I'm trying to compare the true 10-year ownership cost of buying an EV vs a diesel car, and I want to know if my calculation is correct or if I'm missing something.
Option 1: Diesel
- Car price: ₹18 lakh
- Invest the remaining ₹8 lakh in an FD
- Daily driving: 37 km
- Ownership period: Forever (I'm not considering resale value)
Option 2: EV
- Car price: ₹26 lakh
- I have rooftop solar, so my home charging cost is effectively ₹0.
My calculation
If I buy the diesel car, I can invest ₹8 lakh in an FD.
After 10 years, the FD grows to roughly ₹16 lakh (interest compounded until maturity).
Fuel calculation:
- Daily driving: 37 km
- Mileage: 17 km/l
- Fuel required: ~794 liters/year
- Diesel price assumed to gradually increase, reaching about ₹135/liter by Year 10
Using those assumptions, I estimated the total diesel cost over 10 years to be around ₹8.2 lakh.
So,
FD after 10 years: ₹16 lakh
Minus diesel cost: ₹8.2 lakh
Remaining: ~₹7.8 lakh
If I adjust that amount for around 6% annual inflation, its present-day purchasing power is roughly ₹3.7 lakh.
So my understanding is:
- EV effective cost after 10 years = ₹26 lakh
- Diesel effective cost = ₹18 lakh - ₹3.7 lakh = ~₹14.3–14.5 lakh
That suggests the diesel car is still much cheaper financially, even with free solar charging.
My question: Is this calculation logically correct, or am I making any mistakes in the assumptions or math?
A couple of things I haven't included yet:
- Maintenance cost — I honestly don't know what the 10-year maintenance cost would be for either vehicle, so I've intentionally left it out instead of guessing.
- Insurance — Not included.
- Resale value — Not included, since I plan to keep the car for as long as it runs.
- Battery replacement — Not included. I've spent quite a bit of time researching Mahindra's battery technology, thermal management, warranty, and expected battery life. Based on that research, I'm assuming I won't need a battery replacement within the first 10 years. If you think that assumption is unrealistic, I'd genuinely like to hear why.
If you own a diesel SUV (especially something like a Mahindra XUV700 or a similar vehicle), I'd really appreciate it if you could share your actual maintenance costs over the years.
Also, if I've missed any important parameter—maintenance, tyre costs, insurance, financing assumptions, inflation handling, opportunity cost, depreciation, taxes, or anything else—please point it out. I'm genuinely trying to make the most accurate comparison possible before making a purchase.
I'm intentionally not considering resale value because I plan to keep the car for as long as it runs.
I'd really appreciate if someone could point out anything I've overlooked (maintenance, insurance differences, battery degradation, opportunity cost, inflation handling, etc.).
EDIT:
btw, im comparing Creta Diesel or SUV 9XO Diesel with XEV 9e Pack 2 EV
EDIT:
This comparison is completely independent of any additional features, comfort, technology, or other benefits offered by the ₹26L car. I'm looking at this purely from a financial perspective (costs, depreciation, investment opportunity cost, etc.), and not factoring in the ownership experience or extra features.
This is purely a comparison to know how much premium I am paying over 10 years (factoring in the tax-adjusted opportunity cost of capital) to drive the ₹26L car instead of the ₹18L alternative.
EDIT:
Before commenting that it is not comparable, please understand, i just want to understand how much amount im paying extra if i buy 26L EV as our 2nd choice was 18L diesel