Cursitor Doom wrote:

Anyone care to do the maths?

Assume 20 minute laptime to achieve average speed of 118mph as reported
elsewhere (spherical cows and all that) your 120kW is right assuming the
horsepower is right, so about 40 kWh per lap, allow 75% efficiency from
meter to tyre maybe, manx rates seem to be 16.75p/unit plus VAT
(presumably 5% same as here) so about £7 per fill-up ...