There has to be an exceptionally good reason for me to be anywhere but under the duvet at 7.00am on a Saturday morning, but the Brighton-to-London Future cars run was one of the few.

I was offered the chance to drive Mercedes’ fuel-cell powered B-Class F-Cell on the 57-mile run from the south coast to Pall Mall in central London. The Merc was one of 64 alternatively fuelled cars on the run, a spread of vehicles that ran from production models such as the Golf BlueMotion and Focus Econetic, to Tesla roadsters, electric taxis, Gordon Murray’s tiny T.25, Nissan’s Leaf and Tata’s battery-powered Indica.

I’ve driven the B-Class F-Cell before, but there’s no need to get used to it, because it barely differs from the production B-Class. Just slot the gearlever and we were off. The rev counter has been replaced by a meter which shows both fuel use and energy recovery. So the key was to keep the needle as close to zero as possible, and get it to swing down into energy recovery as often as possible.