High Quality Content by WIKIPEDIA articles! The British Rail Class 90 electric locomotives were built by BREL at Crewe from 1987-1990. Each locomotive weighs 84.5 tonnes and has a top speed of 110 mph (180 km/h). They operate from 25 kV AC overhead wires and produce 5,000 bhp (3,700 kW). The class is employed on both express passenger services and heavy freight trains.