Are electric cars cheaper to run than normal cars?

Which is a cheaper way to propel an automotive vehicle - domestic electricity or petrol/diesel? Now you can find out.

Posted: Sun 01 May, 2016, 23:07

In the UK today, electric vehicles (EV) account for just 1% of all new car purchases. This seems like a crazily low amount considering the many, many benefits of EV ownership. So I thought I would work through the various potential issues that would put people off an electric car, starting with the fuel costs. We may care deeply about Planet Earth but few of us are prepared to shoulder a significant financial burden in order to save it. Most of us need to know that an EV, as well as reducing our reliance on fossil fuels, will also work out the same or cheaper than their current car. Not asking for much are we ?!

So how do the costs break down? Well I have owned a Renault Zoe since the turn of the year and been asked on many occasions whether it is cheaper than running a normal car. By normal I mean, you know... those dirty, noisy, smelly things that most of us drive around. Having driven an EV for just a few months this is actually how I am starting to see petrol and diesel cars. I had no idea I would be come so fanatical so quickly. But that is a separate topic for another day.

We cannot compare on the basis of miles per litre, as of course one cannot buy a litre of electricity, so lets compare in terms of pence per mile. Lets look at diesel costs first based on an average fuel consumption of (something most cars will average out and be able to tell you on the dashboard) of 44.4 mpg. This is a fairly typical, if not better than average.

Diesel Costs
ConversionDescriptionRateUnit
Miles per gallon44.4miles per gallon
To litresMiles per litre9.38miles per litre
To cost per mileAt 90p per litre9.2pence per mile
To cost per mileAt 100p per litre10.2pence per mile
To cost per mileAt 110p per litre11.3pence per mile
To cost per mileAt 120p per litre12.3pence per mile
To cost per mileAt 130p per litre13.3pence per mile
To cost per mileAt 140p per litre14.3pence per mile

Now diesel costs 102 pence per litre at the pumps, so it will cost just over 10 pence per mile given this fuel economy.

Now lets look at EV costs, based on the numbers from a Renault Zoe:

EV Costs
ConversionDescriptionRateUnit
Time to charge3.5hours
Home charger power rating7kilowatts (kW)
Energy to charge24.5kWh
To cost per mileAt 50 miles per charge and 7 pence/kWh3.4pence per mile
To cost per mileAt 50 miles per charge and 14 pence/kWh6.9pence per mile
To cost per mileAt 60 miles per charge and 7 pence/kWh2.8pence per mile
To cost per mileAt 60 miles per charge and 14 pence/kWh5.6pence per mile

These prices are actual prices on offer today from Scottish Power using their Economy 7 tariff. With Economy 7, power is cheaper overnight when demand is lowest. The Renault Zoe has a charging timer so it is possible to schedule the charging to happen at say 2am when the lower price electrity is available.

I regularly achieve the expected range of 60 miles on a full charge, so this is not unrealistic based on my typical usage. So on this basis, the EV will cost 2.8 pence per mile. Even with today's historically low fuel prices and pretty good diesel fuel economy, an EV fuel costs are just a quarter of a conventional car. In reality, fuel costs can be even lower as it possible to charge your car at public charging points for free (as well as get free parking). Charging points are widely available and it is even possible to check their availability from chargeyourcar.co.uk.

There are plenty of other factors to consider however fuel costs are much cheaper when running a typical EV car compared to a normal car. Surprised? Yes, me too. It does seem like the best kept secret, that it could be this good and yet noone is really aware. But this is the view of others as well. So the best thing to do is not to tell anyone, get an EV and enjoy it.

charging

EV Calculation

For me (more than anything!) here is an example of the calculation to get cost of 2.8 pence per mile:

CalculationResult
Total Energy to charge24.5 kWh
Charge cost at 7p/kWh24.5 * 7 = 171.5 pence
Pence per mile from full charge171.5 pence / 60 miles
=2.86 pence per mile