Last updated: 13 April 2017
By using the renewable and emissions-free energy from the sun, solar cooking does not have the negative environmental impacts and requirements of traditional cooking methods, which include air pollution, exhausting natural resources for solid fuel (wood, charcoal, etc.), and spending significant time gathering and/or processing solid fuels. Instead, solar cooking allows the user to:
- Cook without emitting respiratory disease-causing smoke into their homes and surrounding area
- Reduce deforestation by minimizing the need for solid fuel
- Save time for other activities such as education, income generation, and spending time with friends and family
In many parts of the world, developing countries in particular, a three-stone fire—where a pot or pan is placed atop three-similarly sized stones surrounding a fire—remains the most common method of cooking. Such a stove is incredibly inefficient; it requires a large amount of wood and generate a relatively small amount of useable heat, as the majority of the heat does not reach the cooking pot. As a result, the user is required to either purchase a significant amount of solid fuel, which is expensive, or gather the required fuel on a regular basis, which is time-consuming and possibly dangerous due to the need to leave the safety of the user’s home or village. This gathering of fuelwood often leads to significant deforestation in the surrounding area, the impacts of which include erosion, destruction of animal habitats, and a loss of trees to absorb carbon dioxide (CO2), a major contributor to climate change.
Three-stone fires also emit significant amounts of CO2 and other gases such as carbon monoxide, the latter of which stays in the atmosphere longer than CO2 and is and is an even greater contributor to climate change. These stoves also emit particulate matter, such as black carbon, which not only contributes to climate change, but respiratory disease as well.
While inexpensive to construct, the cooking efficiency of three-stone fires is lacking as only about 10% of the heat generated is transferred to the pot with the rest being lost. This requires solid fuel to be purchased and/or gathered frequently, leading to environmental degradation from charcoal production and the stripping of areas of combustible trees and plants.
Use of natural resources
As described above, traditional cooking fires are extremely inefficient. Even “fuel-efficient” or “improved” cookstoves have been shown to use comparable amounts of solid fuel to three-stone fires in certain situations and not significantly reduce black carbon emissions in the field. When sources of fuelwood begin to disappear from overuse, smaller bits of foliage often start to be collected until they too are depleted. This constant and extended harvesting of biomass leaves areas barren which reduces or simply eliminates the means for natural regrowth and can cause erosion in the affected area.
The emissions of three-stone pose not only a health risk to the user and bystanders, but they contribute to global climate change as well. Black carbon and methane are all major contributors to climate change and are the primary emissions of open cooking fires.
With significant fuel use and negative impacts on climate change, the three-stone fires used by three billion people present dangers to the environments where they are used as well as the world at large. One solution is to use clean and efficient solar cookers whenever possible which only require solar energy to operate. Solar cookers benefit the environment by:
- Using clean, renewable, and readily available solar energy as fuel
- Preserving natural resources by not requiring the use of wood or other biomass fuels to cook
- Not producing dangerous emissions which pollute local environments and contribute to climate change
- ↑ A Comparison of Wood-Burning Cookstoves for Uganda: Testing and Development (Improved Biomass Cooking Stoves)
- ↑ Health and Climate-Relevant Pollutant Concentrations from a Carbon-Finance Approved Cookstove Intervention in Rural India (American Chemical Society)
- ↑ Household air pollution and health (World Health Organization)