Home electric vehicle charging is where most EV owners top up their cars, and it is usually the cheapest place to do it. Understanding the variables below will help you make a sensible choice, and ask the right questions, before booking an EV charger installation.
Your two options for home EV charging
Option 1: a portable cable in a standard power point
Most electric cars can charge from an ordinary 10 amp power point using a portable charging cable. Some cars include one; with others it is an optional extra.
A 10 amp outlet supplies about 2.3 kW. For a typical EV, that adds somewhere between 10 and 15 kilometres of range for every hour plugged in. Overnight, over 10 or 12 hours, that is roughly 100 to 180 km.
If you drive 30 to 50 km a day and park in the garage every night, that may be all you need. Plenty of owners never install anything more.
Portable charging does have limits worth respecting:
- It draws a steady, heavy load for hours. A tired power point, a loose connection or a circuit shared with other big appliances can overheat. Have an electrician check the outlet before you rely on it every night.
- Car makers generally warn against extension leads and power boards. Plug directly into the wall.
- Some portable chargers use a 15 amp plug with a wider earth pin. These need a 15 amp outlet, and the plug should never be altered to fit a 10 amp socket.
Option 2: a dedicated wall charger
A wall charger, sometimes called a wallbox, is permanently wired to its own circuit. On the single-phase supply found in most Queensland homes, wall chargers are commonly rated around 7 kW. That is about three times the speed of a power point, enough to add 35 to 45 km of range an hour.
Homes with three-phase power can use larger chargers, typically 11 kW or 22 kW. Whether that makes your car charge faster depends on the car, which the next section explains.
A wall charger tends to make sense if you:
- regularly drive more than a portable cable can replace overnight
- have two EVs sharing one parking area
- want to fit charging into a short cheap-rate window
- want to charge from surplus rooftop solar, track usage, or manage the load on your switchboard
You may see these options called “Level 1” and “Level 2” charging. Those labels come from North America. Australian suppliers more often talk about portable versus fixed chargers, single-phase versus three-phase, and power in kW. The ultra-fast DC chargers you see on highways are commercial equipment and are not installed in homes.
How fast will your car actually charge?
A common surprise is buying a powerful charger and seeing no improvement. That happens because charging speed is set by the weakest part of the system, not the strongest.
The supply point. A power point tops out around 2.3 kW. A wall charger can deliver more, up to what its circuit allows.
The car’s on-board charger. Home charging uses AC power, which the car converts to DC to store in the battery. The converter inside the car has a maximum rating. If that rating is 7 kW, an 11 kW charger will still only deliver 7 kW. Some models can only accept single-phase AC at all, so three-phase power gives them nothing extra. Check your car’s specifications for its maximum AC charging rate before choosing a charger. The Australian Government’s Green Vehicle Guide also lists energy use for many models.
The household supply. Your home’s connection is shared between the charger and everything else running. Some chargers automatically slow down when the air conditioner, oven and hot water system are all running, which protects the supply but stretches charging time.
As a rough planning guide, for a car using around 15 to 20 kWh per 100 km:
| Home setup | Approx. power | Approx. range added per hour |
|---|---|---|
| Portable cable, 10 A power point | 2.3 kW | 10–15 km |
| Single-phase wall charger | 7 kW | 35–45 km |
| Three-phase wall charger, car accepts 11 kW | 11 kW | 55–70 km |
Real-world results also depend on the battery’s state of charge and temperature. Most cars slow charging as the battery approaches full, and on hot days the car may divert some energy to cooling the battery.
To work out your own number, divide the charging power by your car’s energy use. A car using 18 kWh per 100 km on a 7 kW charger gains about 7 ÷ 0.18 = 39 km per hour.
Is your home ready for a wall charger?
Whether a wall charger is a straightforward job or a bigger project comes down to your property’s electrical setup. Every electric car charger installation should start with a licensed electrician checking the following. If you would like this done for your home, our team can assess your property for a wall charger.
Supply type. Most Queensland homes have single-phase power. Some newer or larger homes have three-phase. Changing from single to three-phase involves your distribution network, Energex in south-east Queensland or Ergon Energy in regional areas, and is rarely justified by EV charging alone.
Switchboard. The board needs room for a new circuit and suitable safety switches. Older boards, particularly those still using ceramic fuses, may need upgrading first, which we can handle as part of our switchboard and electrical installation work.
Household demand. A 7 kW charger running at the same time as ducted air conditioning, an electric hot water system and a pool pump can push a home past what its supply can safely deliver. Rather than upgrading the supply, many installations use load management, which lets the charger watch household demand and dial back automatically.
Distance and access. A charger on the garage wall beside the meter box needs a short cable run. A carport on the far side of the house, a detached garage or a run that needs trenching takes more time and material.
Protection devices. EV charging circuits need residual current protection suited to EV charging, including protection against DC fault currents. Depending on the charger, this is built into the unit or added at the switchboard. Your electrician will match it to the charger and the Australian Wiring Rules, AS/NZS 3000.
Network requirements. Energex and Ergon set rules for connecting equipment such as EV chargers, which can affect the size of charger allowed or require load limiting. These are checked for your address.
Fixed EV charger installation is electrical work, and in Queensland it must be carried out by a licensed electrical contractor, as set out by the Electrical Safety Office. When the job is finished, the installation should be tested and you should receive certification that it is safe and compliant. This is not a job for DIY.
Units and townhouses. If you live in a strata property, you will need body corporate approval before any work starts. Shared supply capacity, where the charger is wired from, and how the electricity is metered and paid for all need to be agreed.
What affects the cost of an EV charger installation?
Two neighbours can buy the same charger and pay very different amounts to have it installed. The charger is only part of the price; the rest depends on the work your property needs.
- Charger features. A basic unit costs less than a smart charger with app control, scheduling, solar tracking and load management. Tethered models, with the cable attached, are priced differently from socket-only models.
- Cable run. The longer and more complicated the route from switchboard to parking spot, the more cable and labour are involved. Running through ceilings, walls or underground adds time.
- Switchboard work. Adding a circuit to a modern board with spare space is simple. Replacing protection devices or upgrading an older board is a separate cost.
- Monitoring and load management. Solar-matching and load-managed chargers usually need a sensor installed at the switchboard.
- Mounting location. Outdoor installations need a suitably weather-rated charger, and brick or concrete walls take longer to fix to than timber.
- Supply upgrades. Uncommon, but if your supply needs upgrading, the network is involved and timeframes and costs increase.
Because these factors vary so much, an accurate price normally depends on an electrician assessing the switchboard, the supply and the path to where the car parks. For a price based on your home, request an EV charger installation quote.
What does it cost to charge at home?
Home EV charging costs are easy to estimate once you know two figures: how much energy your car uses, and what you pay for each kilowatt-hour (kWh).
Here is the method, using round example numbers rather than any particular plan:
- A car uses 17 kWh per 100 km and is driven 12,000 km a year. That is about 2,040 kWh.
- Some energy is lost in charging, often around 10%. So the car draws roughly 2,250 kWh from the wall.
- Multiply by your rate. At 30 cents per kWh, that is about $675 a year, or 5.6 cents per km. At 15 cents per kWh, it is about $340 a year, or 2.8 cents per km.
Substitute your own car’s energy use, your annual distance and your actual tariff to get a figure that means something for your household. Your bill shows your current rates, and the government’s Energy Made Easy website lets you compare plans for your postcode.
Choosing a tariff that suits charging
The rate you charge at matters more than almost anything else. Worth looking at:
- Time-of-use plans, with lower prices at certain times of day. Overnight off-peak rates suit cars that are away during the day.
- Plans with cheap or free midday hours. As rooftop solar floods the grid in the middle of the day, some plans now price daytime electricity very low. These suit households where the car is home during the day.
- EV plans that some retailers offer, with a discounted charging window.
- Economy or controlled-load tariffs. Whether an EV charger can be connected to one depends on your network’s current rules. Ask your electrician and retailer.
Most cars and smart chargers let you schedule charging, so once you know your cheapest window you can set it and forget it.
Charging your EV with rooftop solar
If you already have solar panels, the financial case for solar EV charging is simple. Every kilowatt-hour you put into the car instead of exporting to the grid saves you the gap between what you would pay to buy that power and the feed-in tariff you would have earned for sending it out. With feed-in tariffs now well below retail prices, that gap is usually significant.
Whether it works for your household depends on some practical realities.
The car needs to be home in daylight. If it is parked at work from early morning to evening, solar charging is mostly a weekend option. Households where someone works from home, or with a second car that stays put, get far more benefit.
There is a minimum power level. AC charging generally cannot run below about 6 amps. On a single-phase charger that is roughly 1.4 kW of spare solar; on a three-phase charger it is about 4.1 kW. If your surplus falls below that, a solar-only setting will pause charging, or draw the difference from the grid, depending on how it is configured.
Weather and season change the output. Winter and cloudy days produce less, so most owners pair solar charging with a scheduled cheap-rate top-up to make sure the car is ready when needed.
Your system size matters. A small or older system may have little left over once the fridge, pool pump and daytime air conditioning have taken their share.
To follow your solar output, a charger needs to know what the panels are producing and what the house is using. That usually means either a current sensor at the switchboard or a direct connection to a compatible inverter. If solar EV charging is a priority, check compatibility with your existing inverter before choosing a charger, or ask your electrician which chargers work with your solar system.
What about a home battery? It can help, but EV batteries are typically several times larger than home batteries. A home battery is better suited to running the house in the evening than to filling a car.
Can your EV power your home?
Some EVs can send electricity back out, and there are three versions of this to know about:
- Vehicle-to-load (V2L): an outlet or adaptor on the car lets you run appliances or tools directly. It is available on a number of models today.
- Vehicle-to-home (V2H): the car supplies the house, for example in the evening or during an outage.
- Vehicle-to-grid (V2G): the car exports electricity to the grid.
Vehicle-to-home and vehicle-to-grid need a car that supports bidirectional charging, a compatible bidirectional charger and approval from your electricity network. Only a limited range of vehicles and chargers currently meet those requirements in Australia, and using the car’s battery this way may affect its warranty. Running the house during a blackout also requires the system to be designed for backup operation.
If you think you might want this in future, mention it when you get a quote. It may influence the charger and switchboard work that makes sense now.
A checklist before you choose a charger
Run through these before you buy anything. The answers will narrow your options quickly and make any quote easier to compare.
- How many kilometres do I drive on a normal day, and could a portable cable already cover that overnight?
- What is my car’s maximum AC charging rate, and does it accept three-phase?
- Does my home have single-phase or three-phase power?
- Is there space on my switchboard, and is the board in good condition?
- Do I want to charge from surplus solar, and will the charger work with my inverter?
- Will I need load management to avoid overloading my supply?
- Would I prefer a tethered cable or a socket for my own cable?
- Will the charger be outdoors, and is it rated for that?
- Which tariff will I charge on, and can I schedule charging to match it?
- Might I want vehicle-to-home charging in the future?
Common questions
Will any wall charger fit my car?
Most EVs sold new in Australia use a Type 2 connector for AC charging, so most wall chargers will be compatible. Some older or imported models use a different connector, so check your car’s charging port before buying.
Can I put a charger in a rental property?
Only with the owner’s written permission, and in a unit complex the body corporate must also approve it.
Do I need a smart charger?
Not necessarily. If your car can schedule charging and you don’t need solar tracking or load management, a simpler charger may be enough. Smart features are worth paying for when they solve a real problem for your home.
Can I still charge on the road?
Yes. Public fast chargers, including the Queensland Government’s Electric Super Highway along major routes and a growing number of commercial networks, cover longer trips. Your car’s navigation or a charging app will show locations and live availability.
