More EV myth-busting…
Following up on the previous myth-busting article, this piece will synthesize the research I have read on the environmental effects of electric vehicles. The following covers the streams of thought one should engage in the environmental sphere of electric vehicles, and for the curious individual, literature sources can be found at the bottom of the page.
The life-cycle environmental effects: ICE vs Electric
Many stages are to be considered in the life-cycle of a vehicle, emissions must be considered from the production, use and disposal stages. What must be understood is the high degree of variability in the carbon intensity of electrical grids around the world. A journal article by Jack Barkenbus from the University of Texas hones in on this variability. Within the piece, emissions are measured through grams (g) of carbon dioxide (C02) per kilowatt hour (kWh). The fact is relayed from the International Energy Agency (IEA) that when EVs receive electricity with emissions exceeding 559 gC02/kWh, they are net contributors to climate change in comparison to ICE vehicles. Above is a table to compare the aforementioned figure to the carbon intensity of electricity production in European Union countries (as well as the UK).
Barkenbus highlights some of the nuances that must be considered in the environmental evaluation of EVs. C02 intensity numbers detailed are derived from averages, therefore the time in the day that electricity is generated can greatly impact emissions. Reportedly 85% of charging takes place at home, primarily overnight. Cheaper electric tariffs are offered during the night as infrastructure is used below capacity, EV owners tap into this cheap energy and fossil fuel plants are started up. To reduce fossil fuel reliance, large-scale electricity storage solutions are becoming ever-more prevalent, to avoid lapses in renewable energy availability. Residential storage solutions like the Tesla Powerwall offer a fantastic way for you to personally charge greener throughout the night, by storing the cleanest energy that you can feasibly receive.
Academics from the University of Cambridge, University of Exeter, Radboud University and the University of Macau have robustly researched, and answered, the question of whether electrification of energy end-use could increase overall emissions – in the case of electric car. This was a magnificent paper to read. Technical jargon is minimized without expense to detail, enabling anyone to absorb the crucial findings included. I highly recommend you read this paper through the link at the bottom of the page.
The paper finds that current EV models lead to lower life-cycle emissions in 53 out of 59 world regions that were included in the model used, these 53 regions account for 95% of global road transport demand. A caveat to this finding is efficient new petrol cars can cause fewer emissions than the average EV, in 2015 this happened for regions that accounted for 43% of global demand in road transport (23 out of 59 global regions included). Furthermore, and perhaps most importantly in conversation, efficient new petrol cars can cause fewer emissions than the most inefficient EVs, this occurs in 48% of the global demand for passenger road transport. However, it was stated that region-wide emission increases are likely to occur when the average emission intensity of EVs is higher than the majority of new petrol cars – this happens in just 5% of the global road transport demand (5 regions) and thus EV selection is nearly always the least emission-intensive option.
Looking into the future, the paper reports that on the current trajectory, by 2045 EVs will be on average less emission-intensive than fossil alternatives in all world regions. Bring on 2045, when without compromise to my words, I can state to my friends that EVs are on average less emission-intensive than ICE vehicles. For now, I will have to settle for the 95% figure.