Charging your EV
Keeping an EV charged is not difficult. It just takes a bit of planning and forming good habits.
Safety is paramount always. Ensure all manufacturer’s instructions are followed when charging at home and away. Never use a charger that has been modified in any way or is in any way faulty. Ensure you consult a licensed electrical contractor to ensure your home charging set up is safe and suits the requirements of your home electrical set up.
Just like owners of petrol cars, some EV owners like to ‘top up’ regularly, while others prefer to ‘fill up’ when they see the battery getting low. Some EV owners charge at home most of the time, while others rely on charging at work, shopping centres, public charging stations and other locations. Most use a combination. It’s generally only for longer trips that you need to plan where you can charge.
Whether you already own an EV or plan to buy one, the following information will help you develop the optimal charging solution for your needs and priorities.
Optimising your charging
An EV’s battery life can be extended by avoiding charging it to 100% every time. A battery will be less stressed when only charged to around 80%. Of course, for longer trips, charging the battery to as full as possible is necessary. Talk to your EV dealer for more guidance on this topic.
Charging at home
You can charge your EV from a power point or buy dedicated Electric Vehicle Supply Equipment (EVSE) - note we use the more commonly used term of ‘charger’ throughout our web pages.
All EV’s come with a charging cable with a three-pin plug that can be plugged into any power point. The rate of charging will be determined by the amperage of the power point, which is usually 10A or 15A (~2.3 or 3.5kW), but will always be relatively slow.
For example, a 40kWh Nissan leaf will be charged from low to full in around 24 hours1. A 100kWh Tesla Model S would take longer.
But if your battery is rarely below half full, and you remember to charge overnight and/or while your solar PV system is operating, then this charging method could be fine for you most of the time. However, if you charge this way you won’t be able to access the cheaper economy electricity tariffs, as power points cannot be connected to an economy tariff. Time-of-Use tariffs can still be accessed.
If you have a public fast-charging station close by, you could use that when you don’t have hours to wait to fill up your battery.
Many EV owners also have a solar PV system and are keen to run their EV on renewable energy as much as possible (this excludes EV owners with a charger on an economy tariff). However, many EVs consume much more power than the existing solar PV system can provide. And it’s often challenging to charge an EV in the middle of the day when there is most likely to be excess PV generation.
The average EV uses around 10 kWh/day. The average 5 kW solar PV system generates around 23 kWh/day and exports around half that to the grid. Therefore, the average EV owner would need to have their EV connected to their dedicated EV charger for several hours in the middle of almost every day to maximise their EV charging from their PV system.
Of course, if the EV uses more than the average, or if the solar PV system is smaller or generating less excess electricity than the average, then it becomes harder to run your EV on renewable energy.
One solution is to install a battery energy storage system to store your renewable energy so you can use it when the sun goes down. This is still an expensive investment and the entire EV/PV/battery system needs to be carefully designed by an experienced professional to optimise the benefits and minimise the upfront and ongoing costs.
Many EV owners opt to pay extra money to have a dedicated charger installed in their garage. The advantages are:
- Faster charging, e.g. the 40kWh Nissan Leaf will charge from low to full in around 7.5 hours, two to three times faster than via a power point. This can be valuable when the car is used often and/or not at home for long periods, or you don’t want to be plugging it in regularly
- If you have a solar PV system, you can use the excess PV generation in the middle of the day (this excludes EV owners with a charger on an economy tariff)
- Access to economy tariffs, as an EV charger can be hard-wired to your electrical circuit
- Ability to maximise the benefit of Time-of-Use tariffs, as your charging can be completed within the cheaper rate periods
- Less electricity is lost when the charging occurs more quickly
- If your home has 3-phase electrical installation, you can install a 3-phase charger for the fastest and most convenient at-home charging possible
- Power point circuits are not typically designed to take a high load such as an EV charger for an extended period. A dedicated EV charger, installed by a licensed electrical contractor, may provide you with a safer solution, with a lower risk of electrical overloading.
Our Queensland Electricity Connection Manual (PDF 5.2 mb) (QECM) provides rules on the connection of equipment such as wall-mounted EV chargers. A typical 7kW (~32 Amp) single-phase EV charger can't be connected to a continuous supply (uncontrolled) tariff. It can only be connected to an economy, or controlled, tariff.
An economy tariff is available for at least 18 hours per day, and often only switched off for short periods in the morning and/or early evening, so your EV battery will still be fully or mostly charged when you need it to be.
If you want access to 24/7 charging at home at charging rates above 20A (~4.6 kW), your only option is to upgrade your electrical installation to 3-phase, and buy and have installed a 3-phase charger. However, this is only viable if your EV can accept a 3-phase charge.
If you have a typical single-phase dedicated EV charger rated at 32A (around 7 kW), you can only have it connected to an economy tariff (available for a minimum of 18 hours per day). If you have a single-phase dedicated EV charger rated up to 20A, or a 3-phase EV charger, it can be connected to a continuous supply (24-hour) tariff.
You can also use a Time of Use tariff and manage your EV charging – via your charger or your EV – so that it only, or mainly, occurs during the cheapest tariff periods.
So, depending on your lifestyle and affordability and convenience priorities, you can save money if you switch to an economy or Time-of-Use tariff for off peak charging. Using these tariffs is also good for the network as your EV charging is not adding to peak network demand, which could lead to expensive network upgrades and ultimately, higher electricity prices for all Queenslanders.
Remember, to charge on the economy tariffs, you must have a hard-wired dedicated EV charging point – using a power point isn't possible.
The electricity demand of a charging EV can be significant, even if only charging from a power point.
Well before you bring your new EV home, it’s critical that your proposed charging solution is evaluated by a licensed electrical contractor, ideally one who is experienced in installing EV charging systems (your EV dealer may have some recommendations).
They can test and evaluate the wiring from your switchboard to your garage and advise if any upgrades are necessary to support your desired charging arrangement, and to ensure the electrical safety of you and your home.
Be prepared for some potential additional costs, to cover upgrades to your switchboard, wiring, electricity metering and electrical safety measures if needed. You also need to consider the practicalities of charging at home, e.g. can you provide a suitably weatherproof and secure environment for charging?
Most houses have a single-phase electrical installation. Most EV chargers are single phase, and many EVs can only accept charge from a single-phase charger.
If your house has a 3-phase electrical installation, or you wish to upgrade to one and your EV can accept a 3-phase charge, you will gain some benefits like faster charging from installing a 3-phase charger. However, the set-up costs could be significant.
Buying an EV will increase your electricity bill, sometimes significantly. The average EV consuming 10 kWh/day on Tariff 11 will add over $200 to a quarterly electricity bill.
However, the power cost will be roughly 40% of the amount you would have spent on fuel for the same distance travelled (source Which Car?).
Whether you have a solar PV system or not, one way to reduce the environmental impact of your EV charging from the grid is to subscribe to GreenPower through your electricity retailer. In Queensland, an increasing percentage of grid-supplied electricity comes from renewable energy sources, thereby lowering the environmental impacts of EVs even further compared with normal cars.
Charging away from home
Charge your EV at public charging stations or possibly even at work.
The number of public EV charging stations in Queensland is increasing in both towns and on popular travel routes. You can generally charge your EV at a much faster rate at these charging stations than you could at home.
The rate of charge can vary from 25kW to 350kW DC, allowing you to charge your EV from low to full in as little as 30 minutes. However, the maximum rate of charge will be determined by your EV’s capability.
Check with the EV manufacturer or dealer for specific details and compatibility with various types of public charging stations. Different EVs have different standard plug types that may not be compatible with all charging stations. Adapter cables are available to increase your charging options if necessary.
Some EV dealers offer free charging to some customers for a period of time, at specific charging stations, as part of the EV purchase.
Some businesses, like hotels, tourist attractions and shopping centres, provide free or subsidised EV charging to their customers while using their business’s services. Other commercial public EV charging providers charge 20 to 50 cents/kWh.
Check out the public charging stations near you, and on your potential routes, on PlugShare and A Better Route Planner. More stations are being added all the time.
Some employers may be happy for you to charge at work when you need to, either from a dedicated EV charger or a power point. Always check with your employer before charging your EV at work.
Planning long trips
If you’d like to take a long trip in your EV, that’s quite feasible in most areas of Australia. You just need to research where public EV charging stations are on your route (try PlugShare), what type they are, and roughly how long it will take you to recharge based on the kilometres travelled.
You can then plan your breaks and overnight stays, and even your route, based on the charging locations. There’s a network of charging stations from Brisbane north to Cairns and west to Toowoomba.
Always check with accommodation providers before using their electricity and power point to charge your EV. If you’re visiting people, they may allow you to charge at their home.