Traditional cookstoves, prevalent in rural communities, exhibit a multifaceted array of deleterious impacts. Notably, they contribute significantly to carbon emissions, black carbon (soot), and various volatile organic compounds. These emissions are major contributors to indoor air pollution, leading to adverse health effects. In India, the World Energy Outlook reports that, approximately 840 million people rely on traditional biomass cookstoves for their cooking needs. 

Based on surveys conducted by TIDE and supported by secondary research, it was inferred that the transition to LPG for rural households remains a distant prospect due to affordability and logistical challenges, particularly in forest and forest fringe areas. Moreover, social culinary preferences, such as the preparation of ragi balls, and cultural habits related to taste are difficult to replicate on an LPG stove. Traditional cookstoves, prevalent in rural and forest fringe regions, burn excessive amounts of solid fuels like wood, coal, or biomass, exacerbating deforestation. The level of CO2 emissions from these traditional biomass-based cookstoves varies based on factors such as fuel type, stove design, combustion efficiency, and cooking practices, but they consistently contribute to significant greenhouse gas emissions. On average, traditional biomass cookstoves emit between 2 to 5 metric tons of CO2 equivalent per household per year.  

 The release of CO2 and other harmful gases during combustion contributes to the concentration of greenhouse gases in the atmosphere, thereby exacerbating global warming and climate disruption, which disproportionately affect vulnerable communities. The utilisation of traditional cookstoves leads to indoor air pollution due to the incomplete combustion of solid fuels, exposing households, especially women and children, to harmful particulate matter and pollutants. According to the World Health Organization (WHO), indoor air pollution is responsible for approximately 3.2 million deaths worldwide. In India, indoor air pollution is responsible for approximately 1.3 million deaths annually.  

Furthermore, women in India play a significant role and occupy a central position in domestic culinary affairs, assuming primary responsibility for culinary tasks within households. This demographic predominance exposes them to increased susceptibility to indoor air pollution within the household originating from inefficient combustion of solid biomass fuels. Moreover, women spend more than two weeks annually gathering traditional biomass fuels, a labour-intensive activity that heightens their exposure to potential risks, including encounters with wildlife. 

Based on the above-mentioned context, the following are the specific challenges that this project aims to address: 

1. Indoor Air Pollution and Health Impacts: In rural areas, the prevalent use of traditional firewood cookstoves without adequate chimneys results in elevated levels of indoor air pollution. Data from TIDE’s survey indicate that the average PM2.5 concentration in kitchen indoor spaces is 47 µg/m³, exceeding the WHO standard limit for the 24-hour mean PM2.5 value indoors. Furthermore, the average carbon monoxide (CO) concentration of 5.16 mg/m³ surpasses the permissible 1-hour CO value of 4 mg/m³ as established by the National Ambient Air Quality Standards (NAAQS) in 2009. This situation poses a significant health risk, especially for women, who are exposed to harmful pollutants during daily cooking activities.
2. Environmental Degradation and Inefficient Biomass Usage: The conventional culinary methodologies observed within the communities are implicated in environmental degradation due to the inefficient utilisation of biomass. Based on TIDE’s survey data from selected districts in Karnataka, traditional biomass cookstoves, on average, consume approximately 11 kilograms of biomass per day for cooking purposes. The depletion of indigenous wood resources not only imperils the local ecosystem but also intensifies apprehensions regarding climate change. Immediate action is imperative to combat these environmental challenges and facilitate the community’s shift toward sustainable cooking practices, thereby ensuring enduring environmental resilience and well-being.
3. Socio-Economic Burden of Traditional Cooking Practices: The widespread use of inefficient traditional cookstoves in rural communities imposes substantial socio-economic burdens, particularly on women responsible for gathering firewood. This project aims to address these challenges through the implementation of improved cookstoves, thereby mitigating associated risks, reducing the labourious task of wood collection, and providing rural communities, particularly women, with opportunities for supplementary income through the manufacturing of sustainable improved cookstoves. 

To address these intertwined social and climate challenges and concerns, the adoption of sustainable and community centric solutions becomes imperative. One promising approach is the implementation of improved cookstoves, exemplified by the Sarala cookstoves.  

Derived from a design initially developed at the Indian Institute of Science (IISc), Bangalore, and further adapted by TIDE, Sarala (‘Simple’ in English) stands out due to its alignment with community’s cultural norms and intuitive usability akin to conventional stoves. Engineered to mitigate carbon emissions, enhance energy efficiency, and combat indoor air pollution, Sarala cookstoves feature a dual-pan mud stove design with a chimney, utilising locally sourced firewood and agricultural residue for cooking. 

Installation and construction of Sarala cookstoves are carried out by trained personnel from TIDE on-site, ensuring effective deployment and usability. Continuous research and development efforts have led to significant improvements in combustion chamber size, airflow optimisation, and overall performance metrics. These advancements enable maximum fuel utilisation, improved heat transfer efficiency, and minimised heat loss during cooking, culminating in notable reductions of 75-80% in CO2 emissions and 85-90% in PM2.5 levels within household environments. The thermal efficiency of Sarala stoves now achieves an impressive 27-30%.

Key features of the Sarala cookstoves include- 

1.  On-site construction of a dual-pan stove 
2.  Simultaneous cooking in two pans, optimising time 
3.  Natural draft chimney expels smoke from the kitchen 
4.  Versatile, accepts all kinds of biomass fuels 
5.  Reduced soot deposition on cooking vessels 
6.  Quick usability within 4-5 days of on-site assembly 
7.  Local repair and maintenance options 
8.  Estimated more than 7-year lifespan with proper O&M 
9.  Compact footprint: 2.5 ft x 1.5 ft 
10.  Energy-efficient combustion chamber, burning 850gm-1 kg of fuel per hour
     

In 2023, TIDE installed over 800 Sarala cookstoves in identified villages of Kodagu and Chikballapura districts of Karnataka. With a longstanding presence spanning three decades, TIDE has successfully distributed over 50,000 stoves across various states in India, thereby enhancing the livelihoods of over 300,000 rural and tribal inhabitants. The Sarala cookstove, characterised by its in-situ design, achieves a utilisation rate of 100%, with some beneficiaries using the cookstoves for more than 15 years.