Real fuel efficiency of an electric car? 165MPG

I've been driving EVs for a few years now - and people often ask me about running costs. I can't tell you what your insurance, maintenance, or leasing costs will be - but I can show you how much it costs to drive.

Here's a fairly recent trip in my Renault Zoe:

That's a mixture of motorways in the cold, and gentle country paths in the summer. Hopefully typical of a mixed driving style.

It takes 971kWh of electricity to move 3,500 miles. So, what's that in MPG? Let's work it out the long way.

I pay 13p/kWh for my domestic electricity.

£0.13 * 971 = £126

So the cost per mile is...

£126 / 3,500 = 3.6p/mile

Currently, UK petrol prices are about £1.30 per litre. There are 4.55 litres to the UK gallon.

(4.55 litres * £1.30) / 3.6p/mile = 165 MPG

That's a pretty good fuel efficiency!

You can calculate it another way:

The 23MPG difference is then the market arbitrage between electricity and fossil fuel costs.

— Eugene Zaikonnikov🌻💛 ✊✌️ (@varjag) September 10, 2018

Now, this is just my car and my driving style. But the evidence is clear; electric driving is ridiculously cheap!

At the moment, if you're getting 50MPG in a petrol car, fuel costs 12p/mile.

(4.55 * £1.30) / 50 = £0.118

The best fossil-fuel cars get under 100MPG - that's still double the cost per mile of an electric car.

If you can supplement your home charging with solar, like I do, the cost per mile falls even further.