A prototype, known as "the farm cart" was built which showed promise, accelerating from a standstill to 30 mph (48 km/h) in ten seconds, giving a top speed of 36 mph (58 km/h) and a range of 18 miles (29 km) in urban conditions. In July 1965 negotiations took place between the Scottish Aviation and the Central Electricity Generating Board aimed at marketing the car through the area electricity boards' regional showrooms. The prototype was further developed with the addition of wood and aluminium bodywork and it was then registered for use on the road. It was successfully demonstrated in London and Bristol and received a great deal of publicity when on one occasion it was driven by the racing driver Stirling Moss. A further 12 cars were built for testing and the first of these went on show at the Ideal Home Exhibition in February 1967.
The project began to run into difficulties because of an inability to resolve the uneconomic battery life of the Lucas Industries batteries available at the time. It was cancelled when major weaknesses in the car design were revealed by testing at the Motor Industry Research Association test track, subjected to the same tests as a conventional car, the suspension eventually broke and the car was claimed to be unroadworthy.