“The demand is massive out there,” Simon Gallagher, MD of eSmart Networks, said, talking to Current± about delivering electric vehicle (EV) charging hubs and infrastructure.
eSmart Networks – which specialises in high voltage infrastructure for high-power EV charging hubs – is looking to deliver around 100 high-power, therefore 100kW plus, hubs this year.
“The grid sits at the centre of it all,” Gallagher said, giving the example of hubs with between six and 12 high-power chargers.
“The biggest unknown costs, and the biggest variable by far is the grid connection”.
While a site with lots of traffic can seem attractive, if there’s no grid infrastructure there, costs can easily skyrocket, making the site unviable.
As such, eSmart Networks finds capacity on the grid, with companies then using that capacity map to plot their locations- or vice versa, where companies will present a list of sites they think are attractive, and eSmart Networks will assess them for the grid.
“It is one of the more painful elements of the process for connecting these hubs. It's got massive uncertainty and massive risk,” Gallagher said.
He also gave the example of EV forecourts, such as GRIDSERVE’s Braintree forecourt, which has a 33kV connection and 6MW capacity. Gallagher said that every time a site of that size is built, it’s equivalent to putting a town of around 5,000 houses on the network, which he said wasn’t really designed for that in the first place.
As such, capacity is getting more and more constrained.
“There are developers who are going to lose out, because the capacity just isn't on the network. The biggest challenge is all around capacity.”
However, there are mitigation strategies that can be deployed, including battery storage. Gallagher said that the company has done a few high-power charging hubs where the grid capacity isn’t there yet, but because of reinforcement works will be in around five years.
“We install battery banks to bridge that gap between now and the future,” he said, adding it’s “more of a stopgap” as the general pattern of usage at an EV charging hub doesn’t necessarily suit batteries that well.
High-power EV chargers need large amounts of power fairly instantaneously, meaning the batteries often don’t have time during the day to recharge- and while Gallagher said there is an argument they’ll recharge overnight, “you would need a huge battery to supply 350kW charging all day long”.
Currently though, with usage being less intense, battery storage is a useful mitigation measure, while Gallagher added that the technology has a huge role to play in grid balancing, but that eventually the networks will be reinforced while other measures such as overnight charging will come into play.
He gave the example of a recent EV charging installation for a bus depot in London, which needed a large grid connection where there wasn’t sufficient capacity. eSmart Networks mapped the network and worked out what capacity there was during the day, which was 1MW. The bus depot needed 3MW.
Overnight though, when the load dies down on the high voltage network, capacity increases. There is now a timed connection in place for the depot, meaning that during the day, the depot takes 1MW, then overnight that jumps to 3MW, which is enough energy to charge all the buses.
There is also equipment installed there so that if the depot did try to take more than 1MW during the day, it would be disconnected.
eSmart Networks itself has three areas of its business – EV charging connections, renewable energy connections and industrial and commercial connections.
"At the centre of the three things, and what we're all about, is the grid," he finished.