Petrol to electric: the real numbers, four months in

Motoring • Published 7 August 2026 • 8 min read • By UKCostOfLiving.org

In April, with petrol edging over 150p a litre after the Iran conflict began, I did the sums on switching to electric. Four months and several thousand miles later, here are the real numbers — including the one circumstance where I'd tell you not to bother.

Fuel prices follow a pattern traders call "up like a rocket, down like a feather". When oil spikes, pump prices jump within days; when oil falls, they drift down over months, if they fully come down at all. April's spike has mostly stuck: the UK average is around 160p a litre as of August — higher than when I switched. Whatever happens next in the oil market, betting on a return to 130p petrol feels like wishful thinking.

I do roughly 15,000 miles a year, which is the single most important number in this article. Everything that follows scales with mileage — and that cuts both ways.

The core numbers: pence per mile

My previous petrol car managed about 45mpg in real-world driving. My replacement is a second-hand Tesla Model Y Long Range, which does about 3.4 miles per kWh in mixed UK driving. That gives three very different costs per mile depending on where the electricity comes from:

Read that table carefully, because it contains both the case for switching and the case against.

I'm on EDF's overnight EV tariff, which gives me 8p/kWh between midnight and 6am — the car simply schedules itself to charge in that window. Charging that way, I've cut my fuel cost from roughly £2,400 a year to under £400 — a saving of around £2,000 a year at my mileage. Several suppliers offer similar overnight EV rates, typically 7–9p/kWh in a fixed early-hours window. Even without one, charging at the standard capped rate roughly halves the cost of petrol.

But look at the last row. Rely on public rapid chargers and electricity costs more per mile than petrol. This is the number most EV-savings calculators quietly leave out, and it's why the driveway question matters more than any other.

The costs beyond fuel

Servicing and maintenance. My old petrol car was due its cam belt change — a few hundred pounds every five years — on top of annual servicing, oil, filters, and the usual wear items of a combustion engine. Four months in, the Tesla has needed nothing (touch wood). An EV drivetrain has a fraction of the moving parts, there's no oil to change, and one-pedal driving means the brakes barely wear because the motor does most of the slowing. I'm not claiming EVs never go wrong — but the routine maintenance burden is clearly lighter.

Tyres. The honest counterpoint: EVs are heavy and instant torque is hard on rubber. Expect tyres to wear somewhat faster than an equivalent petrol car. It doesn't come close to offsetting the fuel saving, but it's real.

Road tax. EVs no longer escape VED — that advantage ended in April 2025. Budget for it like any other car.

Insurance. EV premiums often run higher than petrol equivalents, partly due to repair costs. Get a quote before you commit, not after.

The car itself. This is where "but a new EV costs £50,000" objections usually start — and it's why I bought second-hand. Used EV prices fell hard over 2023–25, which was bad news for first owners and very good news for second ones. The steepest depreciation had already happened before I arrived. Factoring in the change of car, at 15,000 miles a year the fuel and maintenance savings still made the move clearly worthwhile for me. At 5,000 miles a year, the same sums would look much less convincing — a £700-a-year fuel saving takes a long time to justify changing a car you'd otherwise keep.

Living with it

The finance was the reason, but the day-to-day has been better than expected. One-pedal driving is genuinely relaxing once it clicks — you stop touching the brake in normal traffic. The ride is smoother and quieter than any combustion car I've owned. Charging at home means starting every day "full"; for a 15,000-mile year, I visit public chargers only on long trips.

What do I miss? The sound of a good engine, honestly. And the involvement of a manual gearbox — an EV is quick but it isn't exciting in the same way. If driving is your hobby, that trade-off is real. If driving is how you get to work, you won't think about it after week two.

As for the myths — range anxiety, batteries dying at 100,000 miles, EVs constantly catching fire — my experience so far is that they're mostly overhyped. The Model Y's real-world range covers my week without thought, battery degradation data across the fleet is far better than the folklore suggests, and the maintenance record so far is: nothing.

Who should and shouldn't switch

Four months in, my rule of thumb:

• High mileage + home charging: the saving is large and immediate. At 15,000 miles a year on an overnight tariff, I'm on track to save around £2,000 a year on fuel alone, before maintenance. Petrol at 160p makes the case stronger than when I switched at 150p.
• Average mileage (~7,000) + home charging: still clearly cheaper to run — roughly £950 a year saved on fuel — but whether it justifies changing car depends on what you'd be giving up and what you'd pay.
• No home charging: run the numbers with public charging prices, not the cheap home rates in the adverts. For most people in this position, the financial case isn't there yet. That may change as kerbside charging spreads and prices fall, but buy on today's numbers, not tomorrow's promises.

Frequently asked questions

Is it cheaper to run an electric car than petrol in the UK?
Usually, if you can charge at home. On an overnight EV tariff (~8p/kWh) an efficient EV costs roughly 2–3p a mile versus around 16p for a 45mpg petrol car at 160p a litre. At the standard capped electricity rate it's still roughly half the cost of petrol. Relying on public rapid chargers, however, can cost more per mile than petrol.

How much does it cost to charge an EV at home?
A Model Y Long Range's usable battery is around 75kWh. A full charge costs about £6 on an 8p overnight tariff, or about £19.60 at the July 2026 price cap rate of 26.11p/kWh. In practice you top up rather than filling from empty.

Do electric cars pay road tax?
Yes — EVs have paid VED since April 2025.

Is a used electric car a good buy?
Used EV values fell sharply over 2023–25, so second-hand buyers benefit from depreciation the first owner absorbed. Check battery health where possible — fleet-wide data shows degradation is slower than commonly feared.

What if I can't charge at home?
Run the sums using public charging prices (often 70–85p/kWh at rapid chargers), not home tariff rates. For many without home charging, an EV currently costs as much per mile as petrol, or more.