The evolution of benchmaking the carbon efficiency drinking water companies in England and Wales

Water utilities face the challenge of transitioning to a low-carbon urban water cycle while reducing operational costs. This study evaluates the static and dynamic carbon efficiency of a sample of water companies from 2013 to 2018 operating in England and Wales. Each company was evaluated relative to itself and its peers using cross-efficiency Data Envelopment Analysis techniques. The results showed that the carbon performance of the water industry improved by 2.1% per year, mainly due to efficiency change. In contrast, the contribution of factors driving technical and scale change was almost negligible. • Energy-water-carbon nexus of water utilities was evaluated. • English and Welsh water companies have improved its carbon performance across years. • Cross efficiency techniques were used to assess dynamic carbon performance.