Rapid Development?

Guest contributor and EVA Scotland member Dr Mike Gill (of WattsUp fame) outlines his perspective on the development of the rapid charging infrastructure in Scotland.

Guest contributor and EVA Scotland member Dr Mike Gill (of WattsUp fame) outlines his perspective on the development of the rapid charging infrastructure in Scotland.

Expensive to install. Relatively costly to use. So, why are we seeing the more rapid growth of 50kW+ electric vehicle charging infrastructure compared to cheaper, lower powered equipment?

In April 2014, Transport Evolved published spyshots of Tesla’s first Supercharger location in the UK. South Mimms motorway services on London’s orbital M25 motorway was chosen to host what were at the time, and - incredibly - still are to this day (March 2019), the most powerful chargers available for any production EV in Britain.

Tesla made a bet. They decided that drivers’ needs would be best met by electric cars with high battery capacities and capable of replenishing those batteries in a short time. It would be technically difficult to produce such a car and they would cost a small fortune for prospective owners. (Of course, however, they weren’t entirely sure and briefly dabbled in battery swap technology in a similar vein to efforts made by the ‘Better Place’ company using the Renault Fluence).

It was a bold bet. At the time, other manufacturers were producing cheaper cars with much smaller battery capacities. The Tesla Roadster and then Model S were premium products with the price tag to match. But, having the fastest chargers was a huge selling point and enabled owners to make journeys which would have had the most ardent EV supporter at the time breaking out in a cold, range anxiety-induced sweat.

Although they did produce the fastest charger, Tesla weren’t the first to install high-powered EV charge points. Nissan saw the benefit of offering owners access to CHAdeMO chargers installed at dealerships and, in an effort to kickstart the EV revolution, Ecotricity rolled out a network of DBT chargers capable of delivering 43kW AC or nearly 50kW DC power. They too saw the benefit of enabling long distance travel for those owners who needed to go further than the limited range of their 2011 Nissan LEAFs or Mitsubishi iMievs.

Fast forward to 2019. Tesla now have 46 Supercharger sites (averaging just over seven 120kW chargers at each) across the UK with more to come this year. Year-on-year, 2018 recorded a 64% increase in the number of rapid charge connectors compared to 2017. Over the same period, public ‘fast’ chargers (7 - 22kW) saw a lower rate of growth with a 31% increase in connections. In 2019, BP Chargemaster will roll out 150kW chargers across the country. New operators are entering the UK market too with Ionity expected to install several 175kW chargers later this year. We’ll also see FastNed develop a six charger site at Newcastle University and expand their presence in the Greater London area after securing a contract with TfL.

There’s no doubt that chargers capable of 50kW (and more) are needed for longer journeys. As more EVs enter the market capable of over 200 miles, drivers are right to expect that their new, expensive cars will cover the majority of use cases.

But why aren’t we seeing similar growth rates for fast chargers? The received wisdom had always been that, as a greater proportion of journeys became possible with bigger battery capacity cars, we would be more likely to see a proliferation of destination charging.

From an operator’s perspective, and in a competitive market, the following comment may provide some degree of explanation. In response to a query on providing both fast and rapid chargers at a hotel site:

“Ideally, that’s the best solution, but for me, it’s about maximising utility. 50kW rapid requires an 80A incoming supply. Dual 7kW unit requires 64A supply. Some of our rapids charge up to 15 vehicles per day or more. A dual 7kW unit would likely only charge two vehicles per day."
(Personal opinion, Tom Callow, Director of Communication & Strategy, BP Chargemaster)

So, from an industry perspective, there can be higher turnover of cars from the same connection. In all likelihood, those drivers may also be willing to pay a little more for the convenience of a quicker charge. Making a profit from public EV charging is notoriously difficult but it’s possible that the most likely source of revenue will accrue from offering a premium ‘rapid’ amenity. Of course, BP Chargemaster employ a subscription service (as well as offering pay-as-you-go via Polar Instant) and, therefore, this makes the all-important per kWh price lower than their competitors. A pricing model with which not everyone agrees but is clearly attractive to both regular and fleet users.

Is it the end of fast charging? Absolutely not. The ability to charge at a slower rate whilst idle at home or at work is an enabler for the adoption of EVs. Charging at 3 - 7kW has benefits for the electrical grid at national and local levels. Undoubtedly, it makes sense for EV batteries to be used to store energy from renewable electricity sources.

However, it’s potentially a harder business case to make for private companies to invest in slower charging infrastructure. The margins are less and, once a driver has plugged in for the day, that socket is unavailable to others (unless, of course, there has been the foresight to install load sharing units!).

Critically, in my own view, informing drivers of where chargers have been installed will remain an important issue for some time to come. It’s not yet commonplace for rapid chargers to be installed in pairs or in hubs and so, although longer range cars are less likely to be stranded, having live information to guide drivers to the most suitable place to stop will be invaluable. By doing so, we can use the current infrastructure as efficiently as possible and minimise the inconvenience for drivers who otherwise may need to wait for a charge.

We’re going to need far more chargers than currently available and, with both the public and Government getting behind the electric motoring revolution, perhaps we’re finally at an inflection point. There have been several false dawns but we have to believe that the end of internal combustion engines is nigh. Roll on 2020, here’s to the future.


Dr. Mike Gill
WattsUp Developer

Transport Evolved, 21st April 2014