Standards for Improved Cookstoves
Cookstoves vary greatly in technical performance across models and modifications. In order to measure the benefits of improved cookstoves and to allow for comparisons between models, it is necessary to conduct tests. For this, a definition what constitutes an improved cooking stove is mandatory. And only with a harmonized approach and benchmark according to international regulations stove testing becomes significant in an international context and between organizations and labs. That’s why within the last few years international standards are being developed jointly by the international stove community.
International standards are desirable to enable a global comparison of stove performances. However, there is a danger that cheap stoves with a low performance in relation to these standards are no longer promoted even though for poor households they could still be a relevant improvement compared to the baseline technology.
The International Standard ISO
It has been developed and approved by international experts from 45 countries.
This standard specifies testing and reporting protocols to measure and evaluate emissions, efficiency, safety and durability of cookstoves in a lab setting. It is applicable to stoves used for cooking or water heating in households, small enterprises, and institutions. For solar cookstoves, the provisions of the standard are applicable only for evaluating cooking power, safety, and durability. Based on experience with previous protocols, customization in reporting is possible, while still maintaining harmonization in testing, to cater the need of better reflecting local context and practices.
The standard replaces an ISO International Workshop Agreement from 2012. For more information on the history of standard development, see also text below.
The accompanying part 2, Clean cookstoves and clean cooking solutions – Vocabulary gives a precise terminology for cookstove technology and testing. It specifies laboratory measurement and evaluation methods for the particulate and gaseous air pollutant emissions of cookstoves.
A third part, a technical report, will be published in the coming months. It will set voluntary performance targets, or tiers, and provides guidance on how to understand and interpret lab test results.
Also under development is a guidance on field testing methods for cookstoves.
History - The Road to an International Agreement
Over the last decades, minimum technical standards for improved stoves have varied across countries and programs, with many countries lacking any sort of technical standards for improved cooking stoves. Furthermore, different testing methods made comparisons between different stove models difficult. This, of course, did not help ensure that stoves disseminated with the label “improved” were actually effective.
In 2011, the Partnership for Clean Indoor Air (PCIA) organized a 5-day forum in Lima, Peru for practitioners and experts on clean and efficient cooking technologies and fuels. One result of this forum was the signing of the Lima Consensus, a resolution to develop a standardized test protocol for measuring technical performance and a standard for improved cookstoves.
As a way forward, the community agreed to go through the process of developing an agreement in workshops, which would then be certified by the International Organisation for Standardisation (ISO). Based on this consensus, the International Workshop Agreement (IWA) was drafted by PCIA in cooperation with the Global Alliance for Clean Cookstoves (GACC) to be discussed and affirmed in The Hague, Netherlands in February 2012.
After review at the workshop, the revised International Workshop Agreement (IWA) was unanimously approved in February 2012 by over 90 participants from 22 countries. The IWA was a first step towards a formal ISO standard and served as an interim international guideline. The goal was to provide a common and easy-to-understand terminology for governments, donors, investors, and consumers to make decisions about technology options. For this, performance categories such as fuel use, total emissions, indoor air quality, and safety were developed. For these categories, tiers have been developed, so that stoves can be classified into different quality levels. The tiers range from tier 0 having no improvement over the baseline stove (usually the 3-stone fire) to tier 2 having substantial improvements and tier 4 stretching goals for targeting ambitious health and environmental outcomes. The tiers boundaries are defined by quantitative values determined by laboratory testing, based on the Water Boiling Test (WBT 4.2.3) and the Biomass Stove Safety Protocol 1.1.
Please note, the tiers were not designed to be combined. There is no “tier 2 stove.” Instead, the indicators are kept separate to provide flexibility for governments and organizations to set different goals. For example, a stove might be “tier 3 for efficiency, tier 2 for indoor emissions, tier 3 for total emissions, and tier 4 for safety.”
There are several national standards for cookstoves already in place. For example:
- Indonesia (2013): Biomass Stove Performance
- Bolivia (2010): Cocinas mejoradas - Condiciones técnicas mínimas de instalación, funcionamiento y de rendimiento
- Peru (2009): Reglamento para la evaluación y certificación de la cocina mejorada
- Uganda (2007): Energy efficiency stoves — Household biomass stoves — Performance requirements and test methodsKenya (2018): Biomass stoves - Performance requirements (check the Kenya Bureau of Standards Online Catalogue)
- Kenya (2014): Domestic biogas stoves – Specification (check the Kenya Bureau of Standards Online Catalogue)
- The Global Alliance for Clean Cookstoves is leading the whole standardization process and regularly publishes updates: www.cleancookstoves.org
- The Global Alliance for Clean Cookstoves offers a FAQ and Stakeholder Guidance document on the new international standard. http://cleancookstoves.org/resources/556.html
- The International Workshop Agreement is the interim international guideline for stove performance and part of the ISO process. For the tiers, see pages 10 and 11.
IWA 11:2012 Guidelines for evaluating cookstove performance.
- Reporting Form - IWA Tiers and Test Results
- The Stove Performance Inventory, developed by the Berkeley Air Monitoring Group in partnership with the Global Alliance for Clean Cookstoves, contains data from over 600 sets of performance tests. Berkeley Air Monitoring Group – Stove Performance Inventory Report 2012
- For test protocols see also Testing of Woodfuel Stoves on energypedia
This article was originally published by GIZ HERA. It is basically based on experiences, lessons learned and information gathered by GIZ cook stove projects. You can find more information about the authors and experts of the original “Cooking Energy Compendium” in the Imprint.
- https://www.iso.org/standard/66519.html Cite error: Invalid
<ref>tag; name "https://www.iso.org/standard/66519.html" defined multiple times with different content
- Global Alliance for Clean Cookstoves, http://cleancookstoves.org/about/news/01-01-1990-iwa-tiers-of-performance.html
- IWA 11:2012 Guidelines for evaluating cookstove performance http://cleancookstoves.org/binary-data/DOCUMENT/file/000/000/6-1.pdf
- Global Alliance for Clean Cookstoves, http://cleancookstoves.org/technology-and-fuels/standards/iwa-tiers-of-performance.html