What your spreadsheet shows is that, when the cost of the petrol car (ICE) and the electric vehicle (EV) are almost the same, the depreciation will also be similar. Therefore, in these circumstances, it’s most likely that the cost of owning the EV will be less than that of the ICE, because of savings on fuel costs.
But, in my example, where the cost of the NZ-New Kona 64 kWh EV ($82,000) is $40,000 more than the cost of the equivalent ICE Kona ($42,000), then the extra depreciation (over a 3-year period) on the EV of nearly $17,000 is likely to be at least double the amount of fuel savings from owning the EV over that period.
Just one other point about your spreadsheet, I notice that the average electricity costs that you factored in over the 5-year period are 19 cents per kWh. However, if you buy an expensive long-range EV, it’s possible that quite a lot of your charging may be at a fast ChargeNet DC charger. So, instead of paying 19 cents per kWh, you could expect to pay up to 62 cents per kWh when you are charging your EV away from home. If this is factored in to your spreadsheet, the fuel savings from owning the EV might not be as large as stated, particularly when you often use fast DC charging.
Yes No Maybe? As several variables can effect the outcome as you have noted - including:
- Cost of fuel vs cost of power - ie. which will increase more?
- Average distance travelled?
- Where you charge? A Chargenet charger VS. At home at night? (Which is what I would be doing 95% of the time - so my power cost is correct for my use case.)
- Home PV and Batteries? And what happens to the economics when household PV and battery storage becomes common and charging is "free"? (I appreciate their is a capex cost of install - but this is reducing as well.)
- Resale Value - FYI - depreciation I treated more as resale value - not the usual tax definition. So as a result I don't believe they will be the same rate for all vehicles - as resale varies significantly between different vehicles depending on the buyers perception of value. And I fully expect within a decade or 2 ICE resale values will crash as they become less attractive and EV's resale will hold in comparison.
Hence why the original sheet maker would have made all of these fields are changeable.
So yeah for some cases EV's won't stack up - and for some, like mine ($70k car's - doing 500km/week - charged at home - with different resale values) - they will.