How biogas in Vietnam is saving the rural population money, improving health outcomes and benefiting the planet — all at once.

Vietnam has a human population around 1.5 times that of the UK, but a pig population some six times greater. As traditional fuel prices have become increasingly more expensive and unstable in recent years, the rural Vietnamese have turned to something all the more accessible to meet their energy needs, namely, animal waste.

What may be surprising to some is that this decision — to use animal waste as an energy resource — is a sustainability jackpot. The technology employed in Vietnam is managing to solve energy shortages, reduce emissions, slow deforestation and cut air pollution, ALL AT THE SAME TIME. Biogas is fast becoming a life-changing fuel for the rural-poor and for the planet.

Using biogas is not new in Vietnam; the last 60 years have seen continuous research, and big projects have attracted major investment. The largest project to date — known as the Biogas Programme in Vietnam, or BPV — has constructed over 150,000 biogas digesters in Vietnam, providing clean, reliable energy for more than 790,000 rural individuals. This project has reduced Vietnam’s greenhouse gas emissions by over three million tonnes of CO2 equivalent — a reduction equal to roughly 1 million tourist flights from London to Hanoi.

Speaking the The Climate, Michelle Lowery, Communications Manager at Nexus for Development, an international not-for-profit organisation involved in the BPV, spoke of the project’s accomplishments: “The success of the Biogas Programme has been a testament to a lot of hard work from our project partners SNV Netherlands Development Organisation and the Ministry of Agriculture and Rural Development (MARD) in Vietnam.

“Together we were working to address the waste management issue, which was resulting in serious health issues in local communities, extreme pollution and significant greenhouse gas emissions.

“Our aim was to bring our expertise in carbon financing to secure international funding through the sale of carbon credits, which would enable the project implements to work with local communities to build biogas digesters. We’re incredibly proud to say that over the ten-year period of the project we unlocked $10 million, which helped fund over 179,000 biogas plants in 55 provinces across the country.”

How it works

Biogas plants, or biodigesters, replace smoky cooking fires. Human and animal waste is collected in a reservoir, and as the waste decomposes, it releases methane gas, which is piped into homes and used for fuel. The remaining waste can be used as an effective fertiliser on the farm.

Building a biogas digester in Vietnam (Image by Biogas program in Vietnam/Nexus for Development)

Simpler than it sounds

Despite sounding technical, this can be achieved on a very small and accessible scale. A family with just three cows or seven pigs can use a biogas plant to generate enough energy to meet their basic domestic needs.

If families have no livestock, other waste products, such as rice straw (a byproduct of rice production) and water hyacinths (a type of river weed), can be harvested. Ultimately, biogas can be obtained from the parts of farming that no one else wants.

Once the biogas reaches the kitchen, it’s easily put to use. Klaus Sieg’s article titled “Biogas in Vietnam: Simple Technology with a Major Impact”, describes the situation in rural Vietnam:

“Le Thi Thanh Thuy stands among the woks, pots, and pans on her tiled kitchen floor and points to the pressure gauge on her small biogas digester. The simplicity of the technology is remarkable. A wooden board, a transparent plastic tube full of water, and a few markings. ‘When the pressure in the digester gets too high, I have to cook,’ she says. If she does not use the biogas, it can escape from the fermenter through a pressure release valve. ‘But that almost never happens because we always need it all,’ adds the farmer, who lives in Khanh An village in An Giang province in the Mekong Delta.”

More about the benefits

Clean energy, of course, is the main benefit. Biogas stoves help to reduce methane emissions that would otherwise escape from landfills or manure lagoons. By using this methane as a fuel, its climate impact is reduced by converting it to CO2, which is around 34 times less potent as a greenhouse gas.

Affordable energy is also a benefit; households no longer need to purchase fuel or collect wood, saving an average of $120 a year. This has the added benefits of reducing deforestation, as locals no longer have to rely on native forests as an energy source. In fact, studies in Vietnam have found that women in biogas households save 40 minutes on cooking and 70 minutes on collecting fuel each day. Additionally, the leftover ‘bio-slurry’ can be used as a fertiliser, saving $62 a year.

Health and wellbeing for people is a major concern, and household air pollution from open combustion has been found to be the third largest cause of premature mortality. Biogas can help to prevent this risk.

Future in Vietnam

As things stand, the government in Vietnam does not offer a guaranteed price or contract for biogas producers, leaving projects mostly small-scale and disconnected from the grid. If biogas could be scaled up and converted into electricity on a larger scale, it has the potential to facilitate massive progress in Vietnam and, if rolled out in other nations too, around the world.