[3] The company stated that its hybrid technology yielded several benefits, such as significant reductions in fuel consumption and emissions, around-the-clock availability, lower maintenance costs; furthermore, the locomotives' design made them suitable for working underground, such as in mines or other enclosed spaces.
According to British rail freight journalist Simon Walton, at the time of the order, demand for hybrid locomotives was booming, with Clayton having reached a three-year waiting list.
[12][13] The Class 18 locomotive features a modular design and is primarily powered by 524 kWh lead–acid batteries, the latter are reportedly rated for a lifespan of seven to eight years and are easily replaceable.
[13] Additionally, to increase its running time, the Class 18 also has an onboard 55 kW (74 hp) diesel generator, which is domestically manufactured by JCB Power Systems and is compliant with EU Stage V emissions regulations.
[7] On 1 February 2022, the first Class 18 locomotive, numbered 18001, was delivered to Whitemoor marshalling yards to begin a three-month trial with GB Railfreight, making the firm the type's first mainline operator.
[8] David Golding, GB Railfreight's Asset Director, stated of the type: "The Class 18 hybrid+ shunting locomotive has the power to play a key role in the decarbonisation of our future fleet".