Esholt Sewage Treatment Works is one of Yorkshire Water’s biggest sewage treatment works serving around 760,000 people in Bradford and Leeds, and processing over 30,000 tonnes of sludge. It is Yorkshire Water’s second largest waste water treatment plant, exceeded only by Knostrop in Leeds.
Seeing the potential for additional combined heat and power (CHP) efficiency from advanced anaerobic digestion, Yorkshire Water appointed Morgan Sindall and Grontmij as its large scheme delivery partners who formed a Joint Venture to implement these changes.
Edina tendered for the provision of the supply and installation of the CHP and was successful in obtaining orders for two MWM manufactured TCG 2020 V16 reciprocating gas engines. With an output of 1.56MWe each, the MWM TCG 2020 is an engine range renowned for its efficiency and longevity, and is capable of operating on biogas.
The biogas produced from the breakdown of sewage sludge as part of the anaerobic digestion process produces renewable electricity and heat through CHP application. The biogas is combusted in the MWM gas engines and the electricity, and heat is recovered to power the sites infrastructure.
The 3.2MWe biogas CHP plant was containerised within a weatherproofed attenuated enclosure at Edina’s manufacturing plant based in Lisburn, Northern Ireland and delivered to site in modular form, expediting the site installation.
The two MWM engines formed part of a new energy centre onsite which would necessitate the relocation of the two existing CHP units which was also part of Edina’s scope of supply.
To maintain power at site, the 3.2MWe CHP had to be operational before the disconnection of the existing CHP units in order to provide consistency of service and no loss of revenue to the operator.
In November 2013, the original CHP units were re-connected in their new situation forming part of an integrated energy centre which can generate over 4MWe.
The CHP facility will provide power and heat for the 750-acre Esholt site and reduce Yorkshire Water’s annual energy bill by £1.3million, and cut their carbon footprint by 9,000 tonnes.
The process also creates a total of 62,000 tonnes of fertiliser each year which is recycled back into Yorkshire’s agriculture.
2 x 1.56MWe TCG 2020 V16