Turning rice straw into cooking fuel for air quality and climate co-benefit in selected GMS countries

Most countries in the Mekong Region are agrarian developing countries where rice is a staple food that provides 50–80% of the total calories consumed. A huge amount of rice straw (RS) is generated in each crop cycle. For faster crop rotation, most farmers in the region prefer open burning (OB) of RS in the field to clear the surface biomass. A large portion of RS residue is burned within the region. RS residue is a potential biomass resource specifically for the region. Currently, various options for using RS are available with different levels of acceptance from farmers and community. The suitability of such technologies, to be offered to farmers in order to counteract the OB practice, needs to be considered and explored based on economic, social, and cultural factors particularly to gain acceptance from the end users.

Research questions

The research project will attempt to answer the following research questions:

1.     What is the status of RS management in the target countries?

2.     What are the RS derived fuels and cookstoves that technologically suitable and economically/socially acceptable by local farmers in the Mekong Region countries?

3.     What are the potential impacts on emission reduction of air pollution and climate forcers if such measures are multiplied in the selected countries?

4.     What are effective policy options in enhancing multiplication of proposed measures to minimize the OB practice?


Most Mekong countries do not have specific national policies to counteract the crop residue OB practice. Therefore, it is very important to facilitate effective communication with policy makers at different levels using various platforms such as technical/policy dialogue and consultative meetings.

The project team ensures that the boundary partners to be involved since the project kick-off meeting. Alternative efficient policy tools, such as market based instruments (MBI) and educative (persuasive, awareness, public participatory, etc.) rather than only the command and control (CAC), should be further explored and discussed with policy makers and other stakeholders in the various communication channels in order to achieve main goals of the research project, i.e. turning RS to cooking fuel or reduce OB. This project would contribute to achieve the major goals of Mekong countries (poverty alleviation, employment, and growth) and at the same time reduce stress on the environment and regional climate.

Moreover, the research project survey will help to understand local specific conditions that can be used together with the input from stakeholders gained at various workshops in the design and selection of technologies. Technology “products” are then demonstrated to the farmers to gain their perception and acceptance.

The concrete objectives of the proposed research project are:

1.     To survey the current generation and use of RS in selected Mekong countries.

2.     To study RS derived fuel-processing technologies to produce solid cooking fuel (pellet/briquette) and their usage for cooking purposes.

3.     To adapt a preliminary design of a RS derived fuel and cookstove system.

4.     To assess the acceptability of the proposed fuel-cookstove system to local farmers.

5.     To analyze efficacy and potential co-benefits of the technology applications on the Mekong regional scale on air quality and climate forcing.

6.     To create an enabling environment for multiple application/installation of the fuel cookstove system by disseminating and communicating the findings to the stakeholders such as rural community, policy makers and academic institutions etc. in the Mekong countries.


Task 1: Benchmarking on RS generation, use, and open burning in target countries

Survey of current RS residue generation and usage will be conducted in the selected agricultural areas in Cambodia, Vietnam and Thailand. Several representative agricultural areas will be selected. The survey expects to obtain key information on: 

•    Typical crop (paddy) to residue ratio (specific for RS) and other characteristics of RS samples such as density, carbon content, etc. for various popular cultivars.

•    Typical generation factor of RS per area (metric ton or tonne/ha) estimated using crop to product ratio (CPR) values and paddy yield per ha. 

•    Existing situation of RS usage (for example, organic nutrients, feed stock, mushroom growing and any other possible options currently practiced).

•    Portion of RS being burned in the field and burning practices.

•    Motivation of farmers to burn RS and their perception on the negative impacts of OB practices.

•    Willingness to implement measures that give benefits in many aspects not only for farmers but also environment.

Task 2: Technology assessment on RS pellets/briquettes mills

A complete literature review on the available technologies to convert bulky RS into pellets/briquettes will be carried out under this task. Rice straw has less moisture content (15–20%) so it is suitable to use for generating heat and electricity or converting into fuel. Characterization of RS samples taken from the region will be done including the proximate analysis. Further investigation will be done particularly for the solidification process of RS.

Task 3. Prototype development and testing of RS derived fuel cookstove

Direct combustion of RS is not desirable because of its high ash content, less fixed carbon and produces a lot of smoke hence not good for health. On other hand, due to the presence of high volatile matter in RS the pyrolysis and gasifi- cation will be a better way to utilize rice straw after densification in the form of pellets or briquettes. Therefore, it is important to take initiatives to design and construct a cook stove that is suitable to burn efficiently RS derived solid fuels.

Design and development of prototype of RS derived fuel cookstove system will be conducted based on the available cookstove technologies developed earlier at Energy FoS of AIT. 

Task 4: Socio-technological acceptance analysis

Many aspects affecting the uptake of proposed technology by local communities should be considered in the research project. Through the consortium members, the RS fuel-cooking system will be brought to farmers in the study areas for

trial use. Hands-on trainings to demonstrate the technology will be conducted in Cambodia and Vietnam. Set of questionnaires will be developed incorporating social, economy, technical and gender aspects and will be distributed to farmers following the demonstration. The survey information will be analyzed and possible inputs and suggestions from local farmers (focusing on women) will be considered in the evaluation of the RS fuel-cooking system. 

Task 5: Assessment of co-benefits of technology implementation to reduce field burning of RS

Firstly, emission inventory (EI) for the selected agriculture areas in the target countries will be compiled for base year of 2014 covering residential com- bustion and RS OB (base case). An emission scenario will be developed with the main assumption that farmers implement “zero burning” and use the RS derived fuels for cooking by the developed cookstove. The emission reduction in this scenario, from base case emission, will be quantified and co-benefits on air quality and climate will be estimated using global warming potential (GWP).

Task 6: Results dissemination and capacity building

A synthesis report on current status of RS residue generation and utilization in three countries will be produced to summarize the results of surveys conducted in the task 1. Publications of innovative findings will be made in international journals as well as a book chapter coordinated by the SUMERNET. Two national workshops will be conducted in Cambodia and Vietnam. For capacity building, students from all consortium partners will be involved in the project activities and two hands on trainings on the RS pellet-briquette preparation and cook-stove operation will be conducted in Cambodia and Vietnam for local farmers.

Policy impacts expected

1.     Strengthened enforcement of the existing non-open burning policy in Thailand.

2.     Increased awareness of policy makers on the impacts of RS field burning thus effort can be initiated and communicated among related departments in the target countries.

3.     Initiation of policy dialogue from the governmental institutional side with the support of policy briefs produced from the research project activity.

4.     Increased awareness of the importance of air quality and climate policy integration particularly in the Mekong agriculture sector.

Lead contact

Prof. Nguyen Thi Kim Oanh

Asian Institute of Technology (AIT), 58 Moo 9, Km. 42, Phaholyothin Highway Klong Luang, Pathumthani 12120, Thailand