A localized solution for reducing black carbon emission from fuelwood is using improved cookstoves, which are safe and increase efficiency
Energy is vital for economic and social development. In most developing countries, wood and other biomass fuels are still the primary source of energy for the majority of people, especially the poor. Nepal is no different: 87 percent of the nation’s energy is supplied from traditional biomass, and 75 percent of Nepali households still depend on biomass as a cooking fuel. Unfortunately, many of these cookstoves also create serious health problems for their users. Data from the World Health Organization states that harmful smoke from cookstoves burning solid fuels is the fifth worst overall health risk in developing countries. This is partly because of the high concentration of black carbon—a by-product of incomplete combustion—that is found in the smoke billowing out of most cookstoves, especially in rural Nepal and other developing regions.
The smoke from cookstoves, which also contains minute and health-threatening particulate matter, contributes to a range of chronic illnesses and acute health impacts such as pneumonia, lung cancer, bronchitis, cardiovascular disease, and low birth weight. In addition, women and girls forced to collect fuelwood far from the safety of their homes are at high risk of gender violence and physical injury. The time required to collect fuelwood—most often a task assigned to women and girls—often results in losses in economic productivity and missed educational opportunities. Children are also at risk of painful and debilitating injury from burning fires left unattended in traditional cookstoves.
Surprising to some people, the black carbon in the exhaust spewing from household cookstoves also has significant near-term impacts on the climate, especially in mountain areas. It is estimated that cookstoves account for approximately 20 percent of global black carbon emissions and a significant share of ambient air pollution in the developing world.
Black carbon can affect the climate in two ways. When suspended in air, black carbon absorbs sunlight and generates heat in the atmosphere, warming the air and depriving the surface underneath of sunlight. This can result in cooling of valleys and lowland areas, contributing to the increased build-up of fog and lowering of winter temperatures in river valleys and over the northern Ganges Plains. It can also affect regional cloud formation and precipitation patterns. When black carbon is deposited on snow and ice, its dark particles absorb sunlight. The heat generated as a result warms both the air above and the snow and ice below, accelerating melting.
Photo: Nabin Bara
Because black carbon is short-lived (remaining in the atmosphere for only one to four weeks), its climate effects are largely regional. Its short lifetime also means that negative effects would dissipate quickly if black carbon emissions were reduced, directly benefiting the countries or communities that invest in policies to reduce black carbon emissions.
One localized solution for reducing black carbon is the use of improved cookstoves, which increase the efficiency of use of biofuels (even cutting the needed amount of fuelwood in half), reduce total emissions, and are safe to use. Nepal has a long history with improved cookstoves, dating back to their introduction in 1950. However, it wasn’t until after 1990, with the development of the mud brick stove by the Research Center for Applied Science and Technology-Nepal(RECAST), that the dissemination and use of improved cookstoves gained some momentum. In 1999, a national program for improved cookstoves was initiated with support from the Energy Sector Assistance Program of DANIDA and the Alternative Energy Promotion Center, an initiative of the Government of Nepal. With the launch of the six-year National Rural and Renewable Energy Program in 2012, the use of improved cookstoves is expanding, with over 621,826 improved cookstoves installed in Nepal since the first was introduced 60 years ago.
Keeping in mind this relatively attainable and applicable solution, the International Centre for Integrated Mountain Development (ICIMOD) is conducting a study on Reducing the Impacts of Black Carbon and other Short-Lived Climate Pollutants with support from the Swedish International Development Cooperation Agency (SIDA). As a part of the project, researchers are exploring ways to effectively reduce black carbon emissions from sources such as household cookstoves, which could also improve people’s health. However, not all improved cookstoves are created equal: there is significant variability among different cookstoves and fuel combinations in the emission of particulate matter and black carbon. Although rare, some have been shown to reduce the overall emission of particulate matter, while the fraction of black carbon actually increases. An intelligent strategy for disseminating improved cookstoves that meet all the necessary criteria could garner joint benefits for the climate and the health of rural communities, while also ensuring efficiency and economy of use.
The timely, yet ambitious, goal made by the prime minister for clean cooking energy solutions for all by 2017 could transform the way millions of Nepalis cook. This is a positive step towards mitigating the effects of black carbon, not only in the kitchen, but also on the climate of the region. This initiative could further open doors to the private sector for engagement in the areas of offsetting black carbon, carbon credits, and micro-finance.
Moreover, at the global scenario, this announcement complements the activities of the Global Alliance of Clean Cookstoves and the agenda of the Climate and Clean Air Coalition (CCAC). Launched in 2012, the CCAC is the first global effort to treat short-lived climate pollutants—s uch as black carbon, methane and many hydrofluorocarbons—as a collective and urgent challenge. One cost-effective method of reducing black carbon that the CCAC has identified is through the promotion of improved cookstoves. ICIMOD is already a non-state member to this coalition, and Nepal has shown considerable interest in joining as a state member. As the issue of black carbon picks up on the global scale, and with an effective option already at hand for mitigating black carbon emissions, Nepal should ambitiously move forward to reap benefits from regional and global efforts and improve the health of rural communities.
The author is Environment Officer for the Mountain Environment Regional Information System at ICIMOD.