake and continued use of improved cookstoves remain low. Several behavioral changing techniques have been used to increase the adoption of improved cooking stoves. Still, the monetary costs involved in the dissemination process are generally neglected, and few studies follow an experimental design to evaluate the impact of different stove dissemination approaches. Thus, we conducted an experiment to explore the cost-effectiveness of dissemination approaches and measure their effect on improved cookstoves adoption in Central Mozambique. Forty communities were randomly assigned to receive one of the following treatments: (1) individual video training, (2) on-site group training or (3) a combination of both. In total, 620 households we randomly selected from the 40 communities to participate in the study and 510 were included in the final analysis. The rates of adoption within each treatment were 53 % for individual video training, 21 % for on-site group training and 47 % for the combination of both. The monetary training costs were lower for individual video training, which stimulated the early and sustained adoption of improved cook stoves. Our findings provide strong evidence that the tool used for capacity building affects the adoption of improved cookstoves. Extension agencies should be aware of cost-effectiveness and adjust dissemination approaches to achieve the highest impact per unit of resource expenditure.
Utilizing Mathenge (Prosopis Juliflora) for Charcoal: The Other Side of an Invasive Species
The study used Focused Group Discussions (FGD), seasonal and livelihood calendars, participatory visioning and mapping and training of trainers delivered in partnership with KEFRI. Analysis from the project has showed that the species has potential to provide communities with 14 different products and services with charcoal ranking highest and food for humans the lowest. In terms of contribution to livelihoods, both men and women rank charcoal among the top three livelihood sources after farming and livestock keeping. Pods, another product from Prosopis can be sold as feed for livestock at KES 100 (USD1) per 50kg bag. Management by utilization of the almost 19,000 hectares of Prosopis juliflora in Baringo for sustainable charcoal production presents potential for improving livelihoods and the environment. It presents an opportunity for supplying the growing urban centers with affordable cooking fuel, a strategy that can be scaled out to the other affected counties. Also, there is need for complete removal of mathenge in some pockets to create room for enrichment with native high value multipurpose tree species to enhance biodiversity.
Biochar from cookstoves reduces greenhouse gas emissions from smallholder farms in Africa
Biochar produced in cookstoves has the potential to contribute to negative carbon emissions through sequestration of biomass carbon while also providing other benefits for sustainable development, including provision of clean renewable energy and increased yields in tropical agriculture. The aim of the reported research was to estimate effects on food production, household energy access and life cycle climate impact from introduction of biochar-producing cookstoves on smallholder farms in Kenya. Participatory research on biochar production and use was undertaken with 150 Kenyan smallholder farming households. Gasifier cookstove functionality, fuel efficiency and emissions were measured, as well as biochar effects on agricultural yields after application to soil. Cookstoves provided benefits through reduced smoke, fuel wood savings and char production, but challenges were found related to labour for fuel preparation, lighting and refilling. On-farm trials with varying rates of biochar inputs, in combination with and without mineral fertilizers, have led to a sustained increase of maize yields following one-time application. The climate impact in a life cycle perspective was considerably lower for the system with cookstove production of biochar and use of biochar in agriculture than for current cooking practices. Climate benefits from biochar production and use are thus possible on smallholder farms in sub-Saharan Africa, through reduced use of biomass in cooking, reduced emissions of products of incomplete combustion and sequestration of stable biochar carbon in soils. Biochar-producing cookstoves can be implemented as a climate change mitigation method in rural sub-Saharan Africa. Successful implementation will require changes in cooking systems including fuel supply, as well as farming systems, which, in turn, requires an understanding of local socio-cultural conditions, including power relations and gender aspects.