The ‘Net Zero Hub’, led by Severn Trent Water and based at Strongford, Stoke-on-Trent, will deploy cutting-edge technology, including Siemens gPROMS digital twin, to reduce and remove CO2, CH4, and N2O emissions, which account for 57% of all emissions from the wastewater treatment process.

 Photo: Severn Trent's Strongford Wastewater Treatment Works 

The ground-breaking project – which is backed by all UK and Irish water companies and international Net Zero Partnership with Aarhus Vand in Denmark and Melbourne Water in Australia – will transform Severn Trent’s large, carbon intensive Strongford wastewater treatment plant into the world’s first retro-fit carbon neutral site.

The new ‘Net Zero Hub’ won £10 million funding from the Ofwat Innovation Fund, a further £0.9 million has been secured through Horizon Europe and £28 million will be invested by Severn Trent to make this ambition a reality.

The partnership of water companies and industry providers is set to remove direct process emissions from the bacterial digestion of wastewater for the first time. The work is set for completion in 2024 and represents a world first, providing a blueprint for net-zero wastewater treatment. 

The gPROMS technology will model the water treatment process in real time through 60,000 dynamic and static data points and will enable the operator to closely monitor energy use and emissions, while ensuring it can keep within permit conditions for effluent quality.

The digital twin will also help create the first mechanistic model of N2O, which is 300 times more potent as a greenhouse gas than CO2.

The Siemens technology, originally spun-out of Imperial College London (UK) for the pharmaceutical and petrochemical industries, is an example of how innovation developed for other sectors is being transferred into the water industry to make a transformative impact.

Siemens is working alongside Atkins, Explore AI and Xylem on the digital twin workstream.

Rich Walwyn, Head of Asset Intelligence and Innovation at Severn Trent, said:

“While combating the climate emergency is a huge challenge, it is one we are determined to meet, and collaborating with industry experts and water companies – be it here in the UK or overseas – is key to bringing about change.

“We have scoured the world to find the best solutions to measure and then remove, reduce, replace and offset operational emissions, with the goal of integrating them all at our new ‘Net Zero Hub’. This innovative project is incredibly exciting for the sector, as it has the potential to change the face of wastewater treatment worldwide.”

Adam Cartwright, Head of IoT Applications at Siemens UK & Ireland, commented:

“Projects like the Net Zero Hub will be viewed in the future as the beginning of a change in how the water industry approached technology and industry collaboration.

“Digitalisation means that operational silos can be linked so that a whole system can be optimised to meet major challenges like achieving net zero, and the sector must embrace this to deliver the change it needs.

“But we must recognise that those challenges are so large and complex that no-one company can solve them. This project is an excellent example of the depth of collaboration needed to make investment stretch further, while uncovering new ways of how the industry can deliver infrastructure differently.”