Abhishek Kar

Real-time assessment of black carbon pollution in Indian households due to traditional and improved biomass cookstoves.

Use of improved (biomass) cookstoves (ICs) has been widely proposed as a Black Carbon (BC) mitigation measure with significant climate and health benefits. ICs encompass a range of technologies, including natural draft (ND) stoves, which feature structural modifications to enhance air flow, and forced draft (FD) stoves, which additionally employ an external fan to force air into the combustion chamber. We present here, under Project Surya, the first real-time in situ Black Carbon (BC) concentration measurements from five commercial ICs and a traditional (mud) cookstove for comparison. These experiments reveal four significant findings about the tested stoves. First, FD stoves emerge as the superior IC technology, reducing plume zone BC concentration by a factor of 4 (compared to 1.5 for ND). Indoor cooking-time BC concentrations, which varied from 50 to 1000 μg m(-3) for the traditional mud cookstove, were reduced to 5-100 μg m(-3) by the top-performing FD stove. Second, BC reductions from IC models in the same technology category vary significantly: for example, some ND models occasionally emit more BC than a traditional cookstove. Within the ND class, only microgasification stoves were effective in reducing BC. Third, BC concentration varies significantly for repeated cooking cycles with same stove (standard deviation up to 50% of mean concentration) even in a standardized setup, highlighting inherent uncertainties in cookstove performance. Fourth, use of mixed fuel (reflective of local practices) increases plume zone BC concentration (compared to hardwood) by a factor of 2 to 3 across ICs.

How do People in Rural India Perceive Improved Stoves and Clean Fuel? Evidence from Uttar Pradesh and Uttarakhand

Improved cook stoves (ICS) have been widely touted for their potential to deliver the triple benefits of improved household health and time savings, reduced deforestation and local environmental degradation, and reduced emissions of black carbon, a significant short-term contributor to global climate change. Yet diffusion of ICS technologies among potential users in many low-income settings, including India, remains slow, despite decades of promotion. This paper explores the variation in perceptions of and preferences for ICS in Uttar Pradesh and Uttarakhand, as revealed through a series of semi-structured focus groups and interviews from 11 rural villages or hamlets. We find cautious interest in new ICS technologies, and observe that preferences for ICS are positively related to perceptions of health and time savings. Other respondent and community characteristics, e.g., gender, education, prior experience with clean stoves and institutions promoting similar technologies, and social norms as perceived through the actions of neighbours, also appear important. Though they cannot be considered representative, our results suggest that efforts to increase adoption and use of ICS in rural India will likely require a combination of supply-chain improvements and carefully designed social marketing and promotion campaigns, and possibly incentives, to reduce the up-front cost of stoves.

Reductions in indoor black carbon concentrations from improved biomass stoves in rural India.

Deployment of improved biomass burning cookstoves is recognized as a black carbon (BC) mitigation measure that has the potential to achieve health benefits and climate cobenefits. Yet, few field based studies document BC concentration reductions (and resulting human exposure) resulting from improved stove usage. In this paper, data are presented from 277 real-world cooking sessions collected during two field studies to document the impacts on indoor BC concentrations inside village kitchens as a result of switching from traditional stoves to improved forced draft (FD) stoves. Data collection utilized new low-cost cellphone methods to monitor BC, cooking duration, and fuel consumption. A cross sectional study recorded a reduction of 36% in BC during cooking sessions. An independent paired sample study demonstrated a statistically significant reduction of 40% in 24 h BC concentrations when traditional stoves were replaced with FD stoves. Reductions observed in these field studies differ from emission factor reductions (up to 99%) observed under controlled conditions in laboratory studies. Other nonstove sources (e.g., kerosene lamps, ambient concentrations) likely offset the reductions. Health exposure studies should utilize reductions determined by field measurements inside village kitchens, in conjunction with laboratory data, to assess the health impacts of new cooking technologies.