For Raghunandan Yadav the day starts, as it does for many of us, with a glance at his phone. The passenger requests are already coming in. By 6am, he sits in his shiny white and blue autorickshaw parked outside his home in Lucknow, northern India, and selects a customer from his Uber app.

For decades, this is how people across Asia have got around, crammed into the back of tiny three-wheeled vehicles, nicknamed “tuk-tuks” because of the noise from their engines.

But a revolution is under way: Indian autorickshaws are going electric. Yadav’s vehicle, a £2,500 Mahindra Treo that he drives until 10pm each night, is powered by a battery under the seat, charged overnight through a standard three-pin electrical socket in his home.

“The passengers much prefer it,” said Yadav, a 36-year-old father of two. “There is no pollution.”

The global revolution in electric vehicles is being accelerated not by the £60,000 Teslas in London and Los Angeles but by these autorickshaws on the streets of Lucknow and other Indian cities.

The scale and speed of this shift, and the potential impact on health and the climate, is what excites environmentalists. Two and three-wheelers make up more than 75 per cent of the vehicles on Indian roads and the fossil-fuelled varieties generate up to 50 per cent of the traffic smog that chokes the air in its megacities. This switch to clean technology, arguably one of the biggest and most significant environmental transitions in the world, has now received royal approval.