MAN Diesel & Turbo has delivered, installed and handed over a genset of the type MAN 20V35/44G to Wykes Engineering in Rushden, England. The engine generates up to 10.4 MW of electrical power from biogas at the power plant, under a contract that was completed in just eight months. It supplements an existing 7L51/60DF engine that has been running on biogas at the power plant since 2014. The plant is used to back up the base load supply in the local electricity grid and now has a capacity of around 17 MW.

In Rushden, Wykes uses food waste such as waste from meat products, fruit juice, and dairy products deemed not fit for human consumption. This mixture decomposes in the fermenter, producing biogas, which is utilised to fuel both the existing engine and the new unit.

“The energy market in the UK is particularly interesting for us, as power supplies and demand are subject to great volatility as a result of the decision to phase out coal, and this is having a direct effect on energy prices,” commented Hajo Hoops, senior sales manager Gas Power Plants at MAN D&T: “Furthermore, Brexit will also mean largely autonomous power supplies. That will make it extremely exciting … in the years ahead.”

The energy system in the UK also includes a capacity market, which pays generators to guarantee reliable supplies even at load peaks. This creates incentives for new investment, in particular for supporting renewables.

Biogas plants as typically encountered in Europe using agricultural products are usually operated with smaller, less efficient engines with outputs up to 1MW. Gas from food waste can power a larger engine and a downstream steam turbine process, allowing an efficiency close to 50%. Hajo Hoops again: “The installation of the first engine with output around seven MW has already been a success. By expanding the power plant MAN D&T are demonstrating that the efficient use of biogas is also possible in the order of ten MW or more”.