ETHOS 2025
January 24-26 2025

Insulating 100% ceramic rocket stoves are highly energy efficient giving no smoke and meet squarely the SDG7 stipulation of affordability. The volume of voids is 50% so the stove is highly insulating and lightweight. Following is a link to a video that shows our insulating rocket stove in Rwanda. The stove boils water quickly, using remarkably little biomass fuel, i.e., leaves and sticks in the video. Because the stove is 2-piece, cook pots of any size can be used. When produced by rural potters the stove will pay for itself quickly for the poorest, in the savings of time and money. Boiling for water treatment could be affordable.

After five years of development of climate-friendly food processing with the Chitofu-type technology family, we are now entering the off-grid baking space. Get the update how this unique technology concept developed first in Malawi for climate-friendly fish processing continues to expand into more countries and diversify according to user’s needs regarding size and mobility.
Find out what has happened since ETHOS 2024 when we last presented.

Current evidence from observational studies on the impact of ambient air pollution on cardiometabolic outcomes, such as inflammation and blood pressure levels, shows a generally
positive trend; however, there is minimal and inconsistent evidence of the health effects of HAP
in LMICs.
In this presentation, I will be sharing findings from two randomized controlled trials conducted in
rural Honduras and Rwanda, respectively. From these RCTs, we have sought to understand the
impact of improved biomass stove intervention and HAP-related fine particulate matter and
black carbon exposures on the inflammation and blood pressure levels of participants across
different demographic profiles.

Paris Agreement's Article 6 facilitates carbon markets and carbon finance to support eligible climate mitigation programmes, such as cleaner cooking activities globally. Accessing specific markets such as the aviation offsetting programme, with a price premium, requires meeting an international standard, such as Gold Standard, getting a letter of authorisation from the host country and finally getting insurance for breach of contract or having the host country confirm the corresponding adjustment in their biennial transparency report.
Sounds complex, how can we simplify this process to assist cleaner cooking programmes access better priced markets?

Top Lit Updraft (TLUD) Gasifier cookstoves, are known to experience flame-out, when, due to an upset condition, the combustion process is interrupted, while the gasification process continues. Although this is known to be a characteristic phenomenon with TLUD Gasifier cookstoves (TLUDs), we are not aware of any published test results documenting the CO generation rate. The published literature does indicate that wood gas includes 20 – 30% carbon monoxide. For this piece of work, three different TLUD stoves were tested, by establishing the normal gasification & combustion process and then extinguishing the flame with wind from an external blower. The test results show that CO emissions from the TLUD during flame out can be more than 10 times higher than the emissions from a primitive charcoal stove. Potential CO exposure in a kitchen was calculated by matching different air exchanges with the CO generation rate. This evaluation indicates that for an uncorrected flameout, where the gasification process continues, the CO exposure to persons in the room could be quite dangerous.
Flame stability, as indicated by the resistance to flameout from wind, was measured for one stove design feature - different pot support heights.
Recommendations are made for 1) for lowering the risk of user exposure to CO from flameout and 2) follow-up testing and analysis.

This talk covers a collection of ideas related to stoves. These include using minimally processed wood as a substitute for charcoal, the use of modified skirts that allows the cook to easily see the fire while still protecting the fire from wind and increasing efficiency, the desirability of batch-loaded stoves that require no tending once the fire is started, and the use of a cone-shaped pot support to firmly hold the pot in place. Other ideas for a desirable stove will also be included. Information from at least 3 previous ETHOS presentation will be presented, as a way of drawing upon some of the rich history of ETHOS presentations.

Shengzhou Stove Manufacturer has sold over 6 million Rocket stoves and has been improving cleaner combustion stoves for sale including forced draft TLUDs and Jet Flame applications. Mr. Shen with his staff of engineers and Aprovecho have collaborated on increasing turn down ratio in FD TLUDs with primary and secondary air, decreasing Black Carbon ratios, and applying Jet-Flame technology to low cost applications. A 9 minute video shows new machines at SSM and the new biomass heating stove buildings.

The abstract emphasizes the evolving landscape of clean cooking initiatives, highlighting the shift from traditional financing mechanisms focused solely on fuel savings and emissions reduction to a more integrated approach considering market dynamics, standards, and design. While global interest in clean cooking is driven by climate change and user convenience, effective financing now requires a balance between technical reliability, market forces, and user acceptance. The introduction of the ISO 19867-1:2018 standard represents a critical step forward, though it underscores capacity gaps in laboratory testing and equipment that must be addressed. Recognizing that standards alone are insufficient, the blueprint for clean cooking financing advocates a harmonized framework that integrates design, market considerations, and user-centric approaches, enabling sustainable adoption and impactful innovation in the clean cooking sector.

The health and economic costs of inhalable particulate matter (PM) are well established and have led to the establishment of air quality standards in many jurisdictions. Compliance with these standards is typically monitored using specialized equipment operated by highly skilled personnel. However, these regulatory systems often do not provide air quality measurements that accurately represent an individual’s current exposure to PM. As a result, there is a growing demand for low-cost air quality monitoring systems that can provide timely and accurate measurements of personal exposure to both fine and coarse PM.


Optical particle counters (OPCs) are widely used low-cost devices for monitoring individual, real-time exposure to PM. However, the precision and accuracy of the data generated by these devices need to be verified. This presentation will describe simulations of particle-laden flows through various geometries. The results of these simulations are used to rigorously define performance metrics. The OPC sampling factor quantitatively assesses how well the concentration and size distribution of PM entering an OPC represent the concentration and size distribution in the ambient air. The OPC detection factor evaluates the representative difference in concentration between the inlet and the detection region of an OPC as a function of the aerodynamic diameter of the particles. These performance metrics can be used to assess the performance of real OPCs.

In the history of Improved Cookstoves (ICS), countless initiatives worldwide promoted production and (commercial?) distribution of ICS based on “individual tinsmiths sitting under a tree producing 1-2 ICS per day” . These approaches based on local production&resources for local clients can be valuable in local cases.
Recently we mainly report either on human health or climate impact, or both. ICS have not much to contribute to the WHO Health agenda. Even for climate change mitigation, the local ICS cottage production cannot give a significant contribution. The individual ICS reduces the specific fuel use just on a limited increment, is not always used (stacking), and the reductions can only be applied to the non-renewable part of the used biomass etc.
Climate friendly ICS therefore can only contribute significantly to national mitigation targets if they are covering most of the population (“universal access”).
But how do we get from local artisanal ICS production to universal access?
Christoph will summarize 20 years of experiences of ICS Sector transformation in Senegal supported by EnDev/GIZ work under various donor support (BMZ, EnDev donors, EU, GCF).
Learn how large-scale transformation is feasible in the right conditions with appropriate funding and time. Don’t attend if your main focus is only health or carbon markets. This one is on “old school” technologies combined with new approaches, focusing on climate, environment, poverty reduction and employment.

`Insulated Solar Electric Cookers (ISEC) utilizes solar electricity, insulation and thermal storage, providing an inexpensive, environmentally friendly, culturally adaptable alternative to traditional cooking.
After developing phase change thermal storage, we now use Solid Thermal Storage (STS) for reasons of simplicity and safety.This presentation focuses on using aluminum for STS due to its thermal properties and availability, the risks of recycled materials, and potential use of concrete for structural components. We were able to achieve a thermal power transfer of around 600W for the first 320kJ of transfer with the STS heated to 250℃.
We are developing ISEC fortuitously as the cost of solar panels is drastically falling amid global initiatives to expand access to solar electricity for underserved populations.

Determining particulate mass (PM10 or PM2.5) in stove emissions is complex due to the dynamic formation and evolution of particulates during combustion. Effective sampling of combustion gases is crucial to avoid artefacts in particulate mass measurements, such as the growth of particles by water vapour or semi-volatile compound condensation or loss. Isokinetic sampling and laser particle counters, which depend on light scattering and assumptions about particle density, are routinely used for measuring particulate mass. Many labs also use particulate filters to collect particles for subsequent gravimetric mass calibration. At North-West University, a novel approach utilises a continuous sampling instrument that employs dry nitrogen gas injected transversely to the gas flow to induce venturi-like dilution of combustion gases. This method captures a diluted and cooled stream, halting further particle evolution. Research is being conducted on a beta-gauge mass monitor as a potential alternative to laser instruments, emphasising its property of being based on fundamental physical principles. However, it has a lower sampling frequency. The complete design specifications of the dilution device and details of all instruments will be shared with the stove testing community.

La implementación de EML ha sido esencial en la reducción del uso de biomasa y la mejora de la calidad del aire en zonas rurales. Sin embargo, se requiere una mayor transparencia y control sobre su desempeño en campo para maximizar su impacto en los ODS.
El TRADEC permitirá obtener y manejar de manera remota la información de desempeño de las EML mediante tecnologías electrónicas, análisis de datos, software y hardware. Identificar las oportunidades de interacción para los usuarios con sus EML y la ampliación del espectro de involucramiento a nuevos ODS.
A través del TRADEC se podrá transmitir datos de funcionamiento de las EML, lo cual permitirá la evaluación de datos de funcionamiento en tiempo real y su transmisión automática, liberando a los operadores de la verificación en campo.
El TRADEC permitirá a las EML transmitir datos de operatividad, eficiencia y supervivencia directamente a los sistemas de control, reduciendo la carga logística y mejorando la validación del uso. Proporcionará, a través de software estadísticos, análisis avanzados y proyecciones de escenarios, optimizando la eficiencia y el impacto en la matriz energética generada por biomasa.
La incorporación de tecnologías avanzadas en la monitorización de las EML abre nuevas oportunidades para su control y mejora continua. Estas innovaciones no solo aumentan la eficiencia operativa, sino que también validan su contribución a los ODS, promoviendo un desarrollo más sostenible y eficiente en el uso de biomasa.

To support capabilities in stove testing centers globally, Aprovecho Research Center has developed three open-source computer applications for analysis of stove test data from the lab and field. The apps make it easier to process and compare test data while reducing errors, increasing shareability, and making it easier to generate knowledge for R&D. The apps and code are open-source and version controlled on Github, adding transparency to the functions and calculations of the apps while inviting users to view and suggest changes, and allowing easy distribution.
The software reduces processing errors by implementing a flag system that notifies the user when inputs or results are outside the expected range. It increases shareability by standardizing outputs and including a button within the app that will share data.
The three apps work together to allow for the user to view the results of a single test (level 1), multiple tests from the same stove (level 2), and compare different stoves or configurations (level 3). The level 3 analysis allows for a detailed overview of a stove developer’s portfolio, providing an easy comparison for various on the market stoves, and a simple way to compare iterative designs changes during R&D.
The app has already been launched in select Regional Testing and Knowledge Centers globally for user testing and feedback with the goal of releasing it soon to all labs and expanding its capacity to analyze results from different emission testing systems.

In this research, an uncontrolled cooking efficiency test (UCET) was developed and implemented to measure baseline efficiency and fuel consumption in the field. In partnership with researchers in Ghana, Malawi, and Kenya, a series of UCETs were conducted in 80 households for 3 meals each for a planned total of 720 tests. Results from the UCETs show overall average thermal efficiencies of 11.8 ± 5.3% for traditional wood and 22.1 ± 9.8% for traditional charcoal cookstoves, demonstrating good agreement with the previous and current UNFCCC baseline values of 10% (now 15%) for wood stoves and 20% (now 25%) for charcoal stoves. Single meal fuel use was extrapolated to an annual household fuel consumption of 0.17 ± 0.07 tonnes per capita for wood and 0.04 ± 0.02 tonnes per capita for charcoal are conservative compared to the UNFCCC baseline for woodfuel of 0.5 tonnes per capita. Multiple regression analysis was performed showing a strong statistical association with firepower for both types of stove, and suggests that pot/pan dimensions influence wood stove efficiency while cooking method is influential on charcoal stove efficiency. The results demonstrate the utility of the UCET for evaluating cookstove efficiency and fuel consumption in households at the implementation stage to more accurately support funding allocation.

Upstream emissions from charcoal production are significant in the accounting of carbon emission reduction programs. The current UNFCCC default value for the conversion factor from wood to charcoal is 4 kg of wood (wet basis) to 1 kg of charcoal, reduced from a previous value of 6 kg/kg. These defaults do not account for additional losses along the supply chain. To establish and expand values of the wood to charcoal factor when also accounting for losses of useful and non-useful energy along the full supply chain, a Charcoal Value Chain Conversion Factor Measurement Protocol was developed by Aprovecho and implemented by a team of researchers in Ghana and Malawi. Measurements were conducted on 12 kiln runs in each country, and included kiln conversion factors, losses in the distribution, transportation, and household stages, in addition to quantification of wood harvested from the forest or farm that was not ultimately placed into the kiln. The average wood to charcoal conversion factor measured between the kiln input and output in Malawi was 7.3 kg of wood (wet basis) to 1 kg of charcoal (dry basis), and 6.9 kg/kg in Ghana. These values are close to the previous UNFCCC default of 6 kg/kg but further from the newer conservative value of 4 kg/kg. However, as the system boundary expands to account for all mass lost during harvesting, transportation, and distribution, the conversion factor increases to 9.6 kg/kg in Malawi and 13.0 kg/kg in Ghana (11.0 kg/kg overall).

ISO (International Organization for Standardization) standards are reviewed every five years, and the ISO 19867-1:2018 cookstove laboratory testing standard is currently undergoing review and revision. This presentation will provide an update on proposed changes, implications for performance ratings, and next steps in the process.

SNV Ethiopia is implementing Result- based Financing (RBF) based project to incentivize the clean cooking enterprises for its cooking solutions production and marketing, made contingent on the delivery of a pre-agreed results through an independent verification.
Our major objective is to scale-up the commercialization of higher-tier cookstove technologies, to reach rural, urban, and peri-urban areas by scaling-up existing, and fostering new higher-tier cooking enterprises to enhance the supply-side businesses by improving accessibility of clean cookstoves and fuels.
Establishing and implementing an innovative financing mechanisms like RBF will overcome product quality issues, market barriers, foster employment, contribute for GHG emission reduction and address Gender Equality and Social Inclusion (GESI) gaps.
To achieve the above objectives, we were developed RBF operational manual, establishing business to business support services and other implementation methodologies.
Now we are working with 9 potential RBF enterprise and which sold more than 5000 clean cooking solutions for the end users, and it is under independent verification to facilitate incentive payment. Beside these we are on process for second RBF call.
These all will make the audience to be interested, and they will learn the practical experience of RBF implementation process, governing issues, data monitoring and verification mechanisms, and its opportunities and challenges.

Recent studies and corresponding media attention have raised concerns, particularly regarding childhood asthma, over exposure to gas stove emissions. This study assessed air quality in homes participating in an electrification program vs. comparable controls. Program homes, which received induction stoves to replace propane-fueled appliances, were low-income rural households off the natural gas grid. A total of 139 participants were selected from program-eligible homes, with 72 homes receiving electric stoves and 67 homes using propane for cooking. Each home was monitored for PM2.5, NO2, NOx, and CO for one month, complemented with ambient PM2.5 measures. Real-time stove and venting hood usage was also measured to characterize their direct impact on pollutant concentrations. NO2 concentrations in electric stove homes were 67.6% lower (p<0.001) compared to gas stove homes (6.6 vs. 20.4 ppb). Compared to the WHO NO2 guideline of 5 ppb, 63.2% of electric homes and 98.4% of gas homes had higher concentrations. PM2.5 levels showed minimal differences, aligning with expectations that gas stoves emit negligible PM2.5. These findings suggest that this electric stove program lowered indoor NO2 levels to near WHO guidelines. This adds to the growing evidence of the air quality benefits of household electrification, particularly in rural settings. However, there is still a need to understand how programs can be targeted and structured equitably to benefit populations most in need.

How can we systematically study cultural influences on program design and reception? Design Anthropology provides a framework for observing and analyzing cultural elements to generate qualitative data that informs design. This session demonstrates how ethnographic research sprints focused on specific themes can offer valuable insights to guide design and enhance communication with staff, recipients, and stakeholders.
In StoveTeam International’s programs in Retalhuleu and Totonicapán, Guatemala, Design Anthropology was used to explore local concepts of trust and their role in empowering key actors and institutions. Recipient Journey Maps visualized the stove-receiving process from participants' perspectives, highlighting moments of insecurity and identifying the trusted actors most critical to stove purchase, receipt, and adoption, along with the sources of their trustworthiness. This provided a deeper understanding of local trust systems, which can inform the consideration of new initiatives and design changes. This session encourages you to reflect on your organization's approach to understanding and describing the cultural contexts of your programs and explore how culture-centered design can be leveraged to study themes critical to your program’s success.

Ethiopia, with a population exceeding 120 million, is at a critical juncture, transitioning from improved cookstove interventions to higher-tier clean cooking technologies—essential for achieving SDG 7 and ensuring universal energy access. This shift requires more than technological advancements; it demands a comprehensive approach that integrates technological readiness, user-centered design, and socio-cultural integration.
This presentation explores Ethiopia's efforts to scale higher-tier clean cooking solutions, focusing on efficiency, affordability, fuel availability, and safety, while addressing the unique needs of diverse communities. A key aspect is understanding Ethiopia’s socio-cultural diversity across rural and urban settings, considering traditional cooking practices, fuel preferences, meal preparation habits, gender roles, and cultural beliefs.
Ethiopia’s experience underscores the importance of behavior change communication and culturally tailored messaging. The presentation will showcase a project that sensitized over 8,000 buyers in 8 months. This will provide insights into strategies for advancing clean cooking solutions, addressing social and cultural nuances, and ensuring technology adoption in marginalized communities. The motto "No one left behind, no one dies because of cooking" underpins Ethiopia's commitment to reducing the silent killer in the kitchens of millions of women and children. However, this ambition can only be realized through action.

The increasing concerns surrounding household pollution from the use of biomass fuel have highlighted the need for sensors capable of accurately measuring the mass concentration of pollutants. One major pollutant of interest is particulate matter (PM) due to its significant risks on both human health and the environment. Low-cost optical particle counters (OPCs) are widely available for use to measure PM concentrations by both individual and organizations. These devices operate based on the scattering of light by particles. However, these instruments have limitations, mostly attributed to their design and the choice of the location of the detection region (DR) where the PM concentration is measured. The selection of the DR is critical, as the performance of low-cost OPCs is characterized by the particle concentration in this region. This research focuses on using two computational fluid dynamics packages (ANSYS Fluent and CONVERGE Studio) to assess the performance of a simple geometry and a commercial OPC. Analysis was performed for various DRs by assessing concentration variations and an OPC detection factor performance metric, which compares the DR concentration to that of the inlet of the OPC. Results from the simulations demonstrated that DR placement significantly impacts measured particle concentration and OPC performance.

This presentation introduces a methodology that integrates black carbon (BC) and organic carbon (OC) emissions into digital metered carbon accounting for clean cooking projects. BC significantly contributes to climate change and health risks but remains underrepresented in current carbon credit systems. This project, a collaboration with Modern Energy Cooking Services (MECS) and funded by the Foreign, Commonwealth & Development Office (FCDO), leverages digital monitoring, reporting, and verification (dMRV) technologies will enhance transparency, efficiency, and accuracy in emissions accounting. By employing field-based emission factors and lessening depending on laboratory testing, the methodology will better represent real-world impacts compared to previous approaches. The session will highlight how reducing BC emissions not only mitigates climate impacts but also generates substantial health co-benefits, including reduced exposure to harmful particulate matter. Furthermore, digital methods enable detailed tracking of project impacts, creating new opportunities for results-based financing (RBF) and making clean cooking projects more attractive to investors by ensuring measurable, verifiable outcomes. Attendees will gain insights into how this methodology combines digital tools, collaborative expertise, and a focus on actionable impacts to address climate, health, and sustainable development challenges.

The Comprehensive Lowered Emissions Assessment and Reporting (CLEAR) Methodology for Cooking Energy Transitions is a new methodology for crediting emissions reductions from cookstove projects developed by the Clean Cooking and Climate Consortium (4C), in collaboration with Atmosphere Alternative. It is the first methodology to cover all common cooking transition scenarios and incorporates the latest science on key parameters, increasing the requirements for substantiating the input parameters that have the most impact on emission reduction estimates​, including mandating direct in-home measurement of fuel consumption​. By using this methodology, clean cooking carbon projects will generate realistic emission reduction estimates and reduce integrity risks. During this panel discussion, the audience will learn more about the latest version of the CLEAR methodology, which has already been submitted for review and approval to recognized carbon-crediting programs.

Smokeless Chimney is a leader in smoke measurement and wood stove control technology. We recently won a grant from the Department of Energy (DOE). We are working with a team of scientists to measure smoke from solid fuel devices on a new level. Smokeless Chimney has 3 patents, the technology and experience to measure smoke as a hot gas down to particles of 100 nanometers and opacity to 0.1%
Today in 2024 there are 13 million wood stoves solid fuel appliances in use in the USA alone and many more outside the USA. Normally located in the northern states where wood supply is good, cold weather is common, power costs are high and storm caused electrical power interruptions can result in dangerously low house temperatures. Think not for the human and pet occupants, think of the water in the pipes freezing and cracking the pipes.
How can we do better? What is the current technology to measure smoke?
Smokeless Chimney technology includes projecting a white light through the smoke and measuring small changes in incident light and color. The incident light results in opacity measurement and a shift in color is a result of Tyndall Scatter scattering only the blue light when particles are smaller than the peak wavelength.


Www.smokelesschimney.com

Since 2018, Climate Solutions and Oregon State University have been working on automating the measurement of fuel consumption in the field. Today, the FUEL data-logging scale is used in large scale measurement campaigns for research and carbon projects. Digital sensor-based KPT addresses some of the issues with regular KPT, but it also comes with its set of challenges.
We will present in this session the lessons learned from 6 years of research and development on this topic and highlight best practices for successful deployment. We will also highlight current area of research.

Sixteen years ago, at a workshop in Hidalgo, Mexico, Larry Winiarski taught me that using a homemade retained heat container to simmer food (using no fuel at all) was far less expensive and more reliable than making a biomass stove with a simmer function.

Larry argued that such a stove would cost more to purchase, would eventually break down and would then need repairing, if repair was even possible by the people using the stove.

In this presentation, I will explain in detail what I learned from Larry about building biomass stoves and retained heat containers, and why I encourage the ‘stover’ community to consider promoting the use of retained heat containers for simmering rather than trying to install a simmer function in biomass cookstoves.

Much to Larry’s delight, I filmed his 2008 rocket stove demonstrations in Mexico and the following year, turned them into the first two videos (“How to make a 16-brick Rocket Stove” and “How to Make a Tin Can Rocket Stove”) on my new You Tube Channel “Solarwindmama”.

Larry was thrilled when he saw the videos since no one had ever filmed him teaching people how to make rocket stoves. He was even happier when I told him a few years later that more than 859,000 people had watched those two videos. He was a truly inspiring guy with a great sense of humor. It was an honor to be his friend.

The Clean Cooking and Climate Consortium (4C) has developed a harmonized carbon accounting framework that builds on current methodologies used in the voluntary and compliant markets. Previous concerns of over-crediting from emissions reductions in existing methodologies created an opportunity to be more prescriptive about appropriate default values and ranges for key parameters. This project compares previous methodologies to the CLEAR methodology, exploring different values of fNRB, energy consumption, adoption and upstream emissions. This talk will show the differences between the CLEAR methodology and previous methodologies in four example clean cooking projects.

I spent the 2022 – 2023 academic year visiting (MECS/UKAID supported) collaborating enterprises with whom my students and I have been developing Insulated Solar Electric Cooking (ISECooking) since 2015. Each area in 7 African countries, India, and Nepal has unique manufacturing capacities as well as challenges stemming from differences in education, access to imports, local infrastructure, and local culture. I learned unique construction techniques in each place that I was able to share in subsequent locations. In Malawi, we studied how local women cook with firewood, and we established two vocational ISECooking programs that are still running. In Nepal, a factory is now producing ISECookers… maybe. I will ask for your help to identify next steps, as I plan another year.

Since 1976, Aprovecho has been building global capacity for cookstove testing and design and currently distributes emissions testing equipment that is used to understand performance in the lab and field. This talk will present three case studies to demonstrate Aprovecho’s recent work enhancing testing and design capacity at Regional Testing and Knowledge Centers with the goal of creating accessible solutions to protect health and climate: 1. Institutional stove at CSIR Ghana, 2. Local manufacturing at EGA South Africa, 3. Cordwood heating stove for US markets. In all cases a design is conceptualized based on past experience and is bound by market demand, the design is communicated to builders and stakeholders, and tests are performed in the lab and field to measure success. The case study in Ghana revealed that there is demand for sunken pot institutional stoves and their uptake is limited by coordination among stakeholders. The case study in South Africa stresses that designs must be manufacturable. The case study at Aprovecho shows how advanced measurements and data analytics led to new design insights. Attendees of this talk will learn how the lab can be a springboard for designs which can be implemented if its activities are informed by field data, and will learn about the tools used for lab and field measurements.

High quality and reliable cookstove testing provide a critical foundation to advancing clean cooking solutions worldwide. Regional Testing and Knowledge Centers (RTKCs) play a pivotal role in our sector, providing essential testing services so manufacturers can quantify emission and efficiency advances. However, a recent needs assessment conducted by the Clean Cooking Alliance (CCA) revealed that RTKCs face challenges related to business operations and sustaining capacity within the laboratories.


This presentation will share key findings from the needs assessment, including specific gaps identified in RTKC capacity and the implications for the clean cooking sector. Additionally, we will discuss an innovative solution being co-developed by CCA and partners: a comprehensive interactive online training course designed to equip laboratory staff with step-by-step guidance on how to complete the ISO laboratory testing procedures and build related skills.


Attendees will gain insights into the critical role of RTKCs, the challenges they face, and how tailored capacity-building initiatives can drive impact in the clean energy sector. The goal of this presentation is to illicit feedback and drive further stakeholder engagement.

We study a $40 energy efficient charcoal cookstove in an experiment with 1,000 households in Nairobi. We estimate a 39% reduction in charcoal usage which corresponds to 331 kilograms charcoal, saving adopters $119 per year. Our methodology is stacking-agnostic. We collect high-frequency data on individual pollution exposure using Purple Air monitors kept in backpacks. The stoves reduce PM2.5 spikes while cooking by 52µg/m3 (42%) and cause a 0.24SD reduction in self-reported respiratory symptoms. However, even after more than three years of daily usage, we find no clinical health improvements, possibly because we detect no impact on average exposure. Using the methodology from Gill-Wiehl et al (2024) and a 45% fNRB (UNFCCC, 2023) we calculate a reduction of 1.81 tCO2 per stove-year. Factoring in the additionality and breakage rates that we observe over 3.5 years this results in an abatement cost of $10.69 per tCO2 avoided.

My 10-minute presentation will discuss the environmental and cardiovascular impacts of China’s Rural Clean Heating Policy (CHP), which was implemented village-by-village in northern China beginning in 2016. The CHP aimed to transition homes from coal stoves to electric heat pumps for space heating by banning household coal burning, expanding the electricity grid, and offering subsidies for electric heaters and nighttime electricity. Using field-collected data from a four-year longitudinal study in rural Beijing with measurements in over 1,400 households in 50 villages, my presentation will show that policy implementation increased indoor temperature, particularly the minimum daily temperature, improved indoor air quality, and modestly lowered adult blood pressure. Using new statistical mediation methods, I will also show that the observed reductions in blood pressure are largely because the policy reduced indoor PM2.5 and improved indoor temperature. Households continued to use biomass throughout the study period, which was not targeted by the policy, and I will discuss that the mixed use of fuels may have attenuated the potential benefits of the policy on blood pressure. The audience will learn about an exciting new policy that by 2021 had transitioned ~36 million households to electric heating, our four-year impact evaluation of the CHP, and the potential downstream indoor environment and health benefits of switching from solid to cleaner fuels for space heating.

Smallholders in Southern Africa are now making biochar from crop residues in simple retorts to improve soil and animal health. The use of maize stalks, straws, and other agricultural residues offsets the use of wood. Retorts range from simple pit kilns to metal TLUDs which can be adopted by cookstove projects. Techniques are disseminated in village-scale workshops conducted between growing seasons. Some entrepreneurs make biochar-based fertilizers for sale. Other producers make cooking fuels from crop residues. Learn how smallholders sell carbon dioxide removal credits for the biochar they make through a special artisanal carbon sink protocol. The carbon credits are sold on the international market. Examples will be described like the Warm Heart Worldwide/Biochar.Life projects in Malawi, Kenya, the Democratic Republic of Congo, and Tanzania, in biochar-making stove projects in Ghana and Burundi, and through the Circular Bionutrient Economy Network (CBEN) in Nairobi. Testimonials will be presented to show how biochar and carbon markets have increased income and food security.

A review of recent trends and market drivers for carbon credits from clean cooking projects, since ETHOS 2024