Off Peak Charging Benefits | Grainger Motor Group Kia

The Real Cost Benefits of Off-Peak EV Charging

Charge your car from as low as £25 per 1000 miles (3p a mile)!

At Grainger Motor Group Kia, we have a fantastic range of new Kia vehicles and we wanted to provide you some information showing just how cheap they can be to drive.

The Cost Comparison

Driving 1,000 miles per month:
Electric Vehicle (Off-Peak Charging):

£25.24 per month (£302.89 per year)
Petrol Car (40 mpg, 173.5p/litre):

£197.19 per month (£2,366.28 per year)
Diesel Car (45 mpg, 200.20p/litre):

£202.23 per month (£2,426.76 per year)
That’s a saving of over £2,000 per year simply by charging at home using off-peak electricity in comparison to a Petrol or Diesel vehicle with efficient MPG.
How These Figures Are Calculated
- Distance driven: 1,000 miles per month
- Vehicle: Kia EV5 GT-Line S (81.4 kWh battery)
- Efficiency used: 3 miles per kWh (conservative estimate)
- Estimated range per full charge: ~245 miles
- Full charges required per month: 4.08
Electricity Costs:
- Off-peak rate: 7.6p per kWh (Octopus Energy Intelligent Octopus Go Tariff - Off peak rate)
- Cost per full charge: £5.35
- Total monthly cost (100% off-peak): £25.24
- Equivalent running cost: ~3p per mile
Other Charging Scenarios & Costs

We understand charging off-peak isn't always possible, so here are some examples of different charger use.
80% Off-Peak / 20% Standard Charging
- Monthly cost: £56.05
- Cost per mile: ~5.6p
- Occasional daytime charging increases cost slightly.
Based on using a home charger for 80% of total charging at an Intelligent Octopus Go off-peak rate of 7.6p/kWh, with the remaining 20% using public slow/fast chargers at an average of 54p/kWh.
50% Off-Peak / 25% Standard / 25% Rapid
- Monthly cost: ££131.31
- Cost per mile: ~13.1p
- Frequent use of public rapid chargers significantly increases cost.
Based on using a home charger for 50% of total charging at an Intelligent Octopus Go off-peak rate of 7.6p/kWh, 25% using standard public chargers at an average of 54p/kWh, and 25% using rapid public chargers at an assumed 89p/kWh.
Why Charging at Home Makes Sense

Massive Cost Savings
Home charging—especially off-peak—is dramatically cheaper than petrol.

Convenience
Charge overnight and wake up every morning with a full battery—no fuel station visits required.

Predictable Costs
Stable electricity rates make it easier to budget compared to fluctuating fuel prices.

Battery Health
Slower home charging is generally better for long-term battery condition than repeated rapid charging.

Greener Driving
Off-peak electricity often aligns with lower grid demand and increased renewable energy usage.
Final thoughts

Charging your EV at home, especially on an off-peak tariff, can reduce your driving costs to a fraction of petrol.

Even when using a mix of charging methods, electric driving remains significantly more affordable and far more convenient.
Monthly charging cost estimates are based on a total distance of 1,000 miles using the Kia EV5 GT-Line S 81.4kWh 214bhp Auto FWD. Calculations assume an average energy consumption rate of 3 miles per kWh, equating to an estimated range of 244.2 miles per full (100%) charge based on the vehicle’s 81.4kWh battery capacity. Electricity costs are calculated using the Octopus Energy Intelligent Octopus Go tariff off peak rate at 7.6 pence per kWh, with pricing accurate as of 5 October 2026. This provides a total cost of £25.24 per 1000 miles, which has been rounded down to £25 for the purpose of this advert. Estimated total charging costs are derived from these assumptions. Actual costs and range may vary depending on driving style, weather conditions, terrain, vehicle load, battery health, and real-world efficiency. Tariff rates are subject to change and may vary by region, eligibility, and charging times. Figures are provided for illustrative purposes only and do not guarantee actual performance or cost.