Electric vehicle charging at home: WA tariffs, costs, and smart strategies

More Western Australians plug in a new electric vehicle every month. The question that follows is always the same: what does it actually cost to charge one at home, and which Synergy tariff makes it cheapest?

Here's the short answer. Charging at home costs a fraction of filling a petrol tank, and the price you pay comes down almost entirely to your tariff. On Synergy's flat A1 rate, a typical Perth commuter spends about $72 a month. Move that same charging to the overnight EV Add-On window and it drops to roughly $43. Charge straight off your own rooftop solar during the day and it falls to nearly nothing. The rest of this guide shows you how each option stacks up, what a charger costs to install, and how to size solar so your car runs on sunshine.

What do you need to charge an EV at home?

Two things: a charger and a circuit to run it on. Most Perth households go with a wall-mounted Level 2 charger on its own dedicated circuit, which turns an overnight park into a full battery by morning.

How fast does each charging level charge?

Level	Power	Charging speed	Typical use
Level 1	2.4 kW (standard outlet)	~12 km/hour	Emergency or overnight top-up
Level 2	7.4 kW (dedicated circuit)	~40 km/hour	Recommended home charger
Level 2	22 kW (three-phase)	~120 km/hour	Fast home charging

Most Perth households install a Level 2 single-phase charger (7.4 kW). It fully charges a typical EV overnight, which is all a daily commuter needs. Three-phase 22 kW chargers are faster, but you only feel the difference if you regularly need a big top-up in a hurry.

How much does a home EV charger cost to install?

Two line items make up the bill: the charger unit and the electrical work to fit it. Figures vary by brand and by how far the electrician has to run a new circuit, but as a guide:

Charger unit: $800 to $2,500, depending on brand and smart features
Installation: $500 to $1,500 for the electrical work and a dedicated circuit
Total typical spend: $1,300 to $4,000

A smart charger that can schedule its own start time is worth the extra outlay. It's what lets you park up at 6pm and still only draw power inside your cheapest tariff window. For a run-through of the models Perth installers fit most often, see our guide to the best home EV chargers in Perth.

How much does it cost to charge an EV at home in Perth?

That depends on how far you drive and which tariff you charge on. Start with the driving, then apply the rate.

How much electricity does an EV use?

Most EVs use between 14–20 kWh per 100 km. A typical Perth household drives about 40 km a day, which works out to roughly 6 to 8 kWh of charging.

Put that on the clock for a month:

40 km/day × 30 days = 1,200 km
At 18 kWh/100km = 216 kWh a month

That 216 kWh figure is what the tariff comparison below is built on.

What does charging cost on each Synergy tariff?

Same 216 kWh a month, five different prices:

Tariff	Rate during charging	Monthly cost (216 kWh)	Annual cost
A1 (flat rate)	~33.26 c/kWh	~$72	~$862
Midday Saver (midday)	~8.85 c/kWh	~$19	~$229
Smart Home (off-peak, existing customers)	~17.4 c/kWh	~$38	~$452
EV Add-On (overnight)	~19.9 c/kWh	~$43	~$516
Solar self-consumption	$0	$0	$0

Now compare that to petrol. A similar-sized car doing 8L/100km at $1.89/L over the same 1,200 km costs about $181 a month, or roughly $2,177 a year. Even on the flat A1 rate, home charging saves you well over a grand a year.

Which Synergy tariffs suit EV charging?

Three plans are worth knowing about. One is built for EVs, one is closing to new customers, and one rewards you for charging in the middle of the day.

How does the EV Add-On tariff work?

Synergy's dedicated EV tariff bolts a cheaper overnight window onto your existing plan:

Overnight charging window: 11pm to 6am
Rate: around 19.9 c/kWh overnight
Requirements: a separate meter or smart meter that can record EV usage
Best for: overnight charging when you don't have solar

It's the current option Synergy points new EV owners to, so if you can't charge during daylight, this is usually the plan to ask about.

What about the Smart Home Plan?

The Smart Home Plan is a time-of-use plan that suited EV owners well. It's no longer open to new Synergy customers. If you're already on it, the overnight off-peak rate still works nicely for charging:

Off-peak rate (9pm to 7am): around 17.4 c/kWh, below the A1 flat rate
No dedicated EV meter required
Peak rate (3pm to 9pm): around 63 c/kWh, so keep the car off charge in that window

If you want the full picture of who this plan still helps, read our Synergy Smart Home Plan guide. For new customers chasing a cheap overnight rate, the EV Add-On is the plan to look at instead.

How does Midday Saver charging with solar work?

If you're home during the day and have solar, Midday Saver is the sweet spot. You soak up your own generation first, then top up on a cheap grid rate if the sun isn't quite keeping up:

Grid rate at midday: ~8.85 c/kWh when your solar falls short
Solar self-consumption: effectively free
Best for: work-from-home households and daytime charging

It's the same logic behind using Midday Saver against the A1 tariff: shift your big loads into the cheapest hours of the day.

What's the cheapest way to charge your EV?

Pick the strategy that matches your day. If you're home when the sun's up, solar wins. If the car's out all day and back at night, the overnight rate is your friend.

Strategy 1: charge from solar (best savings)

If you have a 6.6 kW or larger solar system, charge your EV during the day while the panels are working.

Cost: effectively $0 from solar self-consumption
Requirements: daytime charging, so you're plugging in while the sun's still up
Smart charger feature: some chargers detect surplus solar and draw only from the excess

It isn't quite free, since that solar could have earned you a few cents a kWh as a feed-in credit instead. But as running costs go, it's about as close to free as charging gets.

Annual saving vs the A1 tariff: about $862

Strategy 2: EV Add-On night charging

For households that drive during the day and charge overnight:

Schedule the charger for the 11pm to 6am window
The overnight rate applies to everything you draw in that window
Cost: about $516 a year for a typical commute
Annual saving vs the A1 tariff: about $346

Strategy 3: solar, battery, and EV together

The full electrified setup runs like this:

Solar charges the home battery during the day
The battery powers the house through the evening
The EV charges overnight on the cheapest rate, or
The EV charges straight from solar during the day

With well-scheduled charging, this can pull your EV running costs down to roughly $50 to $100 a year. The exact figure depends on your system size, driving pattern, and how much surplus solar you have to spare. Our solar, battery, and EV combo guide walks through how the three pieces work together.

How much extra solar do you need for an EV?

Adding an EV adds roughly 6 to 8 kWh of daily electricity demand. To cover that from your own roof:

Extra solar to add: around 2 to 3 kW of panels
On a 5 kW system? Consider stepping up to 7 to 8 kW
On a 6.6 kW system? You may already have enough midday surplus to cover it

These are rules of thumb, not a fixed answer, since your real number depends on when you drive and when you charge. For a closer look, see our guide to sizing solar for an EV, then use BillWise's scenario tool to model the impact on your own bills.

Can your EV power your home? V2H and V2G

Vehicle-to-Home (V2H) and Vehicle-to-Grid (V2G) let your car's battery push power back out:

V2H: run your home off the EV battery during expensive peak hours
V2G: export power from the EV to the grid for credits
Status in WA: not widely available yet, though some vehicles support it with a compatible charger

A typical EV battery holds somewhere between 60 and 100 kWh, which is far more than any dedicated home battery. Once V2H becomes mainstream, that car in the driveway could double as your biggest energy store. Our V2H and V2G explainer for Perth covers where the technology stands today.

Which home charger should you buy in Perth?

A few options cover most Perth driveways, depending on whether you want the cheapest reliable box or full solar smarts.

Budget option

Any 7.4 kW Mode 3 charger with a built-in timer
Set the timer for your cheapest tariff window
From around $1,300 installed

Smart option

A solar-aware charger such as a Zappi or Tesla Wall Connector
Automatically shifts charging to use your excess solar
From around $1,800 installed

Premium option

A three-phase 22 kW charger with solar integration
Fast charging plus full app control
From around $2,500 installed

If you're leaning toward the solar-aware route, our Zappi solar EV charger guide digs into how surplus-solar charging works in practice.

How do you work out your own EV charging costs?

Your real cost depends on your tariff, your solar system, how far you drive, and your charger setup. BillWise can model the lot:

Upload your bill and we'll read your current tariff and usage
Run an EV scenario to add EV charging and see the impact
Compare tariff options to find the cheapest charging plan for your profile

Start your EV cost analysis →

The bottom line: charging an EV at home in Perth costs a fraction of running a petrol car. Get the setup right, with surplus solar by day and the EV Add-On rate by night, and you're charging for just a few cents a kWh.

EV charging at home: everything you need to know: our complete guide to home EV charging setup, equipment, and installation in WA.
Best home EV chargers in Perth: the models Perth installers fit most, compared on price and features.
Solar, battery, and EV combo: how the three work together for the lowest running cost.

Ready to compare EV charging costs? Calculate your savings → includes a petrol vs EV comparison using current WA fuel prices, so you can see exactly what switching saves you.