To achieve the targets of 32.5% energy efficiency by 2030 and climate neutrality by 2050, the European Union has set out two strategies: the first, which concerns energy system integration, aims to improve the management of plants and networks as a system; the second promotes hydrogen production, which plays a key role in the decarbonisation process.

These are strategic proposals that we at Hera Group have embraced with a major investment programme aimed at innovation and the upgrading of networks and plants, as we continue to transition towards increasingly sustainable energy sources to ensure the highest quality and efficiency of service while reducing emissions.

A flagship project in this area is the new SynBioS (Syngas Biological Storage) plant, one of the first power-to-gas systems in the world, capable of converting renewable electricity and wastewater into green hydrogen and then into biomethane.  

The new plant, currently under construction in Bologna Corticella within our largest wastewater treatment plant, Idar, has been designed to improve the treatment plant’s pollutant removal capacity and to make full use of surplus renewable energy by injecting biomethane into the local gas distribution network.

The power-to-gas plant will be fully integrated with the treatment of urban wastewater, enabling the conversion of renewable electricity into synthetic methane, chemically equivalent to biomethane. The facility will also feature a membrane upgrading unit for producing additional biomethane from the biogas generated by the digesters at the treatment plant. Thanks to these solutions, the Idar plant is expected to avoid around 1,450 tonnes of CO₂ emissions per year.

SynBioS: a best-practice example of circular economy and sustainable development

The plant uses wastewater and renewable electricity to produce green hydrogen and oxygen. By harnessing the CO₂ released during the digestion of wastewater treatment sludge, the hydrogen is converted into biomethane, which is then injected into the gas network and can be easily stored. In the future, the oxygen produced may also be used to boost the capacity and effectiveness of the wastewater treatment plant.

At full capacity, SynBioS will be able to produce approximately 190 Nm³/h (normal cubic metres per hour) of green gas, while avoiding around 50 Nm³/h of CO₂ emissions, the equivalent of the annual emissions of 400 cars.

“This plant represents for our Group another significant step in process integration between our state-of-the-art facilities and in industrial synergy between the electricity and urban gas distribution networks”, says Alessandro Baroncini, Networks Group Manager at Hera Group. “The power-to-gas plant and the wastewater treatment plant operate in strong symbiosis – an perfect example of fully circular design.”

It is also a leading example of circular economy in action: to produce enough methane to meet the annual needs of 1,200 households, the plant will use the wastewater generated daily by around 50 people, helping to improve the overall quality of the purification process.

In line with the UN 2030 Agenda, the construction of SynBioS represents a major step forward in tackling climate change and in delivering clean, accessible energy. And thanks to high-value partnerships – such as the one with the Italian company Pietro Fiorentini, a leading provider of products and services for the entire natural gas supply chain – we are contributing in a concrete and significant way to the achievement of global sustainable development goals.