The socio-economic value of biogas in Vietnam

Danish and Vietnamese researchers have set out to ensure cheap and sustainable energy for inhabitants in rural Asia using biogas plants, thereby hopefully elevating the living standards. Professor Jan Bentzen from the Department of Economics and Business at AU has taken on the task of weighing the benefits against the cost of implementing the technology.

In the rural part of the Mekong Delta there is no centralised power supply, and until now, most households and small farmers have relied primarily on firewood to meet their needs. But more than one million rural households still have no access to electricity, because the national power grid does not extend into the remote areas, or they cannot afford the connection costs of electricity.


However, while 35.000 households have started using small biogas plants that run on manure from pigs, manure has proven to be an inconsistent energy resource, as the amount of manure varies depending on the size and number of pigs within the household. Three pigs are considered minimum for running a household biogas plant. So far people have been reluctant to invest in biogas technology, fearing that at some point they will lack biomass fuel, and their investment will not have been worthwhile.


The possible solution: Waste rice straw

In a Danida financed development research project, together with Associate Professor Kjeld Ingvorsen from the Department of Bioscience at AU and a group of researchers and students from Cantho University in Vietnam, Jan Bentzen is working towards a solution that will enhance energy production in these rural communities.


The Vietnamese are in rich supply of waste straw from rice production, which is currently mostly disposed of by burning – an altogether non eco-friendly and polluting approach. But according to this group of researchers, rice straw may prove to be in fact a significant supplementary resource, because of its high energy content.


Adding rice straw to the manure biomass may help stabilise and enhance energy production, thereby creating further incentive for the rural population to invest in the biogas technology.


Social cost benefit analysis

Jan Bentzen’s project is to make an assessment of the socio-economic challenges related to the implementation of household biogas plants; to establish how biogas plants can generate value to society and, in turn, also to educate the farmers on how they will benefit from it. How much will it cost per family, how much will it take for them to gain the expertise to use the technology and, in the longer run, how is the technology to be marketed?

A group of students from the Can Tho University are conducting personal interviews with 160 peasants living in the area, focusing on establishing proof of positive social welfare effects of the biogas solution.


By interviewing those who already own a biogas plant and those who do not, the researchers will be able to map the personal circumstances, concerns and attitudes of the farmers as well as their overall energy use and requirements. “The interviewers collect background data, asking questions related to their levels of education, how many pigs they own and their current power supply,” says Jan Bentzen and continues.


“But given the cultural differences between us and them, it is also necessary to focus on the social aspects, gaining access to the inner connections. We need to learn, what does health mean to them, are they aware that they may contract lung diseases from using firewood in their kitchens, and is it at all a factor for them that this new source of energy is also energy-friendly.”

Social and economic reasons to invest

While some have been convinced of the benefits of biogas, most farmers remain reluctant to invest in the technology. According to Jan Bentzen, this is primarily due to financial concerns, but the researchers hope to be able to familiarise people in the communities with the equipment: “We have established that the biogas plants can run on rice straw. But they need to see that it works,” he says. 

Jan Bentzen makes it very clear that these farmers cannot afford to think in green solutions: “Out in the rural outskirts of the Mekong Delta they are not at all interested in the energy agencies’ directives on sustainability,” he explains. “They need to be convinced that the development will facilitate rather than impede their household economies, their daily lives and, possibly, affect their futures.”

 Expecting a positive and energy-friendly outcome

Jan Bentzen expects the outcome of his research to be positive, since the biogas technology is relatively simple and cheap to invest in as well as operate in the everyday, as it demands few resources from outside the local area. If successful, biogas plants will heighten the living standards for many people, contributing both to rural development and environmental protection.


If the Vietnamese embrace the biogas plant, they will avoid the health hazardous substances that circulate in their smoke-filled kitchens, when they fuel their ovens with wood. Moreover, burning firewood causes forest depletion, which will be avoided when substituting firewood with waste rice straw, which is an entirely sustainable and energy-friendly solution.


Finally, the researchers hope that the project will inspire more local, entrepreneurial activities. Biogas may in the future be used in the region for purifying drinking water and lighting their houses. All this may in turn help create a positive business environment that will hopefully affect the income and job opportunities in the region. 

More about the project (in Danish): Affald bliver til energi i Vietnam

Contact information

Jan Bentzen, professor
Aarhus Universitet, Department of Economics and Business - The Tuborg Research Centre for Globalisation and Firms
T: 87164992