SolarToolsHow This Tool Works
The EV Total Cost of Ownership (TCO) Calculator goes beyond simple fuel savings to show the true 5-year cost of owning an EV versus a comparable petrol car. Most EV comparisons only look at fuel — but the real picture includes purchase price (after tax credit), depreciation, insurance, maintenance, and financing. This calculator accounts for all of it.
The headline number is the total cost difference over your ownership period. A positive number means the EV saves money; a negative number means the petrol car is cheaper. The breakdown shows exactly where the EV wins (fuel, maintenance) and where it loses (purchase price, depreciation, insurance).
EVs typically win on fuel ($600/year vs $1,500/year) and maintenance ($400/year vs $700/year), but lose on purchase price (higher upfront even after credit) and depreciation (45% vs 35% over 5 years). Insurance is also $200–400/year higher for EVs due to repair costs. The net result depends on your annual mileage, local electricity/gas prices, and how long you keep the car.
- EV purchase price — MSRP before any incentives. Tesla Model 3: $42k, Model Y: $50k, Ioniq 5: $45k.
- EV federal tax credit — $7,500 for qualifying EVs. Check IRS list. Some states add $2,000–$5,000.
- EV efficiency — real-world mi/kWh. Sedans: 3.5–4.0. SUVs: 2.8–3.3. Trucks: 2.0–2.5. Drop 10% from EPA rating.
- EV depreciation — EVs lose 40–50% over 5 years (faster than petrol). Teslas hold value better than most.
- Petrol comparison — pick a car in the same class (Camry vs Model 3, RAV4 vs Model Y).
- Insurance — get quotes for both. EVs typically cost $200–400/year more.
The calculator assumes home charging at your electricity rate. If you rely on public DCFC ($0.40–0.60/kWh), the EV fuel advantage disappears — enter a blended rate.
When to Use This Calculator
Why EVs depreciate faster
EVs lose value faster than petrol cars in the first 3 years for three reasons: battery technology improves rapidly (a 2022 EV looks obsolete next to a 2025 model), federal tax credits reduce the effective new-car price (so used buyers expect similar discounts), and battery warranty anxiety (buyers worry about out-of-warranty battery replacement costs). By year 5, depreciation rates converge.
The maintenance advantage is real
EVs have no oil changes ($80/yr), no transmission fluid ($200/3yr), no spark plugs ($150/4yr), no exhaust system, and regenerative braking extends brake pad life to 100k+ miles. Independent studies (Consumer Reports, AAA) put EV maintenance at roughly half the cost of petrol: ~$0.06/mi vs $0.10/mi. Over 13k miles/year, that's $520/year in savings.
Insurance is the hidden cost
EVs cost 15–25% more to insure than comparable petrol cars. Reasons: higher repair costs (aluminum bodywork, specialized shops), battery damage totaling the car after minor accidents, and limited used parts supply. Get insurance quotes before buying — the difference can be $300–$600/year, which over 5 years adds $1,500–$3,000 to EV ownership costs.
When the EV wins
EVs win on TCO when: (1) you drive 15,000+ miles/year (more miles = more fuel savings), (2) electricity is cheap relative to gas (Pacific Northwest, Texas), (3) you keep the car 7+ years (depreciation advantage shrinks over time), and (4) you qualify for the full $7,500 federal credit. If any of these are false, run the numbers carefully.
When petrol still wins
Petrol wins when: (1) you drive under 8,000 miles/year, (2) you don't qualify for the federal credit (income too high or EV not on qualifying list), (3) electricity is expensive (Hawaii, California at $0.30+/kWh), or (4) you trade cars every 3 years (depreciation kills the EV case).
Frequently Asked Questions
Usually yes, but not always. Over 5 years, EVs typically save $3,000–$8,000 in fuel and maintenance but lose $2,000–$5,000 on depreciation and insurance. Net savings: $1,000–$6,000 for high-mileage drivers in cheap-electricity regions. Low-mileage drivers may find petrol cheaper.
EVs cost 15–25% more to insure — typically $200–$400/year extra. Over 5 years that's $1,000–$2,000. Get quotes before buying, as rates vary significantly by model and insurer.
Three reasons: rapid battery technology improvement makes older EVs seem obsolete, federal tax credits reduce effective new-car prices (so used buyers expect discounts), and battery warranty anxiety. By year 7, depreciation rates converge with petrol cars.
No — add $1,200 for a Level 2 home charger installation to the EV purchase price if you don't already have a 240V circuit. Use the Public DC fast charging at $0.40–0.60/kWh wipes out most EV fuel savings. If you can't install home charging, enter a blended electricity rate (e.g., $0.35/kWh if half your charging is public) or reconsider whether an EV makes sense for your situation.
Leasing an EV can be attractive because the manufacturer absorbs depreciation risk and you may qualify for the $7,500 credit even if you wouldn't on a purchase (lease credits pass through to the manufacturer, who often discounts the lease). Run both scenarios — leasing often wins on EVs due to depreciation uncertainty.
Further Reading
Deep-dive articles and guides related to this calculator.
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