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[su-re venture] How to stop "stop using biogas digester"?

"We are doing a biogas project in Sumatra. Most of the farmers who have installed biogas digesters are not using them after two years. What do you think this should be done?"

This is a question from Hanako (pseudonym) from Sumatra.

Hi, this is Takeshi, CEO and biogas promoter of!!

Today, I gave a keynote speech on Webinar on energy and waste issues and that was the last question I asked. I answered it with three solutions.

This 'disuse' problem is a trend we have seen in the last European Commissions projects (TRANSrisk and Green-Win 2015-18). In government projects, the majority of farmers stop using biogas digesters after two years. Even when combined with proper private sector projects, it is estimated that around 60% of the total number of biogas digesters in Bali projects are no longer being used.

Firstly, I state the purpose and current situation.


The biogas project aims to encourage more people to use biogas.

Current situation

Currently, around 60% of people will stop using biogas after two years.

The difference between the objective and the current situation is the problem and the way to close the gap is solutions. Considering mutually exclusive and collectively exhaustive (MECE), there are three possible problem and solution pairs.

  1. Introduce more people to the system because many people stop using digester.

  2. Make sure that items no longer used are used by another person.

  3. Reduce the number of people who stop using it.

The first response is to make biogas equipment cheaply and introduce it to a large number of people by "hitting them in the dark". Currently, a biogas digester for farmers in rural areas would cost between $3,000 and $5,000. Even with subsidies, it would cost around $1,000. And since it is made of concrete under the ground, it cannot be operated as mass production.

That's why our biogas digesters are introduced at about one-tenth the price of existing biogas digesters. Furthermore, the PVC bags of the biogas digester can be produced in bulk at the factory and then distributed, so there is the potential for mass production. In other words, a way of "hitting in the dark" to introduce more people to the digester is possible with's PVC-backed biogas digesters, even as more people stop using it.

Secondly, the PVC-backed biogas digesters could be a solution to "make what is no longer in use available for use by others". As they can be made in factories and delivered to farmers, they can also be delivered by farmers to factories if they are no longer in use. In particular, our biogas digesters are distributed free of charge to ordinary, less wealthy farmers. So, since they are not buying it, they could return it to us when they no longer use it.

The third, reducing the number of people who stop using it, is the best solution, but this requires a more advanced approach. The reason why people don't use it is that they don't feel the need to continue to use biogas. For example, the incentive for the introduction of biogas in Bali by a government group was to give away two cows. This was an incentive for installation, but not for continuous usage. Therefore, it would not be surprising if they lost interest in the biogas digester and stopped using it after receiving the cows.

If we can introduce incentives for farmers to continue to use biogas digesters, then farmers will continue to use them. For example, if we can verify that farmers have produced biogas and can pay them for it, that would be an incentive for them to continue to use biogas digesters. I'd like to link that to emissions trading. I will talk about that explanation at another time.

See you tomorrow!!

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