12 Mistakes You Must Avoid When Buying An EV Charger

By Finn Peacock – Chartered Electrical Engineer, Ex-CSIRO, Electric Car Owner, and Founder of SolarQuotes

Last Updated: 13th Feb 2024

Finn Peacock with an electric car charger

Me and my EV charger – that catastrophically failed 3 times in just 2 years!

So you’ve just bought, or plan to buy an new electric car. Great choice. But how will you charge your EV?

If you’re like most new electric car owners, you’re probably thinking about installing a dedicated, hard-wired charger at home. And I’m guessing you’ll soon be overwhelmed by all the EV charger brands out there.

You may also be daunted at the thought of finding an electrician with the experience to install and support the charger you choose.

I’m a Chartered Electrical Engineer who has designed control systems for nuclear power stations – and I made a dog’s breakfast of choosing an EV charger for my two electric cars!

But the good news is: I’ve made all the mistakes, so now you don’t have to.

I was initially going to title this article ‘7 mistakes Australians make when buying EV chargers’, but as I went through my list of shame – I ended up with 12 mistakes. Here they are, and how to avoid them.

Mistake #1 – Thinking you’ll get by with the trickle charger that comes with your car.

A typical mobile trickle EV charger

A typical mobile trickle charger that comes with most electric car models.

I’m nervous about putting this as Mistake #1. I just know I’m going to get roasted by many early-adopter electric car owners who will tell me how they’ve been happily trickle charging their car for the past 5 years.

They’ll tell me that buying a dedicated, fast charger is a waste of money when all you need is patience, forward planning, and a trickle charger plugged into a regular socket.

That device will recharge a modern, long-range electric car in…

…40 hours!

I’m guessing you’re not an early adopter happy to put up with such painfully slow charging. You want a device that can at least refill a long-range EV overnight. That means you can arrive home with a low charge and sleep soundly, knowing you’ll have a full battery when you wake.

And if you’re a solar power system owner, I’ll bet you want a charger fast enough and smart enough to take your surplus solar energy and put it into the car battery. Because electricity generated by rooftop solar panels in Australia is the cheapest energy in the world. 

But I accept there are some people who can get by with the trickle charger that came with their vehicle:

  • Electric motorbike owners
  • Plug-in hybrid (PHEV) owners – with a petrol engine and a tiny battery
  • Owners of small, low-range electric cars with small batteries 
  • EV advocates who have enough time, patience and planning prowess to get by

If you’re not on that list, don’t compromise your big investment in a state-of-the-art EV by skimping on your home charging. Invest in a hard-wired home EV charger

I spent a couple of months with only a mobile charger, and it was a pain in the bum. Don’t be like me; enjoy your new car to its full potential from the get-go.

Mistake #2 – Spending big bucks on a smart charger when you don’t need the smarts.

So you’ve decided to invest in a home charger. There are dozens of models, from dumb to super-smart. The smarter the EV charger, the more it costs. Be careful of spending big bucks on features sounding great in theory but you won’t use in practice.

Just one example: smart solar charging.

Solar smart charging is great if you have enough solar and your car is at home during the day. I work from home, have a smart solar charger and 20 kW of solar panels and most days my car happily charges on sunlight only.

But if your solar system is closer to 6.6 kW than 20kW, or your car is not at home most days, smart solar charging is likely to disappoint. I’ve found that most people transitioning from petrol cars just want their car to charge as fast as possible from cheap electricity when they plug in. Unless you have a nice big solar system, consider finding an electricity tariff that guarantees a cheap rate for EV charging (that might be overnight or during the day depending on your lifestyle) instead of relying on smart solar charging.

Mistake #3 – Buying a charger without OCPP

In my opinion, the most important feature in a charger is a nerdy thing called OCPP compatibility. 

OCPP simply means the charger is compatible with other OCPP products, apps and services. That means if you need smart features in the future, a third party can easily add them.

The third party could be an electricity retailer that can use it to temporarily stop charging your car when there are electricity price spikes, or even start charging when there is too much electricity on the grid – paying you to charge your car.

The third party could be an app automatically scheduling your charging to make the most of cheaper daytime or nighttime tariffs.

An OCPP compatible charger is as future-proof as possible. 

Mistake #4 – Buying a car-branded charger when you’ll need to charge other car brands in the future.

Car manufacturer branded EV chargers

Home chargers from Tesla, Ford, Mercedes & Hyundai.

Most car-branded chargers (including Tesla’s) are pretty dumb, lacking OCPP compatibility.

So, unless you are happy with a dumb charger, buy a third-party EV charger with the smarts you need.

Mistake #5 – Not Checking Cable Length Before You Buy

I didn’t think about charger cable length when I bought mine.  Unfortunately, the cable I got was one metre too short to charge my car if it was parked behind my wife’s.

That wasn’t the end of the world – but it was a pain in the bum moving cars around. I’ve since bought a new charger with a longer cable that works well for us:

EV charging cable length

If the charger you want to buy does not come with a long enough cable, ask if there is an ‘untethered’ version. Most have an untethered version, where you can BYO cable. Then you can jump online and buy a ‘Type 2 to Type 2″ charging cable long enough for your driveway.

Update: Since writing this, I have changed my charger (again!). I bought an untethered EV charger and a 10m long cable for even more flexibility. Now my wife no longer has to reverse in when she’s the last one home.

Mistake #6 – Not thinking ahead when buying a charger

If you’re a two-car household (or more), they’ll likely all be electric by the end of the decade. If you need to charge more than one car overnight, you’ll either need 2 chargers or you’ll have to jump out of bed at midnight to swap the cable to the other car.

Your house supply may or may not be able to handle two EV chargers running simultaneously, so you may need one that can ‘load balance’ with another charger. Also, when your installer is quoting for running the cables for the first charger, consider running cables for a future device at the same time to save money in the long term.

All these things are pretty technical – but worth talking through with a savvy installer who can ensure you are ready for more than one EV in the future.

Mistake #7 – Buying a charger that can’t handle Australian climate

Many EV chargers – like mine – are manufactured and/or designed in Europe and may not be developed with Australian conditions in mind.

In my experience, my Zappi charger (made in the UK) turned yellow from sun exposure, even though it’s mounted on a shaded, south-facing wall.  It also failed 3 times – and I suspect two of those failures were due to the Adelaide heat.

Update: The Zappi manufacturer claims two of the failures were due to ‘power surges’ in my home. No other devices failed when the Zappis failed.

A Zappi yellowing from the Australian sun

After approximately 1 year on a south-facing wall in Adelaide this is what my charger faceplate looked like. Compare it to the new one.

Ultimately, as EV chargers are a new and evolving market, it’s hard to predict which will go the distance. Make sure to check reviews written by other Australians to see if there are any common threads about reliability in our climate.

Mistake #8 – Sourcing a charger yourself and getting it installed by a local electrician.

This is a warranty nightmare waiting to happen.

I’ve had to claim warranty on my Zappi charger three times. Each time, the Australian website I bought it from flicked me over to the UK-based manufacturer. I managed to get replacements under warranty from them (2 chargers and one cable). But they just posted the hardware to me and made no effort to arrange the installation or cover the installation cost as per my rights under Australian Consumer Law.

Luckily I have about 500 solar electrician friends, but I’m a bit unusual like that. Most people would have to pay for the re-installation and then argue their case for compensation from the retailer or manufacturer.

I should have bought the EV charger from the same company that did the installation. Under Australian Consumer Law, the company that takes your money for supply-and-install is ultimately responsible for all warranty issues.  So I could have just returned to the installer when my charger failed. They would then have had to arrange a replacement and install it – saving me a whole load of hassle. 

Buying the hardware from the same company that does the installation also means the manufacturer can’t blame the installer or vice versa, with you stuck in the middle. You just get it fixed. Also, that means that a local installer will only supply and install hardware they are comfortable will easily outlast its warranty.

Mistake #9 – Not enough solar panels.

Ten years ago, I was proud of my 6 kW system boasting 250 W solar panels. It almost filled my large, north-facing roof beside my hot solar water.

Finn's rooftop solar installation

Today, 6 kW is considered small, and panels are typically 400 W each. And when I got two electric cars; horror of horrors, I started getting electricity bills after a decade of credits!

I’ve since added 14 kW of solar panels.  But if you buy a solar power system today, please size it appropriately.

Buying an electric car will significantly increase your electricity use. A typical Australian home uses 20 kWh per day. An electric car typically has a 60 kWh battery.

If your car is at home during the day, solar power can go a long way to offsetting most (or all) of the energy you need to charge your car – but only if your system is big enough.

The minimum system size I recommend elsewhere on this site is 10kW. But I always advise that you should go as large as you can reasonably fit and afford. Extra kilowatts are surprisingly affordable due to how the ‘solar rebate‘ works.

But if you have an electric car, look to at least 13 kW if possible – but bear in mind state-based network rules around maximum system sizes allowed.

Also keep in mind your solar power system, for various reasons, will rarely produce its rated output – especially in winter. Compare the output of a 6.6 kW system in the depths of winter compared to the height of summer:

Solar power system production - winter vs. summer

Mistake #10 – Not being on a “Time of Use” electricity tariff

Time of Use electricity tariffs

Time of Use Plus solar sponge tariff in SA

Time of use (ToU) electricity tariffs charge different rates for electricity depending on the time of day you’re using it.

ToU tariffs make charging an electric vehicle significantly cheaper, as the off-peak rate overnight and/or in the middle of the day is typically at least half of the daytime rate of a standard ‘flat’ electricity tariff (and can be even lower).

Most EV apps can ‘schedule’ charging at certain times. But in my experience, the settings are confusing and often incomplete. For example:

  • Tesla electric vehicles let you schedule a ‘charging on’ time but not a ‘charging off’ time. God knows why. 
  • BMWs/Minis let you schedule a charging on and off time – but won’t let you use them without a ‘scheduled departure time’.

It seems to me the cars have not been programmed to work well with Australian-style tariffs.

If you don’t want to rely on your car to control the off-peak charging, look for a device with off-peak functionality instead – or a charger with OCPP compatibility and a separate app to control it via OCPP (such as ChargeHQ).

But whatever you do, don’t predominantly charge your car from full-price grid electricity. Although it will still be cheaper than petrol, you are paying much more than you need to.

Mistake #11 – Draining a home battery to fill up your car battery

Home batteries and electric vehicles

If you have a home battery and an EV, you’ll need to ensure you understand and plan for how they will interact.

One thing you probably want to avoid is charging your EV with your home battery. This is a bad idea for a few reasons:

  • The efficiency losses between solar > battery > EV means you’ll lose energy transferring between them.
  • Your home battery energy will usually be more valuable avoiding peak tariff periods or participating in a Virtual Power Plant (VPP) than for charging your car.
  • The more often you drain your home battery, the quicker it will degrade.

But how can you control this?

The answer is for your EV charger installer to wire the EV charger to ignore your home battery. Remember, if you don’t want your home battery to discharge every time you charge your car (without enough solar generation to cover all the 7kW+ of charger power), get this in writing in the quote for the EV charger install. 

Mistake #12 – Installing a single-phase charger on a 3 phase supply.

A standard single-phase charger will work fine on a home with a 3 phase supply. But, I’d argue most 3-phase homes should install a 3-phase charger.

If you need the speed of a 3-phase charger, it’s nice to have it. And if you want to charge slower, all 3 phase chargers can be throttled down.

If you are going to the expense of running cable and mounting an EV charger, it’s probably worth going 3-phase if you have the capacity.

I installed a single-phase charger on my 3-phase home and regretted it so much I paid again to upgrade to a 3-phase charger. 

The next step

So there you have it – the mistakes you should avoid when buying an EV charger, based on my experience owning two electric cars for years.

If you’ve recently bought or plan to buy an EV, I have a network of pre-vetted installers who can provide a quote for the supply and installation of a good-quality charger to suit your situation.

Simply hit the button below to be taken to my quote form:

Happy EV driving,

Finn Peacock, founder of SolarQuotes.com.au

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