Interview : "There is a keen interest in small scale digesters"

Biogasanlage in Deutschland mit Getreidefeld
© Animaflora PicsStock/

Anaerobic digestion on a small scale was long considered unprofitable. Why did that change?

Maxime Lemonde: Around the world, small-scale digestion is not defined the same way. In North America or Europe, we will say it's a small-scale digester when it's under 5000 tons of waste per year. This means that a small farm or a small food producer will be small-scale digesters. In Asia or Africa, a small-scale digester will be a home digester for mainly human waste and some food waste. This means that when we talk profitability it's mostly for European and North American projects. The increase of subsidies, strict waste regulation, industry sensibilization are some factors why we are seeing more small-scale digesters.

How many AD are there worldwide?

Maxime Lemonde: There are millions of small family digesters in Asia and Africa (such as HomeBiogas but mainly in brick). When we are talking about full-scale systems (over 5000 tons per year) it's over 18,000 systems in Europe and over 2,500 systems in North America. To our knowledge, there are less than a thousand small and micro systems in Europe and North America.

Who is the target group?

Maxime Lemonde: Large food producers, small farms, and smaller municipalities might be tempted with small-scale digestion depending on where they are in the world. Regulations, subsidies, and environmental gains are the main drivers.

Where do you see the biggest market growth?

Maxime Lemonde: USA, France, UK, and Italy are generally good markets for the biogas industries meaning that there is probably room for small-scale growth.

What are the advantages and disadvantages of small-scale digesters?

Maxime Lemonde: Producing your own energy and fertilizer might be interesting for some developers and waste treatment might be the main reason for others. In good economic conditions, you should be able to generate a profit from the operation and an environmental gain. The main disadvantage is that operating an energy facility is rarely the core business of the development and comes with technical and operational challenges.

How do you see the future of AD? Will there be more small or even micro digesters or will there be a focus on large AD?

Maxime Lemonde: The main issue for systems run by households like home biogas is that the climate is a big part of the system operation meaning that it's not suited for a nordic climate but still represents a huge potential. Volume-wise large-scale AD will still dominate the volume of biogas to be produced globally. There is also an economy of scale to go with bigger plants.

About Maxime Lemonde and BiogasWorld

Maxime Lemonde is CEO of BiogasWorld, the largest commercial, technical and information Network of the Biogas Industry. Biogasworld is a knowledge-based company working to accelerate the biogas and RNG (biomethane) industry worldwide through our business generation platform & network. BiogasWorld aims to support all project developers and suppliers of the industry.

Maxime Lemonde is CEO of BiogasWorld.

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