Severn Trent invests in trio of gas-to-grid plants
Severn Trent has invested £15M to build three biomethane plants that will turn the gas produced in the digestion of sewage sludge, energy crops from contaminated land and food waste into a gas that can be injected into the grid.
The equipment and processes are up and running at Strongford Sewage Treatment Works in Stoke and at Stoke Bardolph Sewage Treatment Works in Nottingham, with Spondon Sewage Treatment Works due to become operational when the food waste digestion plant that is currently under construction is completed next year.
Martyn Lightfoot, renewable energy development engineer at Severn Trent, explains: “This investment is all part of our programme to self-generate the equivalent of half of the energy we use by 2020.
“The biomethane process that takes place at these plants produces a renewable gas that is a fully sustainable resource and can be injected directly into the grid or use in nearby homes and businesses.
“These new plants will help us save around £3m a year on our energy bills, and that saving will be passed on to our customers who already pay less than £1 a day for their clean and waste water services.”
Severn Trent, which serves eight million people across the Midlands and into north and mid-Wales, has invested heavily in renewable energy in recent years and is now leveraging this expertise to generate both energy and income.
Each plant will produce up to 500m³ an hour of biomethane from 1,000m³ of biogas, which is roughly enough to fill up to eight hot air balloons a day, and will operate 365 days a year and 24 hours a day. The green gas generated at all three sites would be enough to heat more than 8,000 homes for a year.
The gas is made suitable for use in homes, industry or vehicles with a process which involves the gas being ‘washed’ at high pressure, ‘squashed’ so it is at the same pressure as natural gas, and then tested for quality and an odour added so it smells like normal gas.
Once that has been done, it is finally injected into the gas supply network.
Lightfoot continues: “We’ve been experts in anaerobic digestion for more than 60 years, and creating sustainable and clean energy is now a huge part of our business.
“It’s an area where we’re continuing to develop our knowledge and skills to make sure we continue to operate as a sustainable business long into the future.”
Severn Trent recently revealed it produces the equivalent of 38% of the energy it uses, and is well on its way to meeting its 50% target.
- Veolia boosts renewable generation for Southern Water Global resource management company Veolia is helping Southern Water derive more of its power from sewage through the... Read More >
- Salmon to return to River Don following sewage works upgrade The River Don is cleaner now than at any time since the Industrial Revolution, following the completion of a £78M scheme... Read More >
- SWW fined for sewage discharge into estuary Plymouth magistrates have ordered South West Water (SWW) to pay £58,375 in fines and costs for discharging sewage into a... Read More >
- Bioresource data leads to focus on sludge quality The recent publication of data about the quantity and quality of sludge produced at water company wastewater treatment... Read More >
- Automation: the key to unlock energy efficiency Huge energy savings can be made by controlling pumps and other equipment using variable speed drives and automation, writes... Read More >
- Round Table: Water companies and demand-side response The attractiveness of demand-side response as an additional income stream for water companies is clear, but utilities need... Read More >
- Opinion: Three ways for the water industry to reduce energy Water companies are hugely dependent on energy to treat water and pump it to and from their customers, costing them a lot... Read More >
- Gasification of Sludge: Innovation in Action Yorkshire Water's advanced thermal conversion (ATC) gasification plant at Lower Brighouse WWTW has achieved a timely... Read More >