California, which already accounts for 40% of all electric vehicles sold in the US and has more than 100,000 plug-in EVs on its roads, wants to have 1.5m zero emission vehicles by 2025.

State governor Jerry Brown this week signed several new bills designed to make EVs more affordable in the run up to the United Nations summit on climate change which opened in New York on today (23 September).

The legislation extends the EV rebate introduced in 2010 to encourage low income families to join the switch to EVs by giving them extra credits. So far the state has issued 75,000 EV rebates.

Other legislation paves the way to install charging stations in apartment buildings in low income areas, offers assistance for car-sharing programmes and will allow more electric vehicles to use car pool (or car sharing) lanes.

Brown said in an online statement that the legislation to increase EV use was needed "because we know in California that carbon pollution kills, it undermines our environment, and long-term, it’s an economic loser.

"We face an existential challenge with the changes in our climate. The time to act is now, the place to look is California. We’re not finished, but we sure are setting the pace."