Laboratory based assessment of cookstove performance using energy and emission parameters for North Indian cooking cycle

The study was conducted to evaluate the performance of cookstoves using controlled cooking test (CCT) with cooking cycles of Northern India, i.e., Uttar Pradesh (UP) and Uttarakhand (UK). Cooking time, specific energy consumption (SEC), and emission factors (EFs) of carbon monoxide (CO) and particulate matter (PM) were monitored for three improved and one traditional cookstoves. Cooking was conducted by residents of the study area. The findings from the study showed that the difference in thickness of roti baked in UP and UK resulted in a significant change in emission and energy performance in all the four cookstoves. The low-power inputs required for baking thinner roti resulted in higher CO and PM emissions in case of CCT-UK. The results of CCT were also compared to Water Boiling Test (WBT) for all the four cookstoves. The percent reductions in terms of energy and emission parameters in the three improved cookstoves compared to traditional cookstove were found to differ in CCT and WBT. Large variations were also observed during the emission performance (40% decrease in CO EF) of the fan cookstove with change in fan speed, which was usually unreported in previous studies. Overall, results show significant influence of cooking cycles on cookstove performance, which was found to alter the cookstove rankings. Therefore, the study thrusts upon the inclusion of user centric cookstove testing protocols in order to identify actual benefits for targeted rural communities.     

Financial analysis of cooking energy options for India

A financial analysis of cooking energy options is attempted for India using data from a field study and real costs and prices. The fuels considered are; fuelwood, kerosene, biogas, liquid petroleum gas (LPG) and electricity. Traditional and efficient devices and different discount rates are used in the analysis. Financial analysis for rural areas shows that the efficient Astra-stove using wood is the least cost option and biogas, which is the only quality fuel option for rural areas, is the most expensive option. The subsidised kerosene option is cheaper than wood in the traditional stove. The ranking of options from low to high costs is from fuelwood to kerosene to LPG to biogas. In the urban situation, the subsidy on kerosene distorts the energy ladder. Kerosene is the low cost fuel option, and fuelwood in the traditional stove is among the most expensive options. The existing subsidies on kerosene, LPG and electricity seem to benefit middle and high income groups, particularly in urban areas. Low income households in urban and rural areas are forced to use fuelwood in traditional stoves, which is not only a low quality fuel but is also a high cost cooking energy option. The efficiency of the device is shown to be a crucial factor in determining the cost of using a fuel. Low income households are disadvantaged, as they use traditional low efficiency wood stoves. A need to alter energy policies to promote quality fuels and efficient devices in an accessible way to low income households is highlighted.     

Fuel use and design analysis of improved woodburning cookstoves in the Guatemalan Highlands

This study examined the fuel use and design of an improved woodburning cookstove (plancha), in comparison to traditional cooking over an open woodfire. These cookstoves had been randomly introduced into population households in the Guatemalan Highlands that had previously used open woodfires. This research consisted of: (1) a 12-household Kitchen Performance Test (KPT) over a 4-day period and (2) single-day participant observation in five households. The KPT monitored fuel consumption and the number, age, and gender of people who were cooked for, while the participant observation was used to form a complete understanding of fuel use patterns and to examine the influence of stove condition and cooking behavior. In spite of fairly low variability in the fuel use data (coefficients of variation of about 0.34) the KPT did not show statistically significant differences in fuel use between the two cooking methods. It is possible that increased study power through a larger sample size may have resulted in a statistically significant difference in favor of the plancha, but it is doubtful that the size of the effect would be of any practical significance. Thus, although other studies have shown that the plancha is extremely effective in reducing indoor air pollution in the study area, the KPT did not indicate that it offered any benefits with respect to fuel use. Practical and experimental recommendations for future cookstove efficiency studies are presented, with directions for continued work in this area.     

Performance of large portable metal woodstoves for community kitchens

Experiments were undertaken in the laboratory to test the performance of traditional three-stone open fire cooking against a large-sheet metal fuelwood cookstove designed for community kitchens. The standard water boiling test was performed for both cooking methods. The percent heat utilisation, firepower and the specific fuel consumption are calculated. Results show the cookstove to be at least three times as fuel efficient as the open fire. Also it consumed about one fifth of the energy of the open fire method in boiling an equivalent amount of water. Preliminary feedback from actual use in the field corroborates these experimental findings. Appreciable savings in wood consumption, fuelwood collection time, and fuelwood purchase costs are noted. Tangible health and social benefits from using the cookstoves are enumerated. Suggestions for simplifying the stove fabrication process, improving field dissemination and creating a possible cottage industry are proposed.     

Energy consumption in three rural Kenyan households: A survey

Woodfuel is an important source of fuel energy in Kenya, constituting about 75% of the total energy consumed. The rural population relies almost entirely on fuelwood which has become increasingly difficult to obtain. In this study a questionnaire was used to establish the form and quantity of fuel used and the types of stoves used in rural households within Nyeri, Wanguru in Embu and Muhoroni in Kisumu. Forty households in Nyeri and 30 in each of the other two areas were randomly selected for the study. The availability of agricultural residues for use as fuel and the possibility of using briquettes for cooking were established. It was found that all the households have a 3-stone cooking stove in which they burn fuelwood or agricultural residues. Cowdung is used in Embu but not in Nyeri and Kisumu. The degree to which the population relies on agricultural residues for fuel varies among the villages. In Nyeri, most of the agricultural residues are either fed to cattle or left in the field. In Embu only a few of the houses use maize cobs and stalks. However, the rural population in Muhoroni rely heavily on sugarcane residues for their cooking fuel. In general, 15–35% of a household's income is spent on fuel though this does not take into account the time spent gathering fuel.     

Evaluation of the performance of improved biomass cooking stoves with different solid biomass fuel types

We have studied the performance of different types of improved solid biomass cookstoves (Two natural draft and one forced draft) in comparison to the traditional cookstove (control) while preparing a particular meal with a variety of solid biomass fuels (e.g. fuel wood, dung cake and crop residue). Five replicates of each type of cookstove and fuel were maintained. The study was conducted in an Indian rural kitchen. There was no significant difference in the indoor concentrations of PM_2.5 and CO when natural draft and traditional cookstoves were used with any type of solid fuel. However, significantly lower concentrations of PM_2.5 and CO were recorded with forced draft stoves compared to others. While cooking with different types of solid biomass fuels, the concentrations of PM_2.5 and CO in the indoor environment were decreased by 21–57% and 30–74% respectively with the forced draft cookstove in comparison to the traditional cookstove. The fuel consumption, cooking duration and thermal efficiency of a particular stove to prepare a particular amount of food also differ depending on the type of the solid fuel used for the cooking purpose. The thermal efficiency of traditional, natural draft and FD cookstoves were in the range of 15–17%, 16–27% and 30–35% respectively for different types of solid biomass fuels. However, further studies on the performance of stoves are required based on the size and type of fuel wood or crop residues.     

Wood fuel use in the traditional cooking stoves in the rural floodplain areas of Bangladesh: A socio-environmental perspective

A study was conducted, using a multistage simple random sampling design, to determine the structural characteristics of the traditional cooking stoves, amount of wood fuel consumed in the rural floodplain areas in Bangladesh, and also to figure out the socio-economic and environmental consequences of wood fuel usage in the traditional cooking stove. The study showed that family size, income, amount cooked and burning hours significantly affected the amount of wood fuel used per family per year. Taking into account different family sizes, the study observed that 4.24 tonne fuelwood were consumed per family per year. The study showed that 42% of families used only biomass fuel, 5% used liquefied petroleum gas (LPG) and 53% used kerosene along with biomass fuels. The main source of biomass fuel was homestead forests (40%). It has been figured out that the incomplete combustion of biomass in the traditional cooking stove poses severe epidemiological consequences to human health and contributes to global warming. The study also showed that 83% of the respondents would prefer improved cooking stoves over traditional cooking stoves.     

Stoves or sugar? Willingness to adopt improved cookstoves in Malawi

Malawi has set a target of adoption of two million improved cookstoves (ICS) by 2020. Meeting this objective requires knowledge about determinants of adoption, particularly in rural areas where the cost of traditional cooking technologies and fuels are non-monetary, and where people have limited capacity to purchase an ICS. We conducted a discrete choice experiment with 383 households in rural Malawi asking them if they would chose a locally made ICS or a package of sugar and salt of roughly equal value. Six months later, we assessed adoption and stove use patterns. Sixty-six percent of households chose the ICS. We find that having a larger share of crop residues in household fuel supply, awareness of the environmental impacts of woodfuel reliance, time the primary cook devotes to collecting fuelwood, and peer effects at the village-level increase the odds of choosing the ICS. Having a large labor supply for fuelwood collection and experience with a non-traditional cooking technology decreased the odds of choosing the ICS. In a rapid assessment six months after stoves were distributed, we found 80% of households were still using the ICS, but not exclusively. Our findings suggest considerable potential for wide-scale adoption of low cost ICS in Malawi.     

Solid-fuel household cook stoves: Characterization of performance and emissions

In this study, 14 solid-fuel household cook stove and fuel combinations, including 10 stoves and four fuels, were tested for performance and pollutant emissions using a WBT (Water Boiling Test) protocol. Results from the testing showed that some stoves currently used in the field have improved fuel efficiency and lower pollutant emissions compared with traditional cooking methods. Stoves with smaller-mass components exposed to the heat of fuel combustion tended to take lesser time to boil, have better fuel efficiency, and lower pollutant emissions. The challenge is to design stoves with smaller-mass components that also have acceptable durability, affordable cost, and meet user needs. Results from this study provide stove performance and emissions information to practitioners disseminating stove technology in the field. This information may be useful for improving the design of existing stoves and for developing new stove designs. Comparison of results between laboratories shows that results can be replicated between labs when the same stove and fuel are tested using the WBT protocol. Recommendations were provided to improve the ability to replicate results between labs. Implications of better solid-fuel cook stoves are improved human health, reduced fuel use, reduced deforestation, and reduced global climate change.     

Wood cookstoves in Fiji

In almost all rural areas of the Pacific Island Nations cooking is predominantly accomplished using wood fires. Many attempts have been made by aid agencies and benevolent organizations to introduce improved woodstoves. The main reasons were to conserve wood fuel and to provide a healthier environment in the kitchen area. The present paper details a study of eight rural villages in Fiji to investigate cooking habits and wood stove cooking experience. The results suggest that in actual practice stoves are not more efficient than open fires and that the management of the fireplace is the key to overall fuel efficiency. More emphasis should be placed on providing more accessible fuel by concentrating on fuelwood lots close to the villages and to looking at the kitchen environment as an integrated whole and not just focussing on the cooking stove.     

The economics of improved charcoal stoves in Kenya

Charcoal for cooking is a major expenditure for urban households in Kenya and improved stoves can reduce fuel costs by at least 25%. The author relates how, although an improved stove is more expensive than a traditional stove, the payback period is short and an improved stove also lasts longer. The benefits to society of a programme to encourage small-scale, informal sector production of charcoal stoves are seen to be large, even after accounting for the administrative costs. Such a programme may also provide limited employment and income gains for producers. The environmental impacts may be significant because of the energy loss in converting wood to charcoal and the fact that charcoal is usually made from felling whole trees.     

Induction stoves as an option for clean cooking in rural India

As part of a programme on ‘access to clean cooking alternatives in rural India’, induction stoves were introduced in nearly 4000 rural households in Himachal Pradesh, one of the few highly electrified states in India. Analysis of primary usage information from 1000 rural households revealed that electricity majorly replaced Liquid Petroleum Gas (LPG), generally used as a secondary cooking fuel, but did not influence a similar shift from traditional mud stoves as the primary cooking technology. Likewise, the shift from firewood to electricity as a primary cooking fuel was observed in only 5% of the households studied. Country level analysis indicates that rural households falling in lower monthly per capita expenditure (MPCE) classes have lesser access to electricity and clean cooking options than those falling in higher MPCE classes. Again, only three states in India with high levels of rural household electrification report consumption statuses more than 82 kWh per month (the estimated mean for electricity consumption by induction stoves). Overall, the results of the study indicate that induction stoves will have limited potential in reducing the consumption of firewood and LPG if included in energy access programmes, that too only in regions where high levels of electrification exist.     

What makes people adopt improved cookstoves? Empirical evidence from rural northwest Pakistan

Large dependence of the world population on biomass fuels for domestic energy consumption is one of the major anthropogenic causes of deforestation worldwide. The use of biomass in inefficient ways in rural areas increases fuelwood demand of a household. Development of the improved biomass stove programs in the 1970s has been one of the efforts to reduce burden on biomass resource base through reliable and efficient methods of energy consumption. However, despite having multiple economic, social, environmental, and health benefits; the improved stove dissemination programs failed to capture worldwide recognition. A wide array of socio-cultural, economic, political, and institutional barriers contributes to the low adoption rate of such programs. Drawing on field work surveys in rural northwest Pakistan, this paper provides empirical evidence of individual, household, and community level variables that play a vital role in the adoption of improved cookstoves. The study is based on primary data collected from 100 randomly selected households in two villages of rural northwest Pakistan. Using regression analysis, the study depicts that education and household income are the most significant factors that determine a household willingness to adopt improved biomass stoves. The study concludes that the rate of adoption could substantially be improved if the government and non-governmental organizations (NGOs) play a greater role in overcoming the social, economic, cultural, political, and institutional barriers to adopting improved cooking technologies.     

Biomass availability, energy consumption and biochar production in rural households of Western Kenya

Pyrolytic cook stoves in smallholder farms may require different biomass supply than traditional bioenergy approaches. Therefore, we carried out an on-farm assessment of the energy consumption for food preparation, the biomass availability relevant to conventional and pyrolytic cook stoves, and the potential biochar generation in rural households of western Kenya. Biomass availability for pyrolysis varied widely from 0.7 to 12.4 Mg ha⁻¹ y⁻¹ with an average of 4.3 Mg ha⁻¹ y⁻¹, across all 50 studied farms. Farms with high soil fertility that were recently converted to agriculture from forest had the highest variability (CV = 83%), which was a result of the wide range of farm sizes and feedstock types in the farms. Biomass variability was two times lower for farms with low than high soil fertility (CV = 37%). The reduction in variability is a direct consequence of the soil quality, coupled with farm size and feedstock type. The total wood energy available in the farms (5.3 GJ capita⁻¹ y⁻¹) was not sufficient to meet the current cooking energy needs using conventional combustion stoves, but may be sufficient for improved combustion stoves depending on their energy efficiency. However, the biomass that is usable in pyrolytic cook stoves including crop residues, shrub and tree litter can provide 17.2 GJ capita⁻¹ y⁻¹ of energy for cooking, which is well above the current average cooking energy consumption of 10.5 GJ capita⁻¹ y⁻¹. The introduction of a first-generation pyrolytic cook stove reduced wood energy consumption by 27% while producing an average of 0.46 Mg ha⁻¹ y⁻¹ of biochar.     

Reducing health impacts of biomass burning for cooking—the need for cookstove performance testing

Biomass is a renewable energy source that is routinely used for cooking in the developing world, especially in rural areas. The World Health Organization estimates that about 2.5 billion people globally rely on biomass, such as wood, agricultural waste and animal dung to meet their energy needs for cooking utilising traditional low-efficiency cookstoves. However, certain human health risks are associated with the inhalation of off-gases resulting from the indoor use of biomass for cooking, especially for women and children who spend more of their time at home. On the other hand, use of energy-efficient cookstoves is considered to reduce those risks. Thus, qualitative and quantitative measurements of cookstove performance are necessary in order to make different stoves and different cooking processes comparable. The aim of this paper is the presentation of the current situation regarding biomass use for cooking with emphasis placed on the developing world, the brief of the adverse health impacts of biomass burning based on the review of literature, the presentation of the merits of improved efficiency cookstoves and to highlight the need for stove performance tests. The demand of different types of biomass is not likely to change in the near future in the developing world since biomass is readily available and cheap. Thus, the efforts to improve household air quality must concentrate on improving cookstoves efficiency and ventilation of the flue gases outdoors. Programmes for the improvement of the cookstoves efficiency in the developing world should be part of the development agenda.     

The development impact of solar cookers: A review of solar cooking impact research in South Africa

Solar cooking is often considered “a solution looking for a problem”. Solar cookers have long been presented as an interesting solution to the world's problem of dwindling fuel wood sources and other environmental problems associated with wood fuel demand for cooking. However, recent GTZ field work in South Africa showed different benefits instead: the use of solar cookers resulted in appreciable fuel and time savings as well as increased energy security for households using commercial fuels. These observations are based on field tests in South Africa that started in 1996 to investigate the social acceptability of solar cookers and to facilitate local production and commercialisation of the technology. Impact studies and use rate studies have been carried out by a number of different organisations since the inception of the project and although commercialisation of the technology has not been achieved to its fullest potential, impact studies indicate that solar cookers have a positive development impact on households through fuel-, energy- and time savings. The article aims to summarise the findings of the various studies and present an overview of use rates and impact data. A variety of factors influence solar cooker use rates, which in turn determine impacts. Some factors are related to the user, some to the environment in which the cooker is used and some to the cooker itself. Ultimately, the data shows that on average, only 17% of solar cooker owners do not use their stoves after purchase and that active solar cooker users utilise their stoves on average for 31% of their cooking incidences. Since the majority of solar stove buyers actually use their stoves and obtain real benefits, this suggests that that solar cookers are indeed not a solution looking for a problem but a solution worth promoting.     

Hybrid application of biogas and solar resources to fulfill household energy needs: A potentially viable option in rural areas of developing countries

The absence of clean cooking facilities and electricity means billions of rural people are deprived of much needed socioeconomic development. Livestock residues (dung) and solar radiation are two renewable energy resources that are abundantly available in rural areas of developing countries. Although it is not feasible for these two resources separately to meet both thermal (cooking) and electricity demands, hybrid applications have not been given due attention. To facilitate integrating these two resources in rural energy planning, and to promote their dissemination through hybrid applications, it is necessary to evaluate their economic merits, and assess their ability to deal with the demands. In this paper, we examine the techno-economic performance of hybrid applications of these two resources by applying a simulation technique using the HOMER tool, and by giving derived cost-saving equations. We also quantify the monetary savings from replacing traditional fuels, and perform a sensitivity analysis on a number of variables (e.g. dung cost, fuelwood cost) to see how they affect the performance of different energy supply alternatives. Furthermore, we examine the practical applicability of the biogas system in the households through a structured survey of 72 ongoing household biogas plants. This study finds that households that have between three and six cattle can potentially meet their cooking and electricity loads through a hybrid implementation of biogas and solar PV (Photovoltaic) system. By replacing conventional fuels households can achieve savings that are more than the total annualized costs incurred for installing new services.     

Improved stoves in India: A study of sustainable business models

Burning of biomass for cooking is associated with health problems and climate change impacts. Many previous efforts to disseminate improved stoves – primarily by governments and NGOs – have not been successful. Based on interviews with 12 organizations selling improved biomass stoves, we assess the results to date and future prospects of commercial stove operations in India. Specifically, we consider how the ability of these businesses to achieve scale and become self-sustaining has been influenced by six elements of their respective business models: design, customers targeted, financing, marketing, channel strategy, and organizational characteristics. The two companies with the most stoves in the field shared in common generous enterprise financing, a sophisticated approach to developing a sales channel, and many person-years of management experience in marketing and operations. And yet the financial sustainability of improved stove sales to households remains far from assured. The only company in our sample with demonstrated profitability is a family-owned business selling to commercial rather than household customers. The stove sales leader is itself now turning to the commercial segment to maintain flagging cash flow, casting doubt on the likelihood of large positive impacts on health from sales to households in the near term.     

Rural household livelihood change,fuelwood substitution,and hilly ecosystem restoration: Evidence from China

This paper systematically analyzes the driving forces and mechanism of fuelwood substitution and related ecological consequences in an under-developed county in rural Southeast China. Based on 358 respondents from rural households in Changting County, as well as additional statistical data, we present strong evidence in support of the argument that changes in the livelihoods of rural households lead to fuelwood substitution and finally, hilly ecosystem restoration. Important factors influencing fuelwood substitution are closely linked with changes in rural livelihoods: off-farm employment and agricultural specialization. Therefore, these changes are argued to be the primary driving force of fuelwood substitution. Reasons include the increasing opportunity costs of fuelwood collection, increases in household income, and decreases in household energy consumption for cooking, feeding and heating. Such changes have unexpectedly caused significant progress in hilly ecosystem restoration, particularly in mitigation of soil erosion and forest degradation. Thus, it is suggested that the progressive change and improvement in the livelihoods of rural households should be included in the mix of policies intended to restore hilly ecosystems.     

Preferences for improved cook stoves: Evidence from rural villages in north India

Because emissions from solid fuel burning in traditional stoves impact global climate change, the regional environment, and household health, there is today real interest in improved cook stoves (ICS). Nonetheless, surprisingly little is known about what households like about these energy products. We report on preferences for biomass-burning ICS attributes in a large sample of 2120 rural households in north India, a global hotspot for biomass fuel use and the damages that such use entails. Households have a strong baseline reliance and preference for traditional stoves, a preference that outweighs the $10 and $5 willingness to pay (WTP) for realistic (33%) reductions in smoke emissions and fuel needs on average, respectively. Preferences for stove attributes are also highly varied, and correlated with a number of household characteristics (e.g. expenditures, gender of household head, patience and risk preferences). These results suggest that households exhibit cautious interest in some aspects of ICS, but that widespread adoption is unlikely because many households appear to prefer traditional stoves over ICS with similar characteristics. The policy community must therefore support a reinvigorated supply chain with complementary infrastructure investments, foster experimentation with products, encourage continued applied research and knowledge generation, and provide appropriate incentives to consumers, if ICS distribution is to be scaled up.