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3.3.4 Agrobioenergia

Agrobioenergia is an agricultural cooperative society established in 2005 with the aim of building a biogas plant that will use biomass coming from the 25 associated farmers (corn and agricultural by-products).

Through anareobic digestion, biomass produces digestate and biogas:

  1. digestate is used as ferilizer for the fields of the associated farmers
  2. žbiogas is sent to the cogeneration plant, where energy power and heat are produced.

Energy power is sold to the grid while heat is used for keeping the biological condition inside the plant, for the heating of offices and, through a small district heating, for the heating of the nearest farm.

The plant has been built in 2010, when national incentives for biogas production where high; these incentives last for 15 years. The challenge for Agribioenergia is to make the entire process more resource efficient and self-sustained from an economic point of view, before the end of the incentives. At the beginning, the biogas plant was entirely fed with corn coming from dedicated energy crop; today corn represents 30% of the ”diet” of the plant (the rest is represented by agricultural by-products); this has been an economic improvement as by-products are cheaper than crop but also an environmental improvement as biomass deriving from dedicated culture has a higher impact than by-products.

Heat power coming from the cogeneration plant is nowadays not entirely and not continuously used: they will soon build a plant where herbal medicines (deriving from their organic agriculture) can be dried thanks to the heat coming from the CHP plant.

The biogas plant has a lot of environmental benefits:

  1. žElectric and heat energy is produced from renewable resources
  2. žCogeneration with heat recovery has the highest energy efficiency in energy production
  3. žBy-products or agricultural waste are used as biomass instead of beeing sent to disposal
  4. žEnergy production is local, with final users near to the plant and a very short supply chain for biomass coming from farmers
  5. žChemical fertilizer has been replaced with the digestate, with lower environmental impact.

All these environmental benefits have also a positive impact in cost saving:

  1. žCost related to purchasing of chemical fertilizer has been eliminated (almost 300.000 euro/years)
  2. žCosts related to transport of biomass from producers (farmers) to the plant are very low due to the short distances
  3. žCost related to disposal or treatment of agricultural waste has been eliminated.

Furthermore, drying the herbal medicines with the heat of the CHP plant has opened a new market to the group of farmers.

Agribioenergia farmers went to visit plants in other countries in order to know the best practices, but then they have re-thought the project based on their specific needs, because each situation has its own specificity and best practices cannot be replicated anywhere. So, the lesson learnt is to get a deep knowledge of available technological solutions and, at the same time, to be aware of the local situation (needs of the farmers, kind of crops, type of soil, geographic distribution of interested subjects, agricultural resources available, market conditions...). Financial incentives are necessary but they should be meant as only a starting point: enterprises should think on a long term period and should design a self-sustained process, in view of the expiring of the incentives.