20 July 2023 EV Charging, Net Zero

How to use different types of public EV chargers

EV charger

The electric vehicle (EV) industry is rising, and installing EV charging is becoming more attractive. Research by Cornwall Insights, the independent energy research firm, has found, in the last year, a 70% rise in public EV chargers in the UK. It’s a surefire way to increase the value of your land or property.

The UK government is asking to install 300,000 EV chargers in the UK by 2030. However, there needs to be more guidance on what type of charger is needed. The critical thing is that the charging must be easy to use, convenient and should match the right time, location, and speed for EV drivers.

The different types of EV chargers

Looking to install EV charging at your site? It will help to understand the different types of public EV chargers out there. From slow, fast, rapid, and ultra-rapid charging, each EV charger has its pros and cons.

It’s time to demystify public EV chargers and explain what each can do. Here is an overview of the different types of chargers, to help you understand what EV drivers need. Before you know it, you’ll be ready to install your first public EV chargers and upgrade your site to start earning revenue.

Slow EV chargers

Slow charging will charge an electric vehicle at around 3kW/h and will mainly be used to charge at home, not in the public domain. Slow charging requires very little other than plugging into a 3-pin household socket in a wall. As a result, it can take a long time to fully charge an EV, with the majority of charging taking place overnight.

  • The typical battery size in an electric vehicle is around 60kWh. Charging this size battery using a slow charger will take nearly 20 hours for a full charge.

Pros and cons of slow chargers

It is a cheap way to charge and doesn’t require the installation of any charging infrastructure. However, it does take a long time to charge, more than a day if you need to fully charge from empty.

There is little in the way of protection this way and slow charging using a 3-pin plug should only be considered a temporary measure.

If you don’t have a driveway, you might have to run the charging cable across the pathways, causing a Health & Safety hazard. Cables trailing across public pavements are not allowed as they present a trip hazard and can get damaged over time.

Fast public EV chargers (AC Charging)

According to government statistics from Jan 2023, 57% of all public EV chargers in the UK are fast chargers. Fast chargers are the go-to charger for most EV drivers and charge’s using an alternating current (AC). EV drivers can access fast charging in the workplace and in public places such as car parks, retail and leisure sites.

Fast chargers can deliver power between 7kW and 22kW. Typically you’d be able to charge twice as quickly as slow chargers. It’s important to realise that whilst you may expect to charge even quicker at 22kW, not all electric vehicles today can charge at 22kW (using AC chargers), most EV’s will charge at no more than 11kW.

Using the typical 60kWh battery in an EV, charging at;

  • 7kW will take 8-9 hours for a full charge
  • 22kW will take 3-4 hours for a full charge

You can use a charger that is tethered (with a cable attached) or untethered (you provide your cable). As fast charging typically charges a vehicle overnight it will be one of the cheaper ways to publicly charge your vehicle. Packed full of built-in safety features they monitor voltage and current, especially in locations where there are multiple chargers.

Pros and cons of fast chargers

Fast chargers are convenient for charging a vehicle when parked for more than a short stay. Also known as “destination chargers,” they are ideal if somebody wants to charge up cheaply overnight or have a quick boost in a few hours. Installing fast chargers in the right location can make them the most convenient and cost effective way to charge.

Grazing mentality

While people can charge their battery fully in eight hours, it’s crucial to note daily commutes will rarely discharge a battery in full. The majority of charging made by EV drivers is a “top-up”. Drivers charging in public do so when they need to take a rest stop, using their time to also grab a drink or a meal. Fast charging can be seen much more like “grazing” charging when vehicles are already stationary, rather than specifically stopping for the sole purpose of charging.

Fast charging helps put the customer first

Public charging infrastructure must match customer needs. Fast charging can be ideal for someone who wants to charge overnight. Locations that install significant numbers of rapid chargers, and not considering customer behaviour first, will see a downturn in repeat customer visits and prevent sites bringing in new customers. It is vital that sites should always consider the right charger, in the right location, at the right speed.

Fast charging helps limit battery stress

Research suggests that EV battery health can be impacted by the type and speed of charging. Constant and regular rapid (or ultra-rapid) charging can reduce the efficiency of a battery. Drivers should try to use fast (or slow) charging as their main source of charging. Whilst miles driven will continue to be an important factor in the resale value of an EV, the health of the battery is likely to be equally so. Public fast charging is more convenient, cheaper and better for all.

Rapid public EV chargers (DC charging)

Rapid charging and ultra-rapid charging, delivers charge to a vehicle using a direct current (DC). This means the charge is delivered directly into the vehicle’s battery and can put more power in quickly. You will find rapid chargers alongside major roads or in motorway service areas.

This type of charging is anything upwards of 50kW to 100kW. When the battery reaches around 80% capacity, it will slow the speed of charging to avoid damaging the battery. This system is known as the “battery curve”.

  • Using the typical 60kWh battery in an EV, charging using a rapid charger could take less than an hour to fully charge.

However, the reality is, the time taken to fully charge can vary, and will depend on where and what time of day you charge, as well as the make and model of your EV. The advertised speed of a charger (e.g. 100kW) will typically occur when the battery charge is between 20% to 80%. EV’s self-regulate the speed of charging when the battery charge is below 20% and above 80%. It is not uncommon for charging between 80% and 100% to take twice as long as charging from 20% to 80%. Rapid charging units take up more space and will always have their own dedicated tethered cable for EV’s to connect to.

Pros and cons of rapid chargers

Rapid charging is ideal when people have limited time to charge and want a lot in a short space of time. Rapid charging is quick and convenient and can save drivers time. It is ideal when you are on a long journey and need to take a short rest break, typically less than 30 minutes. Rapid charging will be more expensive than fast charging, regular use will have an impact on battery health. It’s advisable not to rely on this type of charging.

Using the 80%

If you plan on using the UK rapid charging network, it is best to charge to 80% and then get on your way. This should be enough charge to get you home or to your destination, and will take a lot less time than charging to 100%. In fact, charging to 80% and making a second stop (to rest and charge) could take less time than charging to 100% in one go on the rapid charging network. Remember, the last 20% of charge can take 2-3 times as long as from 20% to 80%. When you reach your destination you can then plug into fast charging and benefit from a slower and cheaper charge.

Possible battery damage with long-term use

Using rapid chargers as your primary source of charging could reduce the health of your battery. Therefore, it’s best to use this type of charging when needed and use fast chargers as often as possible to limit the impact on the battery.

Ultra-rapid public EV chargers (DC charging)

Ultra-rapid charging is the fastest type of charging and also charges using direct current (DC). Ultra-rapid charging delivers speeds above 100kW up to an incredible 350kW. The charging time depends on the amount of power the charger has and the make and model of the EV. Very few vehicles on the road today will be able to achieve the advertised speed of 350kW’s.

  • Using the typical 60kWh battery in an EV, charging using an ultra-rapid charger will take about 20 minutes to reach 80% charge.

Pros and cons of ultra-rapid chargers

Rapid and ultra-rapid chargers deliver charge to a battery very quickly, they have built-in safety measures and advanced communication protocols. These features ensure efficient charging and help protect the battery by reducing the speed of charge at certain times. Long-term regular use of ultra-rapid chargers could be detrimental to the health of the battery.

Limited number of EVs can use it

While it might seem attractive to use Ultra-Rapid chargers, few EVs can take advantage of the highest speeds offered by them. It tends to be premium or luxury cars, such as Audi or Porsche that can be charged above 100kW. Drivers should be aware of the speed of charge their vehicle can take not just rely on the advertised speed of the charger.

Changes in utilisation habits

A recent joint Zapmap and Green Finance Institute report found a wide gap in ultra-rapid charge point utilisation habits. Charge point operators (CPOs) can use this information to create the best infrastructure.

Different EV charging times

Charging speeds are always subject to change, and it can depend on the state of charge of the battery, the vehicle type, and the technology. The table below shows a few examples of the different charging times for fast rapid and ultra-rapid chargers.

sms blog image

Using the Kia Niro as an example, here are the approximate speeds it will take to charge on different chargers.

AC charging (for a full charge)

  • 3kW AC charging will take 22hr 40 mins
  • 7kW AC charging will take 9hrs 42 mins

DC charging (to charge from 20% to 80%)

  • 50kW DC charging will take 49 mins
  • 100kW DC charging will take 31 minutes
  • 350kW DC charging will take 31 minutes

Wireless EV charging solutions

There is an alternative to charging with a cable – wireless EV charging. This is still a relatively new technology, but it is suggested that wireless charging may become readily available for certain road users. It is a solution that can allow road users such as bus and taxis to charge quickly without the need to plug in. The technology is currently undergoing trials, one such example is Nottingham City Council recently trialled wireless EV charging for the taxi rank outside the city centre railway station. The taxi drivers responded positively to the trial, feeling it was more convenient and saved them time.

Pros and cons of wireless charging

Wireless charging is still in its infancy. It may have limited benefits and use cases. The trials will help to better understand where the correct use of this technology will be and make sure any safety concerns are addressed before it is made widely available.

Installing the different types of public EV chargers

You can get ahead of the charging curve and install public EV chargers on your land or property. It’s a lucrative market on the rise. The information above can guide you in selecting the most suitable EV chargers for your site. After all, EV drivers will keep using the best chargers.

Work with an expert

Delivering essential energy infrastructure is what we do, and what we do best. From our work with leading telecoms companies designing, installing, and managing the electrical infrastructure that connects the UK’s 4G and 5G networks, to the national smart meter rollout where we fit more than 40,000 devices in homes and businesses each month. Our scale, engineering expertise, and agile approach to technology is why our customers are now choosing us to help them navigate the infrastructural challenges and growth opportunities of EV chargepoints.