Energy use and renewable energy
Water industry operations are relatively intensive, requiring large amounts of energy for pumping, water treatment and waste management. Wastewater processes use about half of the total operational energy.
Greenhouse gas emissions from the operational side of the water industry are around 0.7% of UK emissions (Ofwat, 2010). In 2011-12 companies reported that they emitted the equivalent of about 4 million tonnes of carbon dioxide. This was 6% lower than the previous year (Ofwat).
Although the overall trend in total energy use continues to rise, to comply with tougher environmental standards and to serve more people in our growing population, the amount of renewable energy generated by companies is also increasing.
Increases in renewables
The higher amounts of renewable energy generated by companies are achieved mainly through significant investment in Combined Heat and Power (CHP) and in generating biogas from the anaerobic digestion of sludge, a solid by-product of the sewage treatment process.
Other contributions include energy from hydro, solar and wind, and imported renewable energy. In 2010-11 around 10% of all the energy used by the water industry came from its own renewable sources; Ofwat analysed company business plans and predicted an increase of 30% on this volume by 2015 (Ofwat, 2010).
Many water companies have decided to increase renewable energy generation to offset the impacts of increased energy prices, to use their resources (e.g. sludge) as efficiently as possible, and to increase revenue (e.g. through the sale of Renewable Obligation Certificates, which generate a premium on renewable electricity sold).
The water industry is therefore making a substantial contribution to the government requirement of 15% renewable energy by 2020, within an EU target of 20% by 2020. The industry is committed to and will continue to explore opportunities to use its resources as efficiently as possible.
Carbon reduction potential
The industry is a significant user of energy, and the links between greenhouse gas emissions and distribution, treatment and consumption is increasingly being understood.
The industry is part of the Carbon Reduction Commitment (CRC) Energy Efficiency Scheme and has considerable potential for renewable energy generation.
The amount of energy used by the water industry has increased despite efforts to keep use in check and the introduction of the CRC scheme.
There is a tension between the benefits from increased quality standards, which sometimes have questionable environmental benefits, and the financial and environmental costs of additional energy-intensive treatment processes.