Renewable energy generation

We are trying to improve our generation of renewable energy.

There are a number of reasons, including the increasing volatility of energy process, our wish to see year on year reductions in our carbon footprint and the government’s Carbon Reduction Commitment which is focused entirely on energy use.

As a result of restrictions on the availability of agricultural land for treated sludge, we are building an improved sludge treatment plant at our largest sewage treatment works in Bristol. This will provide enhanced sludge treatment.

The first stage of acid phase digestion (APD) is now in operation and has increased the production of methane gas so that we now generate more renewable power from the site.

Over the last year the increased focus on the optimisation of digesters and maximisation of biogas production has had great benefits for our renewable energy production.

This has been helped in part by our creation of GENeco, our waste to energy business, which operates our Bristol STW and Berry Hill sludge treatment centre.

Bristol STW has moved beyond self sufficiency for electricity and is now a net exporter to the national grid.

Outside the regulated business, we have continued our work on:

• possible investment in food waste digestion in Bristol
• potential wind turbine installation at Bristol STW, which we estimate could generate a total of 20GWh each year from four proposed turbines
• investigating other smaller projects, eg, hydropower and other sites suitable for medium or large wind energy generation.