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What’s involved in the construction of an ultra-rapid electric car charging station?

Chargefox recently announced that they will build 21 ultra-rapid electric car charging stations along the main highways connecting Adelaide, Melbourne, Canberra, Sydney and Brisbane, plus some in Western Australia around Perth. The first to open will be in Euroa, roughly 160km and 2 hours from Melbourne, in the existing service area off the Hume, on the other side of the McDonalds car park (-36.742756, 145.590776 to be precise).

In just a few weeks, there will be two ABB Terra HP charging points capable of pumping 350kW of electricity into a compatible EV, two additional Tritium Veefil-RT units capable of 50kW, all sourcing power not only from the grid, but 150kW of solar panels and a 273kW/410kWh battery. This unique site is not only an Australian first, but one of the few worldwide capable of such rapid charging and utilising renewable energy.

I was lucky enough to cop a look at the site under construction and get a guided tour of all the bits involved in making the rapid charging site a reality. Strap yourselves in, as this is gonna be a deep dive into nerd territory.

Evan, Chargefox’s engineer, started me off at this transformer up on a pole in a field.

This unit is what connects the entire service station area to the power grid and is rated for 500kW. Plenty for the service station’s needs, but as you’ve probably realised, a 350kW charger, plus two 50kW chargers, is 450kW – not much left over for the service station is it? The solution to this problem is extremley nifty, but we’ll get to that later.

Electricity runs from the transformer in that field via a cable under the ground, to a switchboard attached to the service station building about 60 meters away.

The charging site grabs its power from the switchboard via cables that run across the servo and under the car park.

To get cabling from the edge of the building to the chargers another 20 meters or so away, the sparkies used a method called horizontal boring – a computer controlled drill head that they control with a joystick. This allowed them to avoid digging up the asphalt road, keeping disruptions at this busy site to a minimum.

The cable from the switchboard runs runs directly to a new concrete pad built to house a DC to AC inverter for some solar panels, a battery, a secondary switchboard and a big box from ABB containing two massive rectifiers. These rectifiers are part of ABB’s Terra HP charging system and take the AC power from the grid and turn it into DC power for the 350kW chargers. Here’s at this big boy’s guts:

The beauty of splitting the rectifier from the charging unit is that if a second car comes along and wants to charge, instead of having to install two 350kW sources of energy, which is expensive and would be rarely utilised, the charging site can deliver 175kW to each car, or 200kW to one car and 150kW to another – depending on the state of charge each car is in and what they can handle. Evan tells me that this flexibility is the main reason Chargefox went with ABB’s Terra HP system over others currently on the market.

To the left of the concrete pad housing the electrical gear is 50kW of solar panels. These panels will feed into entire service station area’s energy needs combining with the existing 100kW of panels on the Maccas building and the battery Chargefox has installed. See the concrete blocks at the bottom of these panels?

This is part of an ingenious system from 5B called “Maverick” that allows for large installations of solar panels to be deployed on bare land with minimal effort. Typically you’d have to install a bunch of poles, mount the panels and wire them all up. With this system, the panels are pre wired off site and the concrete blocks keep the panels on the ground. All you do is put them on the floor and pull them out along the ground like a series of paper dolls. Check out this video of an install in process:

The charge heads themselves, where people plug their cars in, consist of two Aussie designed Tritium Veefil-RT units that will each have a CHAdeMO and CCS port capable of supplying up to 50kW. The star of the show however is the ABB Terra HP High Power fast charger. It’ll supply up to 350kW of energy to a single car charging over CHAdeMO or CCS. Practically no EVs on the market can suck in electricity that quickly right now, but Chargefox are future proofing the site for the day cars come along that support such fast charging. At 350kW, it’s possible for a car with a 60kWh battery to be charged in around 10 minutes.

On the front of the charge head is an NFC reader and a small LCD. To get the electricity flowing, you just fire up the Chargefox app. All payment is handled via the app. The screen gives info on the amount of electricity being supplied, how long left until the car is full and how much it costs to charge up. There’s also the CCS & CHAdeMO plugs that have built in cooling, so that they don’t melt from all that electricity pulsing through.

Inside the charge head is a fibre optic cable back to the rectifiers and a 4G modem. This allows for Chargefox to remotely monitor each site, so if something goes wrong, they know immediately instead of waiting for a customer to report it. ABB themselves can also remotely access the chargers to apply software updates and conduct diagnostics.

Now, back to the start, where I mentioned that 500kW transformer and the 450kW of electricity needed to power the chargers at full tilt. As you read, this site has a 273kW/410kWh ABB battery (made up of Samsung cells) and over 150kW of solar panels (100kW is already on the roof of the service station and Chargefox is installing an additional 50kW). The vast majority of the time, the entire site will be run off the solar panels and the battery. Only when multiple cars come in asking for the full 450kW of charge will the grid really be utilised. This combination of solar and battery turns the grid connection into a backup power source for rare occassions. It was much cheaper to buy solar panels and a battery and install them, than to pay to upgrade the transformer, plus the site obtains the benefit of reducing it’s grid demand even further, reducing power pricing and carbon footprint. Win-win-win.

Here’s a picture of the entire setup operational. On the left are the two ABB Terra HP 350kW chargers. On the right are the two Tritium Veefil-RT units capable of 50kW.

I hope you enjoyed this look at what makes a rapid charging station tick. I’ve only showed you what is really, the last stage of getting a charging station into production. There’s obviously heaps of planning required before a shovel hits the ground or a dollar is spent. Check back into Drive Zero in a few weeks to see part one of a multi-part series outlining the process of planning and implementing Chargefox’s other site along the Hume, in Barnawartha North. If you liked this, you’ll love that!

Anthony also produces The Sizzle - a daily email newsletter covering all aspects of technology with an Australian point of view.

Notable Replies

  1. keith says:

    This is so awesomely nerdy. Love that insta-solar panel array. Great article @decryption!

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