- Most people see a 10% to 15% increase in their monthly electricity bill with an electric car if they have an off-peak or dynamic pricing tariff. This equates to an additional £7.50 for every £50 spent.
- The most expensive way to charge an electric car at home is with a standard rate tariff, which going by the current energy price cap costs 29p per kWh.
- You need to work out your cost per mile in your ICE car to determine whether switching to an electric vehicle makes financial sense. In most cases it does.
You’re thinking about getting an electric vehicle. You love the potential savings on maintenance, but what about your home electricity bill? Will charging an electric vehicle break the bank?
It depends on what electricity unit rate you pay and how many units you use – sounds obvious, but EV owners can access cheaper rates than standard tariffs.
For example, British gas offers an EV tariff, as does E.ON, Octopus Energy, and most other energy suppliers. Taking one of these out will save you a packet on your electricity bill and is the key to making EV ownership make economical sense.
Another way to save money on your electricity bill charging an electric car is with solar panels – solar EV chargers let you tap into your solar feed and charge your car with it. Alternatively, you can hook your charger up to your battery storage system – same effect, only you can now charge with stored solar electricity day and night.
We explain more below.
How much will my electricity bill go up?
Let’s get down to brass tacks. The latest Ofgem price cap puts energy prices up 5% to 29p/kWh for electricity from 1 January 2024.
The average EV driver needs around 158 kWh per month*, which at a standard unit rate of 29p/kWh costs £45.82. However, using off-peak rates of 7.5p per kWh or less from EV tariffs reduces this significantly to £11.85 per month. You need a smart charger that can respond to time-varying rates like the Ohme ePod or Pod Point Solo 3 to get a cheap EV tariff.
*158 kWh equates to 474 miles if you achieve 3 miles per kWh – a relatively conservative figure under normal conditions. Achieve 3.6 miles per kWh and you’ll get 568 miles with 158 kWh.
For most people, an electricity bill increase of 10% to 15% is normal – so, if you pay £140 per month now, expect your bill to go up by £14 to £21.
According to Uswitch, the average electricity bill in the UK as of 1 October 2023 is £738.45 per year – that’s without factoring in the annual electricity standing charge.
Overall, your electricity bill won’t sky rocket with an EV, and shopping around for an EV-friendly energy tariff will keep your monthly charging costs low.
Working out your cost per mile in your ICE car
It goes without saying that regardless of the amount of money an electric car adds to your electricity bill, the factor that really matters is whether it works out cheaper than fuelling and driving your ICE car.
To work out your cost per mile in your ICE car, use the Fleet News Fuel Cost Calculator – for example, here’s the result for a Volvo V60 2.0 B3P:
- Total fuel cost: £43.23
- Gallons of fuel: 5.43
- Litres of fuel: 24.69
- Mileage: 250 miles per month
- Fuel type: Unleaded
- Fuel price used for this calculation: 155.89 pence per litre
- Mpg used for this calculation: 41.00mpg
The calculation above tells me that it costs £43.23 to drive 250 miles. The next question is whether I can drive 250 miles for less than £43.23 in an electric car.
To answer that, let’s say I don’t have an EV tariff and I pay the maximum price cap rate of 29p per kWh to charge my car at home. £43 will give me 148kWh of battery energy. If I achieve a 3 miles per kWh, I’ll get 444 miles of out it. That’s considerably more miles than I get from the petrol Volvo – making an electric car cheaper to run.
Home charging costs in a bit more detail
If you drive less than average and only need to add 40kWh to your monthly electric usage, here is how the maths works out:
40kWh x 29p/kWh = £11.60
And if you add 60kWh:
60kWh x 29p/kWh = £17.40
And if you add 100 kWh:
100kWh x 29p/kWh = £29.00
But that’s not the end of it because these are the prices for standard electricity rates – you can get cheaper deals with off-peak tariffs.
Understanding Off-Peak Rates
Now let’s focus on off-peak electricity rates specifically. These are lower priced overnight rates offered on many off-peak and EV tariffs when grid demand is reduced.
There are two main types:
- Two-rate tariffs offer cheaper electricity overnight, typically from midnight to 5am. These let you charge your EV inexpensively overnight, or run appliances like washing machines. If you fully utilise overnight rates, two-rate EV tariffs can cost less than the Energy Price Cap protecting standard deals.
- Single-rate tariffs charge the same rate all day. They usually offer a discounted rate for EV owners or perks like bill credits. Currently, most major suppliers don’t offer single-rate EV tariffs, so two-rate tariffs are your best bet.
Charging during off-peak hours can significantly lower your EV charging costs. Here’s how the savings work out:
20kWh off-peak rate:
20kWh x 7.5p/kWh = £1.50
60kWh off-peak rate:
60kWh x 7.5p/kWh = £4.50
As you can see, using off-peak charging reduces EV charging costs dramatically, even for high mileage drivers, keeping your monthly EV charging bill low.
EV Electricity Tariffs
In addition to off-peak rates, some energy providers offer special EV electricity tariffs with competitive pricing. When comparing plans, here are key factors to consider:
- Off-peak hours – Make sure they fit your charging needs.
- Unit rates – Compare peak vs off-peak pence/kWh.
- Standing charge – A daily connection fee of 50-60p.
- Incentives – Upfront bill credits or free miles for signing up.
Saving money with solar panels
Solar panels require a significant upfront investment of £5k to £15k on average with the addition of battery storage adding up to 30% to the price.
According to Greenmatch, those with high energy usage can expect payback or cost neutrality within 10 years. So, installing solar panels to charge your electric car isn’t going to save you any money in the short term – but it will in the long run.
So, how much does your electric bill go up with electric car? If you pay the standard price cap rate of 29p per kWh, you pay £29 per 100 kWh, which gets you around 300-miles of range at 3 miles per kWh.
By shopping around for an EV tariff with low off-peak rates, you can minimise the impact of electric vehicle charging on your energy bills. An off-peak tariff can cost as little as £0.075 pence per kWh, reducing that 100 kWh charge to £7.50.
Of course, achieving a better miles per kWh and taking less short journeys in the car is the key to charging less. Remember – real-world EV range is very different to WLTP figures, so you need to keep your wits about you when eking out range.