Green Steps

How to transform your organic waste into energy, Naoden and Enerpro,

Two study cases at an industrial scale, Nantes

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- October 2016 -

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#Nantes #Energy #Waste #Industries

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Let's imagine you are a farmer, a manufacturer, and you have on one side tons of waste to treat everyday, from your animals or your factory, and on the other side a huge bill of electricity each month. What if you could get rid of the waste and reduce your electricity bill in one action? We met in Nantes two young start-up who are offering solutions at an industry's scale.

 

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Naoden/ from wood waste to energy

Naoden was launched in 2015. They work to create small plants which produce both electricity and heat from wood gasification. We met them with their first prototype, based in the South of Nantes, on a fruit and juice manufacture, les Coteaux Nantais.

 

In May, les Coteaux Nantais decided to invest in the prototype, installed during the summer, and which will be used this winter for the first time to heat the factory (58kWth expected) and produce electricity (30kWe expected). The factory has an extra waste of wood pallets, which are currently useless and are stored in huge stacks outside the building. For the first month, the wood chips used will come from local industries, but they will then use the old pallets as fuel for heating and producing electricity.

The prototype is made from three containers, installed on the parking lot nearby the factory. The first container store the wood chips, and is easily movable by trucks to be refilled. It is linked to two other containers, where the engines are. The wood is heated and gasified. The gas is then firstly cleaned to get rid of particles. The hot gas then goes through two heat-exchanger, in order to heat both air (used for gasification), and water (for the heating system). The gas is finally sent to the engine which will produce electricity. The extra heat from the smoke will also be used for heating, and the smoke goes through a filter before it is extracted.

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This system is mostly interesting for industries which produce, as les coteaux Nantais, their own wood waste, or which are situated on isolated locations, with a lack of electricity. A wood factory for instance, can provide its own wood chips, and use the electricity and the heat for drying wood. The energy is produced according to the factory's need.

 

Enerpro / from poo to heat or electricity

 

Another start-up, Enerpro, imagined to transform organic waste into energy, through a methanisation tank. The prototype is more widely used in farms. The droppings and organic contents thrown by animals are directly collected and sent to the methanisation tank, where it slowly disintegrate. The process creates methane, which is extracted.

The methane can be turned into electricity or heat. It can also be stored in a container. In the farm in Sizun in the French region of Finistere, the energy produced enables farmers to heat the calves' milk. For the  cheese dairy la ferme du Meunier, in the Morbihan, the methane enables to heat the water of the factory, and dry cereals.

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The system could also be put into place for a restaurant with waste of food, or even for single housing. The gas can be directly used for cooking, or turned into heating or electricity. It is then very similar to a septic tank, but with the benefit of producing energy from your simple waste. It also enables producers to be more autonomous of energy within the factory.

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Those case studies illustrate that circular economy can work at several scale, including one industry's scale. Those projects are rather innovative and isolated cases but can provide solutions for an isolated environment with difficulties to provide energy: in the mountains, or for electrification of Africa, for instance.

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Sources:

http://www.naoden.com/

http://www.enerpro-biogaz.fr/

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Images: Quentin Aubry, photos Honorine van den Broek