Water companies must do more to reduce process emissions from wastewater treatment sites, argued the panel of a Utility Week Live Online discussion on innovating to reach net-zero goals.
Emissions of methane and nitrous oxide from sludge and wastewater treatment have not significantly reduced in recent years and remain the biggest element of core operational carbon footprint. Howard Perry, energy manager at Severn Trent (SVT), said with no economic or policy incentives driving reductions, the onus is on water companies.
“This is not an area that we, or any other wastewater industry in the world, understands particularly well,” Perry said. He advocated proper monitoring and estimation methods to assess differences between works and operational styles, stressing: “Ten years is not a long time to crack it”.
SVT is trialling monitoring processes to recognise emissions patterns and said it is a key area for sector collaboration to get to net zero.
“Looking ahead to the next price review period it is important these areas get the investment and attention they require in order to make a serious reduction in process emissions,” Perry said.
Speaking alongside Perry were Lutz Johnen, managing director of Aquility and Wessex Water’s head of renewable energy Dan Green who discussed the likelihood of the sector achieving its 2030 ambition.
Green said emerging technologies and growing understanding were improving the picture each year.
“We will be in a much better place in terms of our knowledge in the future,” he explained. “I’m not expecting some technological saviour in five years’ time, we have to look at what is credible and possible now.”
Perry said under the current definition of operational carbon footprint, the sector will get to net zero by 2030 but questioned how credibly it could be done and how much offsetting would be necessary.
He said wider economic changes, such as the electricity grid decarbonising rapidly, will make a difference. But he added that a net-zero supply chain was not possible in the next decade.
Green believes the biggest challenge is the capacity within each of the water companies to accommodate the agenda alongside the day to day business of providing an essential service. He described it as a “huge challenge organisationally”.
Johnen echoed sentiments that policy changes would accelerate innovation and added all companies are part of a jigsaw to reach the solution.
Johnen added that decarbonisation at localised levels in-home and in water reuse was an equally essential part of that jigsaw.