The environmental impact of EVs is generally quantified by identifying their "lifecycle emissions" which include manufacturing of the vehicle, powering the vehicle through its life, and finally decommissioning it. What this bitesize review will focus on is the powering aspect of EVs and comparing two different models: the United Kingdom and China. EVs by definition are powered by electricity and not burning fuels like normal internal combustion engine (ICE) vehicles and therefore do not physically emit any greenhouse gases (GHG). However, if the production of this electricity is generating significant GHG emission through the burning of fossil fuels, this can have an impact on the "green" aspect of the vehicle.

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The main fuel sources to generate the electricity which powers EVs are coal, oil, gas, nuclear and renewable. Coal-fired powerplants are known to release more GHG per unit of energy produced than any other of these fuels, therefore the percentage contribution of coal-fired powerplant in electricity production impacts the "green" level the EV can achieve.

The power grid in the UK for example generates its electricity mainly from combustion of natural gas, accounting for approximately 40% of the UK's total electricity produced, while coal makes up a significantly smaller proportion of the total (approximately 3%), and renewables are increasing gradually and make up approximately 30%. This agrees with the UK's target of decarbonising the grid by the phaseout of coal-fired powerplants by 2024, which will be an important topic discussed at COP26. So, according to this it has been calculated that EVs in the UK produce around 75 grams of carbon dioxide (CO2) emissions per mile.

In contrast to this, China is a country that relies heavily on coal-fired powerplant to generate its electricity, accounting for approximately 60% of the country's total output. This translates to around 190 grams of CO2 per mile travelled by a Chinese EV. So, being the world's second biggest economic power, the decarbonisation of the Chinese grid could have big impacts for global GHG emissions by EVs. However, this is easier said than done as the country requires regular energy supply and changing to less emitting fuels for their energy generation is proving to be difficult and causing problems country wide.

That being said, both UK and Chinese EVs have lower CO2 per mile emissions compared to traditional ICE vehicles, with these reaching 250 grams of CO2 emitted per mile. With the amount of EVs sold globally on the rise, and decarbonisation of power grids becoming a key point of discussion in COP26, it is safe to say that the future of EVs is assured and prosperous. However, are EVs the solution to climate change? The short answer is NO, there is no single answer to this issue, but by investing in this and continuing to set ambitious targets, EVs can become an important pawn in the fight against climate change.