AN ELECTRICIAN has invented a device which sets off an alarm in his van to help him save more than £100-a-month in petrol.

John Diamond, 50, of Darlington, explained that a buzzer goes off in his van to stop him driving too fast or braking too hard.

The canny inventor did not wish to reveal exactly how the device works “in case I decide to go on Dragons’ Den” but said he was now getting about 300 miles per tank of petrol compared to 240 previously.

Mr Diamond, a selfemployed electrician who lives in Darlington but works across County Durham and into North Yorkshire, said he had found himself paying more than £100-a-week in petrol but that is now down to about £80.

He had originally hooked his van up to a house alarm claxon but opted to buy a quieter buzzer after it sounded while he was giving the 74- year-old mother of his girlfriend a lift, and gave her an unintentional shock.

He said: “Initially, when I built a prototype I borrowed a claxon from an alarm system.

However, I gave an elderly relative, complete with pacemaker, a lift home, forgetting to tell her and the result was nearly disastrous. I use something more subtle now.”

Mr Diamond, a father-ofthree, said that his van had passed its MoT with the buzzer and that very expensive “super cars” are also often fitted with car safety and energy efficiency warning devices.

He said: “It’s an educational thing. The idea is not to drive too fast and consequently not to brake too hard.

“It really works. I had it in the car for a few weeks and it changed my behaviour. Every few weeks I switch it back on just to keep my new skills brushed up.

“It teaches you to drive more smoothly, not racing between red lights and roundabouts and you have to learn to anticipate other road users much better to avoid braking and accelerating abruptly.

“It costs next to nothing and can be installed by anyone competent in a matter of minutes.”

He added: “Of course I realise nobody needs a buzzer to drive more efficiently. It merely acts as a reminder.”