There are 2 major issues that one has to take into account when considering the various Break Even point estimates from the numerous studies that are produced.
1: It hugely depends on the basis for calculating the carbon impact of generating the electricity in the first place. As this Reuters report points out, if you use the Argonne model (which is pretty widely used) you get a break even point of 13,500 miles in the USA, were there's loads of fossil generation whereas in Norway where there's loads of renewable gen, tit's more like 8,500 miles
https://www.reuters.com/business/au...e-cleaner-than-gasoline-cars-2021-06-29/Another view compares the break-even point for EVs in the US (1.5 years) against those in China (6.2 years):
https://about.bnef.com/blog/the-lifecycle-emissions-of-electric-vehicles/2. There are a fair few studies around (which tend to be sponsored by the pro-fossil lobby) which attempt a degree of legerdemain in their presentation. The most obvious is that they start with the apparently very sensible claim that to understand the true environmental impact of EVs, one has to consider the damage caused by mining the raw materials and manufacturing the batteries, together with the actual manufacture and operation of the vehicle itself including generating the power.
What these studies leave out however is the environmental impact of prospecting, drilling, extraction, transport, refining and distribution of petrol/gasoline. This is why you sometimes see the hugely inflated break even points bandied about.
Here's a proper scientific study from the University of Eindhoven which is worth reading, in which the break-even distance is calculated to be around 30,000km when comparing a Tesla 3 to a Mercedes 220D :
https://www.avere.org/wp-content/uploads/2020/09/englisch_Studie-EAuto-versus-Verbrenner_CO2.pdf
