Carbon emissions connected to electric vehicles have been driven down in recent years by the drastic decline of coal generation and the rapid growth of renewables.
Some EV models are now responsible for less than half the emissions of the cleanest conventional or hybrid equivalent when driven, according to the latest Electric Insights report produced by researchers at Imperial College London in collaboration with Drax.
The analysis found that emissions from the power sector fell to less than 200 grams of carbon dioxide per kilowatt hour (gCO2/kWh) over the three months to the end of June – a ten per cent drop on the previous quarterly record.
Sunny skies and strong winds meant the carbon intensity of the power sector reached all-time low of 71gCO2/kWh on Sunday 11 June.
The Tesla Model S – one of the most power hungry electric cars – would have effectively emitted 124 grams of carbon dioxide per kilometre (gCO2/km) when driven back in 2012 – putting it on par with a 180 horsepower Land Rover. It now has a carbon impact of just 74gCO2/km during winter and 41gCO2/km during summer.
In 2016, the year-round emissions of the Model S dropped below those of the cleanest conventional or hybrid alternative – the Toyota Prius (74gCO2/km). The most efficient all-electric models – including the Nissan Leaf and the BMW i3 – passed the threshold several years earlier and currently produce less than half the emissions of the Prius.
Iain Staffell from Imperial College London told Utility Week: “Every time there was a story about electric cars, or when the government said they were going to scrap diesel and petrol by 2040, you’d always hear the commentators saying: ‘Ah, but, they’re not so good when you think about the emissions of the power generation’.
“Actually, with what we’ve managed to do with displacing coal and expanding renewables, it is now definite that electric vehicles are lower carbon that anything else we’ve got available to buy today.”
Staffell said emissions from electricity generation have been falling steadily by around 60gC02/KWh year on year since 2013 but, with the average load factor for the remaining coal plants in the UK down to just four per cent over the last quarter, progress will soon begin to slow.
“We will soon hit the point where emission will level off,” he added, “and there will be much slower reductions because you’re no longer switching from coal to gas. It’s only going to be switching from gas to low-carbon sources from then on.”
He said the power sector could hit this plateau as early as 2020 if the government decides to keep the carbon price floor in place.
Electric vehicle carbon intensity
Source: Electric Insights, Imperial College London and Drax