A biomethane plant near Pontefract in West Yorkshire is set to meet the energy needs of around 6,000 homes, thanks to a 3km directionally drilled pipeline installed under farmland by Energy Assets Utilities (EAU).
The facility will create methane from chicken litter, food waste and organic matter produced by local farms and will purify the gas to the required specification before feeding it into the national grid. The gas will also power the site’s combined heat and power (CHP) unit, while the digester waste will be turned into nutrient-rich fertiliser.
The plant, designed by Bradford-based Aqua consultants, is due to come on stream in October and needed EAU’s utility network construction expertise to connect the biomethane site to the mains gas network. EAU worked closely with the local authority, distribution network owner, landowners and farmers to plan and install the 3km pipeline to the site, adhering to a carefully planned directional drilling schedule to minimise disruption.
As EAU’s project manager John Durkin explained, the team had to consider the potential impact of the work on local farmers and businesses. This meant drilling and laying pipe in 100m lengths, and plating over the connection pits to maintain traffic flows at key times of the day.
“We were mindful of the disruption that the pipe laying could cause and so we worked on a plan with the council and local farmers to ensure that we kept the bridleways open as much as possible. We also took account of the farm logistics – and with only one road in and out of the site, this was something we knew we had to get right.”
Despite these challenges, EAU delivered the project two weeks ahead of schedule.
Said John: “This was a great example of how good planning, close collaboration and careful project management can mitigate the impact of network construction on local people. This pipe connection will ensure this innovative facility will in time deliver sustainable low carbon energy to thousands of local homes.”
Ashley Widdop, Aqua’s Project Manager, said the digester worked by heating purpose grown crops, food waste and farmyard manures to 40oC and then processing the resulting methane using carbon and membrane filtration, before injecting propane to bring the gas up to the same specification as natural gas. There are four digester tanks on site, each capable of holding 6,800 cubic metres of feedstock.
“In some ways, the hardest part of this project was the planning phase – but network construction and plant design have gone well and the first gas-to-grid day is scheduled for October, with a gradual ramp-up to full plant production over the following three months.” said Ashley.
“It’s a very good example of sustainable energy, with the facility producing gas to feed into the grid and power the on-site CHP unit, while using digester waste to create high quality liquid and dry fertilizers for use on crops to feed the plant. It will also play a part in helping the UK meet its climate change and carbon reduction targets and, unlike wind or solar, it can operate all year round.”