You can charge an electric car in the rain, but if yours breaks down you shouldn’t tow it yourself. Here’s what you need to know about living with an electric car
It’s easy to make assumptions or build up misconceptions about electric cars. Did you know, for example, that while electric vehicles (or EVs) are typically cheap to run, there are times when they’re more expensive than comparable diesel cars? If you’re a new electric car owner, or thinking of getting one, here’s our myth-busting guide to the realities of going electric.
According to figures from the Society of Motoring Manufacturers and Traders (SMMT), published by EV charge point mapping app Zap Map, there are now more than 250,000 electric cars on our roads.
That figure is forecast to rise to more than 12m in just over eight years, after the sale of new petrol and diesel cars is banned in 2030. So even if you’re not an electric car owner now, there’s a good chance you will be in the future.
To help you know what to expect, we’ve busted a few common electric car myths.
1) You can charge an electric car when it’s raining
Whether you can charge an EV in the rain is a query we get asked at Which?, along with questions about whether you can drive through deep puddles in an electric car.
The answer to all such questions is yes. You can charge in the rain, you can take an electric car through a car wash and if you have to traverse a flooded road, you won’t be electrocuted (just make sure you adhere to the car’s wading depth – check your manual for details).
Meanwhile, the standards for electric car charge points say the points must have a minimum waterproofing rating of IP44, which means they should be protected from water splashes from any angle – more than sufficient for all rain conditions.
Some charging operators have gone beyond this minimum standard, which should lend even more assurance. For example, Osprey is rolling out new charge points that have a rating of IP65, which means the electrics will be protected against jets of water from all angles, as well as being completely dust-tight.
2) Rapid chargers are only rapid for a battery’s first 80% of capacity
Rapid car chargers are able to fill a battery to 80% very quickly, but if you want your battery to be fully charged, expect to wait a bit longer.
To help protect the car’s batteries, the car will manage the amount of charge coming in. The fuller the battery, the slower the car will charge from that point.
As an example, the Volkswagen ID.3 (2020-) has a maximum DC charge rate of 100kW. This graph shows how the power from a 100kW charger decreased as the battery filled (its ‘state of charge’), when we monitored this in our lab.
As you can see, the car charged at 100kW up to around 30%, when the power started decreasing, then dropped off more sharply when it reached 80%.
In the case above, we found it took just 35 minutes to charge the 58kWh battery in the ID.3 from 10-80%. But it then took an extra 24 minutes just to get the car from 80% to 100%.
Because of this drop-off, and because you’re very unlikely to ever reach a rapid charge point with no battery left at all, rapid charge times are typically given as how long it would take to charge your battery from 10% to 80%.
3) Some public electric car chargers can be more expensive than diesel
Another issue with rapid chargers is that they can be expensive. You’ll typically pay 35p per kWh to charge your car at a rapid charger, or more for ultra-rapid, compared with a typical electricity cost of 19.19p per kWh if you’re able to charge at home on a standard tariff.
We’ve compared the cost of fuelling large diesel and large electric cars, across all the models we’ve reviewed under our current test programme, taking into account their average fuel efficiency and the current cost of diesel.
We’ve calculated that if you’re paying more than 33p/kWh to recharge an electric car using a rapid or ultra-rapid charger, you’ll be financially worse off than you would be fuelling a medium diesel car (or full petrol hybrid) to drive an equivalent distance.
Find out more about when it will cost you more to charge an electric car than fill a diesel by going to our electric car costs guide.
4) Batteries require more energy to charge than they can hold
This may sound counterintuitive, but to give you an example, we’ve recently tested the Mercedes EQC (2019-), a super-sized SUV. It has an 80kWh battery, but to charge it from 0% to 100%, we used 93kWh.
This head-scratcher isn’t unique to the Mercedes – it applies to all rechargeable batteries. We refer to it as ‘loss of charge’.
In our tests, we wrap this tested loss of charge into our average fuel efficiency assessments to provide a more accurate electricity use figure.
We then turn these figures into charging costs; you’ll find them in the tech specs of all our car reviews online. We also provide costs for petrol, diesel and hybrid cars, allowing you to compare day-to-day running costs between different cars and fuel types.
5) The EV market has its own ‘gas guzzlers’
There is a big difference in how much energy different electric cars use to travel the same distance – there are efficient EVs and EV equivalents of ‘gas guzzlers’.
We’re used to this concept in petrol and diesel cars. As a rule of thumb, big SUVs use a lot more fuel than small hatchbacks and city cars. Generally, the same is true of electric cars, and naturally it affects how much it will cost to keep your car running.
As an example, the tiny Seat Mii (2020-) city car is one of the most frugal EVs we’ve tested. It used just 17.3kWh per 100km in our tests, which is very low.
Based on average home energy rates of 19.19p per kWh, that would cost you around £480 to drive 9,000 miles (the average annual pre-Covid mileage driven by respondents to our last car survey).
Whereas the enormous Mercedes EQC (2019-), pictured above, is one of the least-efficient electric cars we’ve tested. In our tests it used 27.6kWh per 100km.
That increase of 10.3kWh per 100km to 27.6 per 100km equates to a total charging cost of £767 – nearly £300 more than the dinky Seat Mii.
While these differences might not be that surprising, there are some unexpected exceptions to the rule. The most efficient electric car we’ve tested is the Hyundai Ioniq EV – a large hatchback (similar in size to a Toyota Prius), which is substantially bigger than the tiny Seat Mii city car. It used an astonishingly low average of 16.3kWh per 100km in our tests, equating to just £453 to drive that 9,000 miles.
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