Basic Energy Services - Improved Stoves

Basic Energy Services in a Nutshell: Context| Basics | Energy Systems

Overview

"A stove is a device that generates heat from an energy carrier and makes that heat available for the intended use in a specific application.The combination of heat generation and heat transfer enables a cook stove to perform the purpose of cooking food fit for human consumption". Cook stoves are considered “improved” if they use less energy and/or if they emit less smoke compared to a more traditional stove.

Stove Efficiency

Clean Cookstove in Chiguata, Arequipa, Peru

Improved cooking stoves (ICS) are considered to save 40-60% of firewood as compared to the traditional three stone fire. Whereas for bigger stoves that are used at an institutional level the level of energy saving can be up to 70% of firewood if used correctly. Although specific fuel consumption can be compared to either (a) a benchmark or (b) the specific consumption of another stove.

Examples:

• Stove A consumes less fuel (for a specific standardized task) as indicated in the benchmark (e.g. 80g of charcoal per kg food prepared in a controlled cooking test)
• Stove A consumes 40% less fuel than stove B per liter boiled water (in a 5l Water boiling test)
  

While focusing on relative performance of stoves, the assessment of stove efficiency is circumstantial. For instance, a clay stove is perceived as an efficient stove in households with open fire places and as an inefficient stove in households which are using e.g. a rocket stove.

Stove Types

The production and commercialization of ICS has been observed to large extents in China and India, where governments have promoted their use, and in Kenya, where a large commercial market developed.

There are many different types of stoves worldwide. With this diversification, a stove needs to meet the site-specific constellation determined by the available fuels, climatic conditions and preferences of users in the local culture. For instance, people in rural areas use different fuels and may have different cooking needs than people in urban or semi-urban areas. Thus, stove designs reflect global diversity.

With the diversity of the cook stoves, there are different aspects that distinguish the stoves, this include:

• Fuel: firewood, charcoal, other solid biomass, liquid biomass, biogas, non-biomass fuels;
• Construction material: mud, fired clay, bricks, cement/concrete, metal, isolation materials (vermiculite, ceramic wool, refractory bricks, air…);
• Mobility: portable stoves built elsewhere and transported to user - or fixed stoves that have to be constructed on site.
• Pot sizes (from small to big individual households sizes, medium to large pots for restaurants, enterprises or social institutions)
• Pot shapes and materials (round bottom/flat bottom pots, clay or metal, pots with or without handles and/or legs, frying pans, etc.)
• Numbers of pots to be used at a time (pot holes for one or several saucepans)
• Numbers of fires (one combustion chamber or several ones)
• Batch-feeding or continuous feed of fuel
• With or without a built-in chimney to remove emissions from a kitchen
• Affordability (to suit the range of economic means of users from low-cost to more expensive)
• Place of manufacture (national production or imported)
• Other uses of a stove e.g. space heating, lighting
  

Further Information

• Cooking Energy Compendium: 25 years of knowledge and experience in developing countries GIZ Eschborn, 2011
  
• Fact sheets Improved Stoves
  
• A Documentation of Improved and Traditional Stoves in Africa, Asia and Latin America Westhoff; Germann, 1995
  
• Cooking Energy. Why it really matters if we are to halve poverty by 2015.
  
• www.giz.de/hera