From manufacture to lifetime emissions, just how green are EVs compared to petrol or diesel cars?

Carmakers are pledging billions to develop new battery electric vehicles (BEVs) with the expectation that more than 30 million of them will be on European roads by 2030.

Electric cars may generate no tailpipe emissions but the manufacture of the vehicles and batteries do still contribute to carbon emissions. 

So, just how clean are BEVs, and how do they stack up against traditional internal combustion engine (ICE) cars that run on petrol or diesel?

Life cycle emissions are those created by the production, use, and disposal of a product; so for an electric car, everything from the raw materials, and the battery power sources to the recycling and reuse of the vehicle at the end of life must be accounted for.

The extraction, refinement, transportation, and manufacture of lithium-ion batteries is a very energy-intensive process which means that emissions are higher in the production phase of battery electric cars compared to an ICE car.

While the manufacturing process for ICE cars may not be as high, it still has a significant carbon footprint.

Reuters reported earlier in the year that Volkswagen and Toyota were aiming to be carbon neutral by 2050, while Hyundai Motor Group said Hyundai Motor and Kia were "accelerating efforts" to become carbon neutral.

All new vehicles from Mercedes-Benz will be net carbon-neutral along the entire value chain by 2039 and General Motors (GM) plans to be carbon-neutral by 2040 in its global products and operations.

In contrast, Swedish company Polestar ambitiously aims to produce a net-zero car by 2030 by identifying and eliminating all carbon emissions, from the extraction of raw materials to production through to end-of-life handling.

The carbon gap between BEV and ICE cars may be significant when a