A guide to EVs (UK)
Car Buying
Range is relative.. The specified range is perfectly achievable for mixed roads, national limit country roads, etc. Efficiency drops significantly for motorways, so don’t expect to do the badge range.
Look at EV Database (ev-database.org) for more detailed range specs. It will provide a motorway range, the expected range in winter conditions, efficiency and expected charging speeds.
To work out range, consider using “A Better Route Planner” for a journey you might take. You can see how far the car will take you and what options you might have for charging.
Used car caution list: Nissan Leaf (Batteries need to be carefully assessed, unusual charger), Renault Zoe (Onboard Charger failures, not all cars have DC Rapid. Also watch out if the battery on the Zoe is owned or leased)
Efficiency
You can find typical efficiency on EV database. The following factors will affect efficiency
- Speed, particularly motorway speeds. So if you have range concerns, you can drop back to 60mph and see a significant increase in efficiency. (Not that this should happen often, but something to remember)
- Weather, rain / a wet road will reduce efficiency by 20%
- Wind, tailwind good, headwind bad.
- Temperature (IE Winter)
So on a rainy day with a headwind, you may find that you can’t make it to preplanned charging stops. Tesla / Apple Carplay / Google maps will *typically* help you replan along the way through the car nav
Winter
Range will drop somewhat, how much depends if the car has a heatpump, how sophisticated the thermal management in the car is, etc.
You don’t have heat from the engine to keep your screen wash warm. You may wish to use something rated to a lower temperature than you might have used in a conventional car.
Preconditioning is a wonderful thing… You can defrost your most cars via an app from bed.
Charging
Home Charging
Octopus offer good rates, particularly if you have a charger compatible with Intelligent Octopus
Good chargers: Ohme, Zappi, Hypervolt
I wouldn’t buy: ProjectEV, BG, Rolec
Public Charging
Get an Octopus electroverse card, there is a small discount for Intelligent Octopus Go users, covers a huge variety of chargers. General naming follows the convention Rapid (DC, 50-350kw, ~30 mins charge), Fast (7-22kw ~ 8hr charge) and Slow (2-3.6kw ~ 24hr charge).
Ovo Charge and Shell recharge are other options, but they tend to be a little more expensive.
Maps (UK):
Electroverse provides good info on chargers and pricing.
Zap-map - Provides more up to date user feedback
“Rapid” DC Charging:
All rapids in the UK will support contactless payments from November 2024. Rapid chargers will have charging cables attached. Almost all cars these days will be the CCS standard, so very little to worry about as far as compatibility. (Exceptions; Mostly Nissan older Japanese cars, inc Leaf)
Great:
Tesla Superchargers (Fast, consistent, 40% cheaper than the average). Note: only *some* chargers are available to all users. It depends on the site (exclusivity agreements, etc), utilisation levels, and so forth. You need to use the Tesla app to find which chargers are open to all and activate the charger
Good:
Ionity (Fast, 20% cheaper than the average)
Osprey (Consistent, if expensive)
Instavolt (Consistent, if expensive)
Bad:
Geniepoint (Expensive, unreliable)
BP Pulse (Unreliable, Except new large M&S installs)
Charging Place Scotland. (Make sure your accommodation has a charger or take a petrol car…)
DC Rapid Charging - Charging Curves
Batteries will have a charging curve.. Above is an example from a Tesla Model 3, showing the maximum charge speed supported by the battery at a given state of charge.
At 10% charge, 250kw (!) is possible. At 50% charge, it’s more like 90kw.
This means two stops from 10%-50% will be faster in my car than one stop of 10%-90%. You should look at the charging curve for your car, they do vary.
This doesn’t mean you need to run your battery down low, maybe 25% is a good point to charge as you start to get familiar with the charging network, and 10-20% as you build confidence. You want to leave some energy to divert to another charger should there be a problem. Even the most reliable networks aren’t 100%, e.g. there can be power cuts to the site.
For longer trips, you might try to plan to stop somewhere you want to dwell for a little anyway, a supermarket, a service station, a farm shop, etc, etc.
DC “Rapid” - Getting a good charging speed
The charge rates above this assumes that the charger is capable of supplying sufficient power. Note that a lot of chargers are current limited. The badge speed (“350kw”) is based on 800v battery voltage, but most cars are 400v. This means that a 350kw charger will only deliver 175kw to most cars. Nothing you can do about this (Other than buy a car with 800v architecture), just explaining why you see slower speeds.
Chargers may also deliver slower speeds in some specific circumstances, typically the AC-DC converters are split across several boards of maybe 10kw each. If one board fails, you’ll see 40kw from a 50kw charger. Load sharing is also possible, 1x50kw charger might have 2 connectors, if both are in use you may see 25kw.
An additional constraint is battery temperature. For rapid charging, you need a warm battery pack. Most cars will have a way of preconditioning the battery for rapid charging, this means that the car will either stop cooling the battery or actively heat the battery (which uses energy).
What does this mean for you? The key thing to remember is that it’s faster and more efficient to charge when you’ve already got a warm pack, charge at the end of a long journey, not at the beginning. And you should have a look at how you precondition the battery for your specific car.
“Fast” AC Charging
You normally need to use the “Type 2” cable which typically comes with the car. It’s common to need to activate the charging using an app or an RFID card. This is where the electroverse card comes in handy, as councils, garden centres, etc have made deals with a variety of different suppliers.
Fast charging is much slower than rapid charging, typically 7-11kw, so 4-8 hours to fully charge a car. Typically you’ll find Fast chargers in places like council car parks, hotels and airbnbs. You may be able to charge when you’re visiting a town on holiday.
They’re normally cheaper than Rapid DC chargers, but prices vary…
Changing rates from Fast AC chargers can be limited by the charger you connect to (Perhaps 7kw, perhaps 22kw) and the charger onboard your car (Perhaps 7kw, perhaps 11kw, rarely 22kw). You can find your AC charger speed on EV database. This is why you might see 11kw from a charger sold as 22kw
A charger at a hotel/airbnb is often a huge benefit, you can typically put filter on searches. That said, it’s not unknown for Airbnbs in particular to offer a plug for a granny charger and call this an EV charger, so it’s best to ask and also check how much they want for the electric…
“Slow / Granny” AC Charging
Cars will sometimes include a 3 pin domestic plug “Granny” charger. These pull a constant 2.4kw, which will take 24-48 hours to fully charge a car. As the charge is constant, it puts some strain on the electric. You should check how modern the electrics are before plugging in, if you suspect that the wiring is old, best not to charge. Also be careful with outdoor sockets where you suspect corrosion has occured.
If you’re at guest accommodation, it’s best to ask before you plug in, and you’d expect to pay for the electric you use.
Etiquette
It’s expected that you’ll come, unplug and move the car as soon as your rapid charge is complete. For Fast public chargers, the requirement isn’t as strict - you should try and get off the charger if it isn’t a major inconvenience.
Battery care
Avoid “storing” the battery above 80%. The damage from storing above this level is time based, so charging to 100% overnight and leaving the next day isn’t a big problem. Leaving it at 100% for days on end as a habit is.
Check EV database for your battery chemistry. LFP needs to be charged to 100% somewhat regularly to calibrate the battery management system.
DC Rapid charging has very little impact on battery health vs more gentle AC charging.