The great electricity debate: how green is the grid, really?

In this series, we’re unpicking the true story behind electric vehicles to understand whether they are as environmentally friendly as we’ve been led to believe.?

On Tuesday, we explored the myth that lithium-ion batteries are just as bad for the environment as fossil fuels. We learned that, while lithium-ion batteries contribute to 50% of an electric vehicle’s (EV) carbon emissions, a circular approach will support a battery economy that emphasises reuse and minimises waste – further reducing an EV’s overall environmental impact.

Today, we’re looking into the electricity that powers EVs. How green is the electricity grid really, and how does this impact an EV’s green credentials?

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The big promise from EVs is that there are no tailpipe greenhouse gas (GHG) emissions, but electricity has to be generated somewhere - and it’s no secret that it is produced, in part, by burning fossil fuels.

There has been a steady increase in renewable energy generation over the past decades. In 2020, Scotland produced a record 32,063 gigawatt-hours (GWh) of renewable electricity, equivalent to around 96% of its total electricity consumption - a huge milestone for the country's journey towards net-zero. But this isn’t the end of Scotland's energy story.

Electricity generated from renewable sources in Scotland.?The drop in 2021 is likely due to milder conditions that year. Source: Scottish Energy Statistics Hub, 2022a.

Scotland produces more electricity than it uses, including a substantial amount from fossil fuels and nuclear energy. In 2020, renewables accounted for 61% of total electricity generated in Scotland, nuclear 25%, and fossil fuels 10%. Once on the grid, electricity is electricity: it is impossible to discern what is wind-generated and what is from natural gas. There is no doubt that Scotland has a hugely positive story to tell in renewables; however, there is still more work to do to ensure sustainable electricity sources across the country power EVs.?

Proportion of energy generation by fuel in 2020.?Source: Scottish Energy Statistics Hub, 2022b

A cleaner grid will be the most significant factor in reducing electric vehicle life-cycle emissions. Roughly half of the carbon cost of an EV comes from the electricity required in the battery manufacturing process - so, increased use of renewable energy and more efficient power plants equates to cleaner batteries.?

While the electricity grid is moving towards renewable sources, it is unlikely to be totally decarbonised for some time. In the meantime, some EV manufacturers are looking to distance themselves from the environmental variability of national power grids by producing their own electricity. Tesla's Gigafactory Nevada, for example, manufactures and charges 35 GWh of lithium-ion batteries per year from an onsite renewable energy source (Tesla, 2021).

Like Tesla, until the grid has a greater percentage of renewable electricity, the most environmentally-friendly way to recharge your car is to produce electricity via at-home solar panels. Of course, this is currently only accessible for a small portion of the population, with price and space issues for homeowners to consider - but it is an excellent option if you can.?

In any case, with ICEs powered by 100% fossil fuels (AA, 2022), powering your EV in Scotland currently offers a huge 60% carbon saving. As the renewable energy quantity continues to grow year on year, so too will the sustainability divide between traditional and electric cars.?

While electric cars avoid substantial emissions and carbon from being released into the environment, we haven’t yet found a way to get around the need for tyres.?

Make sure to follow @loveelectric and check back on Wednesday, October 4th as we look into what’s really going on with our tyres – or click here for the full article.