Home vs public EV charging: which is cheaper?
Charging at home on a smart EV tariff is roughly 10× cheaper than the most expensive public rapid network and 3× cheaper than the cheapest. For a Tesla Model Y doing the UK average 7,400 miles a year:
Cheapest smart home
£150.63/yr
Octopus Energy Intelligent Octopus Go, 6.9p/kWh
Standard home tariff
£569.98/yr
Price cap, no smart slot
Cheapest public rapid
£1266.14/yr
Tesla Supercharger, 58.0p/kWh PAYG
Expensive public rapid
£2008.36/yr
InstaVolt, 92.0p/kWh PAYG
Modelled on Tesla Model Y at 295Wh/mile real-world × 7,400mi/year = 2183kWh/yr.
Per-session comparison
A full 0 → 100% charge on the same Tesla Model Y:
| Where | Rate | Total cost | Cost per mile |
|---|---|---|---|
| Octopus Energy Intelligent Octopus Go | 6.9p/kWh | £5.66 | 2.0p/mile |
| Tesla Supercharger (PAYG) | 58.0p/kWh | £47.56 | 17.1p/mile |
When public charging makes sense
- Long trips beyond your car's range — public ultra-rapids cost more per kWh but a 20-minute stop is the only practical option.
- You can't fit a home charger (flat, rented accommodation, no driveway). Off-street workplace charging or supermarket destination charging is the next best thing.
- You stay overnight somewhere with destination chargers — many are cheaper than rapid rates.