Household air pollution from cooking remains a major public health and climate challenge in low-income urban areas. In Kibera informal settlement in Nairobi, Kenya high population density living in poorly ventilated houses, surrounded with poor waste management and use of charcoal in inefficient stoves and kerosene expose people to harmful emissions. This study assessed household energy use, cooking time, and emissions of carbon monoxide (CO), carbon dioxide (CO2) and fine particulate matter (PM2.5) from cooking with charcoal, kerosene, liquefied petroleum gas (LPG), and electricity under real-world conditions, and explored implications for health and climate policy. Participatory cooking tests of breakfast and dinner were conducted in three households that used all four fuel types identified in a household survey. Real-time measurements of CO, CO2, and PM2.5 were taken before, during, and after cooking. Data were analysed using Welch's ANOVA with Games-Howell post hoc tests. Cooking with any fuel resulted into some household air pollution and charcoal and kerosene produced the highest concentrations of the studied gases and particles. LPG and electricity produced low concentrations and there was no significance difference between the two. The household ambient PM2.5 was 213 mu g/m3 implying that people are living in houses with this pollutant being 14.2 times above the 24-h threshold of 15 mu g/m3 by World Health Organization guidelines. Hence no fuel switch alone will address household air quality in the informal settlement. Transitioning households to clean(er) cooking stackings such as with renewable ecooking, improved charcoal cookstoves and LPG scenario showed the highest reduction of emissions contributing toward Kenya's nationally determined contribution of 32% reduction green house gases emission. Clean(er) cooking stacking aimed at net zero should consider sustainable sourcing of the fuel. There is also need for integration of green spaces for air pollutions removal and reduction of emissions from activities such as burning of waste in open spaces, industrial processes and transport.

Gender disparities in science, technology, engineering, and mathematics (STEM) remain pronounced in many African countries, particularly at the postgraduate level. This study explores the experiences of African women in STEM postgraduate education by integrating data from an online survey of 163 female PhD alumni from 40 African universities in 17 countries and seven focus group discussions (FGDs) with 39 current postgraduate students across three countries. Through a mixed-methods approach, we examine both the challenges women face and the factors that enable their persistence and success. Over 60% of respondents reported financial stress during their PhD, and more than half felt unprepared at the time of program entry. Yet 95% expressed confidence in their ability to succeed, reflecting strong self-efficacy despite structural barriers. In the FGDs, women highlighted the burden of caregiving responsibilities, lack of role models, and cultural norms that pressure them to prioritize family over academic careers. Contrary to common assumptions, most FGD participants preferred male supervisors, citing competitiveness or lack of support from some senior women. Despite these obstacles, participants demonstrated high levels of resilience, often driven by a passion for science and strong family support. Our findings highlight the need for family-friendly policies, structured and tailored mentoring, and flexible, gender-responsive institutional reforms to ensure more inclusive and equitable STEM postgraduate environments in Africa.

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.

In Africa the population of refugees is increasing, resulting in ‘accidental urban centres’ often in remote arid landscapes. Firewood and charcoal, the main sources of cooking energy on the continent, are in short supply in refugee settings. This research is based on a series of interrelated studies conducted among Kalobeyei refugee and host communities in Northwestern Kenya using mixed methods from social and natural sciences. Firewood is inadequate, and 95% of households exchanged or sold food to buy cooking fuel. Energy poverty leaves women feeling disempowered and frustrated and causes conflicts between the refugee and host communities. Charcoal briquettes produced and used by the women emerged as a viable cooking fuel. Women stated that marketing challenges and difficulties in sourcing the raw materials may hinder growth of briquettes as a business. Possible solutions include using biomass from the invasive Prosopis juliflora (currently used for charcoal), establishing “briquette kiosks”, and integrating briquettes into development plans. In refugee contexts, approaches to food insecurity should integrate cooking energy and give women an opportunity to voice their needs and aspirations.

Woodfuel that is unsustainably sourced and inefficiently used results in negative environmental and health impacts. This study assessed charcoal use and resultant concentrations of indoor air pollutants (IAP) in an urban informal settlement while cooking with a Jikokoa stove (an improved branded charcoal stove) and medium and small-sized artisanal Kenya Ceramic Jikos (KCJs). Fuel stacking was prevalent with charcoal and kerosene being used by 25% of the studied households. Cooking with a Jikokoa stove reduced charcoal consumption by 6.4% and 26% compared to small and medium-sized KCJs, respectively. The small-sized KCJ reduced charcoal consumption by 21% compared to the medium-sized KCJ. The Jikokoa stove reduced concentrations of carbon monoxide (CO) by 10% and 50% and fine particulate matter (PM2.5) by 6% and 77% compared to small-sized and medium-sized KCJs, respectively. The Jikokoa stove reduced carbon dioxide (CO2) concentrations by 15.6% compared to the medium-sized KCJ. The small-sized KCJ reduced CO and PM2.5 concentrations by 45% and 75%, respectively, compared to the medium-sized KCJ. In summary, small-sized KCJs are more effective than medium-sized ones, and Jikokoa stoves more effective than small-sized KCJs, making it the stove of choice. The more efficient charcoal stoves are, the more charcoal consumption and IAP can be reduced, mitigating environmental degradation, climate change and health problems associated with smoke in the kitchen. There is need for participatory research to scale improved stoves and upgrade local practices as they are cheaper and already embedded in the cooking culture.

In this study, the levels of Al, As, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sr and Zn were determined in 56 composite samples of food aids using inductively coupled plasma mass spectrometry (ICP-MS). It also looked at the potential of food aids on mineral provision for pregnant and lactating women (PLW). The mean mineral contents in cereals were 46.3-378 mg kg-1 for Ca, 24.6-64.4 mg kg-1 for Fe, 2752-4072 mg kg-1 for K, 774-1510 mg kg-1 for Mg, and 14.1-26.1 mg kg-1 for Zn. Cereals presented low dietary significance for K, Ca and Zn as a daily portion (450 g) could only provide between 5% and 69% of Adequate Intake (AI) or Recommended Dietary Allowance (RDA) for PLW. Conversely, corn soya blend (CSB) and pulses appear to play a key role in mineral intakes. However, the existing daily ration for pulses demonstrated little importance to complement dietary K and Ca deficits. Fortunately, Target Hazard Quotient (THQ) values were low enough to guarantee no potential health risks associated with several toxic elements. Overall, it was observed that the food aids do not provide sufficient amount of selected minerals for PLW.

Charcoal is a common woodfuel in sub-Saharan Africa (SSA). Unsustainable wood sourcing and inefficient carbonization result into negative environmental impacts. This action research aimed at building the capacity for sustainable charcoal production including `improving the traditional earth mound kiln (TEK) that is used by 99% of charcoal producers in Kenya. Small stems and branches of the invasive Prosopis juliflora were used and pro-duced quality charcoal with 28 kJ/g which will save trees. Improved earth mound kiln (IEK) increased charcoal yield by 49% per mass of sun dried wood fed into the kiln and reduced emissions of carbon monoxide, carbon dioxide and hydrocarbons by 40%, 49% and 44% respectively. Net charcoal yield by a mass of dry wood in TEK and IEK was 26.4% and 28.4% respectively. Communication and capacity development on sustainable charcoal benefit people and environment. Studies on sustainable charcoal and effects on dryland socio-ecological systems will be needed.

Charcoal and firewood, together comprising woodfuel, are key in the cooking energy mix in sub-Saharan Africa (SSA). Charcoal is made by burning wood under controlled oxygen to arrive at a product high in carbon. Firewood is wood burned directly to provide energy. Wood energy, which is gaining in popularity as a sustainable fuel in developed countries, is characterized as a driver of land degradation on the African continent. Instead of wishing for the demise of woodfuel due to its associated negative health and environmental impacts, a systems thinking approach argues that improving technologies and efficiency in wood production, charcoal and firewood processing, transport and trade, and utilization in a circular bioenergy economy meets a range of needs while conserving the environment. This article outlines a sustainable woodfuel theory of change (ToC) that describes how woodfuel can be made sustainable rather than being dismissed as a transitional fuel on its way out. The ToC is based on the knowledge that no energy system is without flaws and that technologies exist for real quantifiable improvements in woodfuel systems while filling the energy-poverty gap. A bold rational decision must be made in rethinking woodfuel in SSA, as failure to advance woodfuel technologies undermines global efforts directed towards land restoration and climate change mitigation. We recommend that an improved and sustainable woodfuel system should be considered as an acceptable modern energy source under SDG 7.

In Africa the population of refugees is increasing, resulting in ‘accidental urban centres’ often in remote arid landscapes. Firewood and charcoal the main sources of cooking energy in the continent are in short supply in refugee settings. The research is based on a series of interrelated studies conducted among Kalobeyei refugee and host communities in Northwestern Kenya using mixed methods including social and natural sciences. Firewood is inadequate and 95% of households exchanged or sold food to buy cooking fuel. Energy poverty leaves women feeling disempowered and frustrated and results into conflicts between the refugee and host communities. Quality of the briquettes produced and used by the women established their viability as a cooking fuel. Women identified sourcing raw materials and marketing opportunities as challenges that may hinder growth of the briquette as a business. Biomass from the invasive Prosopis juliflora currently being used for charcoal production, establishment of briquette kiosks and integration into the planning and development plans could address these challenges. Strategies addressing food insecurity should integrate cooking energy and gender aspects.

Kitchen gardening is considered a way to reconnect with agriculture and complement the cereal-based relief food offered to refugees in East Africa. This work aimed at profiling mineral content of okra in four refugee camps and settlements located in Ethiopia and Uganda and its contribution to adequate intake (AIs) or recommended dietary allowances (RDAs) for young children and pregnant and lactating women (PLW). The study also evaluated the applicability of portable X-ray fluorescence (PXRF) as compared with inductively coupled plasma mass spectrometry (ICP-MS) for mineral profiling of okra powder samples. The contents of minerals (mg kg −1 ) from the ICP-MS readings were in the following ranges: K (14,385–33,294), Ca (2610–14,090), P (3178–13,248), Mg (3896–7986), Cu (3.81–19.3), Fe (75.7–1243), Zn (33–141) and Mn (23.1–261). Regardless of geographic origin, at low-end consumption probability (17 g day −1 for young children and 68 g day −1 for PLW), okra could contribute ˂ 15% (2.7–12.9%) AI for macro-minerals (K and Ca). In addition, the contributions to RDA values for Fe and Zn, elements of known public health interest, ranged from 4.5 to 34.7% for young children. Interestingly, regression lines revealed strong agreement between ICP-MS and PXRF readings for Mn and Zn, with R 2 values > 0.91. This information is useful in support of nutrition-sensitive kitchen gardening programs through scaling culturally important crops in refugee settings.

In rural Kenya, firewood is used for cooking and heating by 9 out of every 10 households due to its affordability, availability and convenience. This study was carried out using social and natural science methods to understand women's energy burdens and the reasons for the persistent use of firewood. Firewood remains the main source of energy even when multiple fuels are used ("fuel stacking"). Collecting firewood from forests limits women's earning potential and has a negative impact on their well-being although it is a source of income for some as they sell part of what they gather. In these modern times no one would expect that the prospect of freezing to death due to lack of firewood in the tropical highlands worries aging women, but it does. Women's burden of collecting firewood could be lifted by bringing firewood closer through use of residues from trees on farms and burning it in more efficient cookstoves although there may be gender-specific barriers for some women. Income from sale of two timber trees was adequate to meet the cost of labour for pruning trees on-farm and carrying home a year's supply of firewood for families without members who can do the work. This information is useful towards improving rural women's wellbeing and the sustainability of cooking energy. Knowledge gaps still exist in nature, causes and impacts of energy burdens and solutions that work for the people.

Women’s underrepresentation in science, technology, engineering, and mathematics (STEM) impedes progress in solving Africa’s complex development problems. As in other regions, women’s participation in STEM drops progressively moving up the education and career ladder, with women currently constituting 30% of Africa’s STEM researchers. This study elucidates gender-based differences in PhD performance using new survey data from 227 alumni of STEM PhD programs in 17 African countries. We find that, compared to their male counterparts, sampled women had about one less paper accepted for publication during their doctoral studies and took about half a year longer to finish their PhD training. Negative binomial regression models provide insights on the observed differences in women’s and men’s PhD performance. Results indicate that the correlates of publication productivity and time to PhD completion are very similar for women and men, but some gender-based differences are observed. For publication output, we find that good supervision had a stronger impact for men than women; and getting married during the PhD reduced women’s publication productivity but increased that of men. Becoming a parent during the PhD training was a key reason that women took longer to complete the PhD, according to our results. Findings suggest that having a female supervisor, attending an institution with gender policies in place, and pursuing the PhD in a department where sexual harassment by faculty was perceived as uncommon were enabling factors for women’s timely completion of their doctoral studies. Two priority interventions emerge from this study: (1) family-friendly policies and facilities that are supportive of women’s roles as wives and mothers and (2) fostering broader linkages and networks for women in STEM, including ensuring mentoring and supervisory support that is tailored to their specific needs and circumstances.

Biomass fuels dominate the household energy mix in sub-Saharan Africa. Much of it is used inefficiently in poorly ventilated kitchens resulting in indoor air pollution and consumption of large amounts of wood fuel. Micro-gasification cookstoves can improve fuel use efficiency and reduce indoor air pollution while producing char as a by-product. This study monitored real-time concentrations of carbon monoxide (CO), carbon dioxide (CO2) and fine particulate matter (PM2.5), and amount of firewood used when households were cooking dinner. Twenty-five households used the gasifier cookstove to cook and five repeated the same test with three-stone open fire on a different date. With the gasifier, the average corresponding dinner time CO, CO2, and PM2.5 concentrations were reduced by 57%, 41%, and 79% respectively compared to three-stone open fire. The gasifier had average biomass-to-char conversion efficiency of 16.6%. If the produced char is used as fuel, households could save 32% of fuel compared to use of three-stone open fire and 18% when char is used as biochar, for instance. Adoption of the gasifier can help to reduce the need for firewood collection, hence reducing impacts on the environment while saving on the amount of time and money spent on cooking fuel.

Fuel wood is the main source of cooking and heating energy in developing countries. However, it is combusted in inefficient cookstoves, leading to more fuel use and human health problems resulting from exposure to smoke. Thus new, efficient cooking systems that can address some of these problems are required. This study examined gasifier cookstove use in Kwale County, Kenya, and factors influencing adoption. Gasifier stoves were issued for free to 50 households, which were surveyed after 2–3months of use. The results showed that the stove was used by 96% of the households at varying frequencies, 40% of them used it almost every day with 4% switching to only using the new stove. All the users appreciated it because it saved fuel, produced less smoke, and produced charcoal to use for either cooking or soil amendment. Compared with the traditional three-stone open fire, the gasifier stove was reported to be easier to clean (98% of respondents), easier to adjust the heat (88%), easier to handle (58%), caused less exposure to heat (96%) and was cleaner for pots and the kitchen (98%). Another reported benefit of the gasifier stove was that it needed no tending (i.e., adjusting wood and blowing to keep the flames burning). The gasifier stove was mainly used to cook foods that required a short cooking time and many preferred to use it to cook dinner. However, the households encountered some challenges with using the gasifier stoves. For example, fuel preparation, reloading, and lighting were reported as challenges by 42%, 77% and 19%, respectively, of the 83% of households who reported challenges. These challenges could be overcome by improving stove design and by devising innovative ways of cutting fuel into small pieces.

A majority of households in developing countries use biomass energy for cooking and heating due to its affordability and accessibility. However, unsustainable biomass use leads to deforestation, environmental degradation and climate change. The pollution from open burning of biomass is a major health concern especially for women and children as they spend a lot of time in the kitchen. Biochar-producing gasifier cookstoves offer an opportunity to address many of these problems, while also producing biochar, which can be used as a soil amendment. A study was carried out in order to investigate factors influencing the adoption of these cookstoves in three sites in Kenya (Kwale, Embu and Siaya). After an introductory training, 150 households received cookstoves and were asked to use them to produce biochar for upcoming field experiments. User experiences were collected throughsurveys after 2-3 months and about 2 years, and at workshops. The main benefits of the cookstove identified by the users were fuel saving with significant impacts on household economies, reduced smoke and production of biochar for either cooking or soil amendment. Challenges were related to lighting, a need to refill the fuel canister, fuel preparation and different suitability for different typesof meals and meal sizes. The gasifier use frequency and biochar production rates differed between the sites, which had different climate, socio-economic conditions and fuel accessibility. The results will be of relevance for inclusion of user participation in cookstove designing and performance assessment as well as for stakeholders involved in marketing. They can also give guidance on therelevance of gasifier cookstoves for production of biochar for use on farms. (Less)

A majority of people in developing countries use biomass energy for cooking and heating due to its affordability, accessibility and convenience. However, unsustainable biomass use leads to forest degradation and climate change. Therefore, this study was carried out in Kwale County, Kenya, on the use of a biochar-producing gasifier cook stove and implications of its uptake on livelihoods and the environment. Fifty households were trained and issued with a gasifier for free. After 2–3 months of gasifier use, a survey was conducted to investigate the implications of its uptake. The direct impacts included reduced fuel consumption by 38%, reduced time spent in firewood collection, reduced expenditure on cooking fuel, diversification of cooking fuels, improved kitchen conditions and reduced time spent on cooking. The potential benefits included income generation, increased food production, reduced impacts on environment and climate change and reduced health problems. Improved biomass cook stoves can alleviate problems with current cooking methods, which include inefficient fuel use, health issues caused by smoke, and environmental problems. These benefits could contribute to development through alleviating poverty and hunger, promoting gender equality, enhancing good health and sustainable ecosystems and mitigating climate change. The study recommends the promotion of cleaner cooking stoves, particularly gasifiers, among households in rural areas while paying attention to user needs and preferences.

In sub-Saharan Africa (SSA), food security can be influenced by many factors including farmer productivity, access to soil amendments, labor availability, and family incomes (just to name a few). In this paper, we suggest that an additional issue contributes to food insecurity and has been historically absent from the discussion, namely access to cooking energy, particularly for very low income, food insecure individuals. This paper examines the most recent literature that describes the central role played by wood fuels, in particular firewood and charcoal, as a vital, though controversial, source of fuel used by the vast majority of rural and urban sub-Saharan Africans. We explore the reality that although the health risks of collecting and using firewood and charcoal in traditional manners are real, policy makers, researchers, and donors need to address the sustainability and viability of the current fuel types used by the majority of people. We end the paper with a series of practical suggestions for improving the wood fuel systems as they currently exist in the region.

Traditional development models assume that countries of the Global South will undergo an economic trajectory roughly equivalent to that of the Global North. The reality of climate change caused by the burning of fossil fuels raises the prospect that a new model, founded on renewable and sustainable energy will have to be designed. At the same time, rural locations in North, face devastating economic consequences of an industrial model that has left them behind. Our international, transdisciplinary research team, working in Eastern and Southern Africa on sustainable biomass energy and in New Kensington, PA on rural small town renewal, seeks to understand the intersection of community preferences, technological innovation, gender relations and environmental sciences to develop socio/technological interventions. We flip the development model, bringing African expertise to bear on US-based problems and US-based insights to understand subculture specific cultural preferences in Kenya. This presentation outlines how we work together, the methods we use to engage in creative problem solving and the unique “kitchen laboratory” used on the Kenyan side to assess cooking energy needs.

Resource Recovery and Reuse (RRR) is a subprogram of the CGIAR Research Program on Water, Land and Ecosystems (WLE) dedicated to applied research on the safe recovery of water, nutrients and energy from domestic and agro-