Zac Goldsmith’s election campaign ran out of steam, or renewable energy at least, in Richmond Park recently, when part of his green fleet ran out of juice.

The environmentally-friendly fleet of electric bikes were introduced to boost his election campaign, but Ben Mallet, of Richmond Park and North Kingston Conservative Future, discovered a downside to campaigning the green way - when he was left to walk one through the park on foot.

Thankfully a passerby used his own modern technology to film Mr Mallet when he had to resort to pushing the machine, and posted it on YouTube for all to see.

Mr Goldsmith, Conservative parliamentary candidate for Richmond Park and north Kingston, previously said: “They cost 2p per mile, they can take passengers, carry leaflets and they are surprisingly fast. Everyone enjoys riding them.”

However, they are surprisingly slow when you are left to walk them, with cars whizzing past.”

Despite the blunder, Mr Goldsmith stood by the four electric tricycles, which are emblazoned with “I back Zac”.

He said: “That’s the cost of an electric vehicle I suppose. But they’re cheap and fun, and allow us to be in many places at the same time.”

Mr Mallet said: “I wasn’t really the YouTube debut I was hoping for. I completely underestimated the length of the journey and thought that I would take the risk.

“Those bikes are incredible though - they’re really good for transporting leaflets and posters around and they’re really eco-friendly.

"We’ve saved a lot of car journeys using them and I think our carbon footprint is considerably lower as a result.”