One of the most consistent surprises for new EV owners is discovering how dramatically their home charging cost can vary depending on how they set it up. Two drivers with identical cars and identical daily mileage can pay wildly different amounts to charge — not because of anything to do with the car, but because of tariff choice and a five-minute scheduling decision.
Home charging cost facts
- Charging at home on a standard flat tariff costs roughly 2–4p per mile for a typical EV.
- On an off-peak overnight tariff, that drops to 1–2p per mile — a saving of 40–60% on your electricity bill for the same mileage.
- Public DC rapid charging typically costs 12–25p per mile equivalent — five to ten times more than overnight home charging.
- A 7 kW home charger adds roughly 25–30 miles of range per hour — enough to fully charge most EVs overnight from a low state.
Why the tariff you are on matters more than the charger you buy
Most discussions of home EV charging focus on hardware — which wall charger to buy, what cable to use, whether you need a smart charger. These are real questions, but they sit downstream of a more important decision: what electricity tariff are you on?
Standard flat-rate tariffs charge the same price per kWh at 2 am as they do at 6 pm. Time-of-use tariffs charge significantly less during overnight hours when grid demand is low. The difference can be substantial — in the UK, a standard rate might be 25–35p per kWh, while an EV-specific overnight rate might be 7–10p. For a 60 kWh battery charged from empty, that is the difference between paying roughly £18 and £5 for the same charge. Multiply that across a full year of ownership and the tariff choice dwarfs the cost of any charger upgrade.
Smart chargers vs. scheduling in the car
You do not need a smart charger to benefit from off-peak electricity. Most modern EVs have a built-in departure schedule that lets you set the time you want the car ready by. The car works backwards from that time and the current state of charge to decide when to start charging, ensuring it hits 80% (or whatever limit you have set) just in time for your departure. This built-in scheduling is free and works perfectly well with any home outlet or wall charger.
A dedicated smart charger adds value in a different way: it typically provides per-session cost tracking, remote control from a smartphone app, integration with solar if you have it, and sometimes direct integration with your energy tariff for automatic smart scheduling. If those features matter to you, a smart charger is a worthwhile investment. If you simply want to charge cheaply overnight, the car's own scheduling gets you there without any additional hardware.
Three-pin vs. dedicated wall charger
A standard three-pin plug with the Mode 2 cable supplied with most EVs works for overnight charging in many situations. It delivers 2–3 kW, which translates to roughly 8–10 miles of range added per hour — enough to recover 60–80 miles overnight from a depleted battery, which covers most daily use cases.
The limitations appear when daily mileage is higher, when you arrive home later and have fewer charging hours available, or when the three-pin socket is on an older ring circuit that is not rated for continuous high load. A dedicated 7 kW Type 2 wall charger delivers two to three times as much range per hour and is rated for continuous overnight use. For most EV owners who drive more than 40 miles per day, the installation cost — typically £500–£900 after any available government grant — pays back within one to two years of reduced energy cost versus public charging.
Solar charging: the best case scenario
For homes with rooftop solar panels, EV charging can become extraordinarily cheap — potentially free during daylight hours when generation exceeds household consumption. A smart charger or home energy management system that detects surplus solar generation and diverts it to the EV can reduce annual charging costs to near zero for lower-mileage drivers in summer months.
The practical caveat is that solar charging works best for daytime charging windows, which conflicts with the overnight departure-time scheduling that most working drivers prefer. Bi-directional chargers and home battery systems can bridge this gap, though both add upfront cost. For drivers whose work schedule allows charging during the day or who have home batteries, solar integration is genuinely worth exploring with an installer.
Reference sources
This guide was written in original language for Momentum Cards by 20PercentFuel using public guidance from reputable transport and energy sources.
Questions drivers often ask
What is the cheapest time to charge an EV at home?
On time-of-use tariffs, the cheapest window is typically between 11 pm and 6 am. Exact hours vary by provider and tariff. A smart charger or vehicle scheduling lets you automate charging within this window.
Do I need a smart charger to charge cheaply?
Not necessarily — most EVs allow departure-time scheduling within the car's own settings, which achieves the same off-peak result without a third-party smart charger. A dedicated smart charger adds more flexibility and data.
How much cheaper is home charging versus public rapid charging?
Home charging on a standard tariff costs roughly 3–6 times less per mile than public DC fast charging. On an off-peak tariff the saving is even larger — sometimes 5–8 times less per mile.
Is a dedicated home charger worth the installation cost?
For most EV owners who charge regularly at home, a dedicated 7 kW wall charger pays back its installation cost within one to two years compared to using a standard three-pin plug with an EVSE cable.
Can I charge an EV on a normal household plug?
Yes, using a standard 3-pin plug with a Mode 2 cable (usually supplied with the car). This is called granny charging and delivers about 8–10 miles of range per hour — fine for overnight use but slow for high daily mileage.