Cooking fuel is any energy source used to heat food, from a bundle of firewood on an open flame to natural gas piped into a kitchen stove. The World Health Organization tracks six main categories globally: electricity, gaseous fuels (liquid petroleum gas, natural gas, and biogas), kerosene, biomass (wood, crop residues, and animal dung), charcoal, and coal. Which fuel a household uses shapes daily life in profound ways, affecting health, household budgets, time spent gathering fuel, and the surrounding environment. Today, 2.1 billion people worldwide still rely on polluting cooking fuels, mostly in Sub-Saharan Africa and Asia.
The Main Types of Cooking Fuel
Cooking fuels fall into two broad camps: clean fuels and polluting fuels. Clean options include electricity, natural gas, liquefied petroleum gas (LPG), and biogas. Polluting options include wood, charcoal, coal, crop waste, animal dung, and kerosene. The distinction matters because polluting fuels release large amounts of smoke and tiny particles into the air when burned, especially indoors.
Solid fuels like wood, charcoal, and coal are the oldest and most widely used cooking fuels on the planet. Wood remains the dominant fuel in rural communities across much of Africa and South Asia. Charcoal, made by slowly burning wood in low-oxygen conditions, burns hotter and more steadily than raw wood but still produces significant indoor smoke. Coal is less common for household cooking but is used in parts of China and other coal-rich regions.
Liquid fuels include kerosene and ethanol. Kerosene stoves were once seen as a step up from wood fires, but kerosene still produces harmful fumes and carries a fire and poisoning risk. Ethanol-based fuels are a newer alternative that burns more cleanly, though availability remains limited.
Gaseous fuels like LPG and natural gas are the most common clean cooking fuels in middle- and high-income countries. LPG is delivered in portable canisters, making it accessible even in areas without gas pipelines. Natural gas, piped directly to homes, is the standard in many urban kitchens worldwide. Biogas, produced from decomposing organic waste in a digester, is a renewable gaseous fuel gaining traction in rural communities.
Electricity powers a range of cooking appliances from conventional coil burners to induction cooktops and microwave ovens. Electric cooking produces no emissions at the point of use, though its overall environmental footprint depends on how the electricity is generated.
How Efficiency Varies by Fuel
Not all cooking fuels convert their energy into heat with the same effectiveness. A traditional three-stone wood fire, the kind still used by hundreds of millions of households, typically converts only 10 to 15 percent of the wood’s energy into usable cooking heat. Most of the energy escapes as smoke, light, and wasted heat radiating away from the pot.
Gas stoves are a major step up but still lose more energy than many people expect. A typical gas burner in the United States operates at roughly 40 percent efficiency, meaning more than half the energy in the fuel never reaches the food. Electric stoves perform better at around 80 percent efficiency. Induction cooktops, which use magnetic fields to heat the pot directly rather than heating a burner first, push efficiency even higher because almost no heat is lost to the surrounding air. For households trying to reduce energy costs, the type of stove matters as much as the type of fuel.
Health Risks of Polluting Fuels
Burning solid fuels indoors is one of the leading environmental health risks in the world. Household air pollution from cooking with wood, charcoal, coal, and dung is responsible for an estimated 2.9 million deaths every year. The smoke from incomplete combustion contains fine particulate matter, carbon monoxide, and dozens of other toxic compounds that fill enclosed kitchens, often for hours each day.
Breathing this smoke over months and years triggers a cascade of damage in the lungs. Fine particles irritate and inflame the airways, breaking down tissue over time. The health consequences are severe: chronic obstructive pulmonary disease (COPD), lung cancer, head and neck cancers, tuberculosis, and acute lower respiratory infections in children. Women and young children bear the heaviest burden because they tend to spend the most time near the cooking fire. In many communities, respiratory infections linked to cooking smoke are among the top killers of children under five.
Environmental Impact
Different cooking fuels leave very different carbon footprints. The U.S. Environmental Protection Agency puts natural gas at about 117 pounds of CO2 per million BTU of energy, LPG (propane) at 139 pounds, and fuel oil at 163 pounds. These figures capture only the carbon released during combustion, not the full lifecycle of extracting and transporting the fuel.
Solid biomass fuels present a more complex picture. In theory, wood is carbon-neutral if new trees regrow to absorb the CO2 released by burning. In practice, demand for cooking fuel drives deforestation in many regions, meaning the carbon is never recaptured. Charcoal production is particularly destructive: converting wood to charcoal releases large quantities of greenhouse gases during the process itself, and charcoal demand is a major driver of forest loss across tropical Africa. Coal, the most carbon-intensive fossil fuel, produces the highest emissions per unit of cooking energy.
Electric cooking powered by renewable sources like solar or wind produces virtually zero emissions during use. Even electricity from a mixed grid tends to produce fewer localized pollutants than burning fuel directly in the home.
Clean Cooking Alternatives
The transition away from polluting fuels centers on three main pathways: LPG, electricity, and biogas.
LPG is the fastest route to cleaner cooking for many households in developing countries because it works with relatively inexpensive portable stoves and doesn’t require a power grid. The main barriers are the recurring cost of refilling gas canisters and the logistics of delivering them to remote areas.
Biogas digesters offer a renewable option suited to rural households, particularly those with livestock. These systems break down animal manure, food scraps, or crop waste in a sealed tank, producing a methane-rich gas that pipes directly to a cookstove. Beyond providing clean fuel, digesters reduce waste and produce nutrient-rich fertilizer as a byproduct. Adoption has grown in parts of South and Southeast Asia, and researchers are exploring their potential in the Pacific Islands and Sub-Saharan Africa.
Solar cookers use reflective panels or parabolic mirrors to concentrate sunlight and generate cooking temperatures without any fuel at all. They work well for slow-cooking tasks in sunny climates but cannot function at night or on overcast days, which limits them to a supplementary role in most households.
Improved cookstoves represent an intermediate step. These are designed to burn wood or charcoal more efficiently and vent smoke through a chimney or flue, reducing indoor pollution. They don’t eliminate the problem, but they can cut fuel use and smoke exposure significantly compared to an open fire.
Global Access and the 2030 Gap
The United Nations included universal access to clean cooking under Sustainable Development Goal 7, with a target of ensuring affordable, reliable, and modern energy for everyone by 2030. Progress has been painfully slow. As of 2024, 2.1 billion people still lack access to clean cooking fuels and technologies, a number that has remained largely flat in recent years. The WHO reported that progress on basic energy access actually reversed for the first time in a decade.
At current rates, roughly 1.8 billion people, about 22 percent of the projected global population, will still be cooking with polluting fuels in 2030. The shortfall is concentrated in Sub-Saharan Africa, where population growth is outpacing the rollout of clean cooking solutions, and in parts of South and Southeast Asia. Closing this gap requires not just cheaper technology but also distribution networks, financing for low-income households, and cultural adaptation, since cooking practices are deeply tied to food traditions and daily routines.
International standards from the ISO now provide a framework for rating cookstoves on efficiency, emissions, safety, and durability, with testing protocols for both laboratory and real-world household settings. These tiered performance ratings help governments and aid organizations identify which stoves and fuels actually deliver meaningful health and environmental benefits, rather than relying on marketing claims.