The effectiveness of anaerobic digestion of bio-waste in replacing primary energies: An EU28 case study

Biodegradable fraction of waste is generally recognized as a sustainable source for renewable energy production and anaerobic digestion (AD) is the most used process for this purpose. The majority of AD facilities currently operating in the EU28 are equipped with gas engines fuelled by the biogas for production of electrical energy. There is growing interest in other energy recovery options whose implementation will rise significantly in the near future. AD of bio-waste can play an important role for the implementation of EU policy for renewable energy, i.e. EU 2030 goals, and waste management, i.e. recycling target. From this perspective, the present study performed an assessment of the capability of AD facilities currently operating in the EU28 for bio-waste processing, in replacing other fuels, energy and raw materials. For this purpose, the effectiveness of different energy/fuel recovery schemes were analysed and discussed. A life cycle approach was adopted defining a specific indicator, the hybrid primary energy (HPE) (MJ/Mg) based on the exploitation of the cumulative energy demand (CED) (MJ). Future research trends for AD were also presented and discussed.