Smart EV Charging Australia: How to Charge Your Car for Free Using Solar

The typical Australian EV driver spends $600-$900 per year charging from the grid. With rooftop solar and a smart charger, that number can drop to near zero. This guide explains how smart charging works, what equipment you need, and what a real charging day actually looks like on a standard 6.6kW solar system.

What Makes a Charger “Smart”

A basic EV charger does one thing: supply power when a car is plugged in. It charges at full power from the grid, regardless of the time, what your solar panels are producing, or how much other appliances in your home are drawing.

A smart charger adds a control layer that changes when and how much power is supplied:

• Scheduling - charge only during off-peak tariff windows (e.g. 11pm-7am)
• Solar diversion - increase or decrease charge rate in real time based on available solar surplus
• Load management - reduce charge rate if the household’s total draw approaches the supply limit
• Remote control - start, stop, or modify sessions from a phone app

Each of these saves money differently. Scheduling saves on tariff arbitrage. Solar diversion turns exported solar into free range. Load management prevents expensive switchboard upgrades.

Option 1: Off-Peak Scheduling (No Solar Required)

If you don’t have solar, off-peak scheduling is the simplest way to reduce your charging cost. Most Australian retailers offer time-of-use tariffs:

Tariff Period	Typical Rate	Charge Speed Cost
Peak (4pm-9pm)	35-42 c/kWh	$2.60-$3.10 per 10kWh
Shoulder (7am-4pm, 9pm-11pm)	22-28 c/kWh	$1.60-$2.10 per 10kWh
Off-peak (11pm-7am)	15-20 c/kWh	$1.10-$1.50 per 10kWh

Set your smart charger to start at 11pm. For a driver covering 15,000km/year at 15kWh/100km (consuming ~2,250kWh annually), the difference between peak-only charging at 38c and off-peak at 18c is approximately $450 per year.

Any smart charger supports scheduling. The Evnex E2 Core at $999, the Tesla Wall Connector at $800, and the Wallbox Pulsar Plus at $1,345 all offer this. You do not need a solar-specific charger for scheduling alone.

Option 2: Solar Diversion (The Free Charging Method)

Solar diversion is the feature that enables genuinely free EV charging. Here is how it works:

1. A CT clamp (current transformer) is installed on your main supply cable during charger installation. It monitors power flowing in and out of your home in real time.
2. During daylight hours, when your solar panels generate more than your home is consuming, the excess would normally export to the grid at 3-6 c/kWh.
3. Instead, the smart charger detects this surplus and diverts it into your EV - at the same effective cost as the export rate, i.e. near zero.
4. If generation drops (cloud cover, afternoon), the charger reduces its output automatically to avoid drawing from the grid.

The minimum charging threshold for most chargers is 1.4kW (the minimum AC charging rate). Your solar system needs to be generating at least 1.4kW of surplus above your home consumption to trigger solar divert mode. On a typical sunny day with a 6.6kW system, this window runs from roughly 9am to 3pm.

What a Full Solar Charging Day Looks Like

Scenario: 6.6kW solar system, Sydney, clear April day. Household base load 0.4kW (no major appliances running). Car parked at home 8am-5pm.

Time	Solar Output	House Load	Surplus	Charger Action	Range Added
8:00am	1.2kW	0.4kW	0.8kW	Below threshold - standby	-
9:00am	2.8kW	0.4kW	2.4kW	Charging at 2.4kW	~14km/hr
10:30am	4.5kW	0.4kW	4.1kW	Charging at 4.1kW	~24km/hr
12:00pm	5.8kW	1.2kW (oven)	4.6kW	Charging at 4.6kW	~27km/hr
1:00pm	6.1kW	0.4kW	5.7kW	Charging at 5.7kW	~33km/hr
3:00pm	3.9kW	0.4kW	3.5kW	Charging at 3.5kW	~20km/hr
4:30pm	1.6kW	0.4kW	1.2kW	Below threshold - stops	-

Total free range added: approximately 120-140km from a single clear day. On an average Australian day (factoring cloud cover), a well-configured solar divert setup adds 50-80km of free range daily during warmer months.

Annual saving for a 15,000km/year driver replacing grid charging (at 35c/kWh) with solar: approximately $500-$700 per year.

Which Chargers Support Solar Diversion

Not all smart chargers have solar divert capability. The ones that do:

Charger	Solar Divert	Method	Price
Myenergi Zappi 7kW	Yes (ECO/ECO+ modes)	CT clamp	~$1,350
Fronius Wattpilot 11J	Yes	CT clamp or Fronius direct	~$1,800
Wallbox Pulsar Plus 7kW	Yes (Eco-Smart)	CT clamp	~$1,345
Evnex E2 Plus	Yes	CT clamp	~$1,299
ABB Terra AC 7kW	Yes	CT clamp	~$1,800

The Zappi is the most purpose-built solar divert charger - its ECO+ mode is specifically designed to maximise solar self-consumption and has the deepest field history in Australia.

The Fronius Wattpilot integrates directly with Fronius Solar.web for households that already have a Fronius inverter, offering more precise control without needing a CT clamp.

The Wallbox Pulsar Plus and Evnex E2 Plus offer solar divert as one feature among several - both also include OCPP, which the Zappi lacks.

Chargers that do not support solar diversion: Tesla Wall Connector, Delta AC Max, most budget smart chargers below $900.

Load Management: The Other Smart Feature Worth Having

Solar divert and scheduling get most of the attention, but load management is quietly the most practically important feature for older Australian homes.

Many Australian homes have 32A or 63A single-phase supply at the switchboard. A 7.4kW EV charger draws 32A on its own - at the limit of a 32A circuit, and a meaningful share of a 63A supply. Add a reverse-cycle air conditioner, an electric oven, and a dishwasher running simultaneously, and the circuit trips.

A charger with load management monitors total household draw and automatically reduces the charging rate if the sum approaches the supply limit. This prevents nuisance tripping and, critically, means many homes can avoid an expensive switchboard upgrade that might otherwise be required for an EV charger installation.

The Evnex E2 range, Wallbox Pulsar Plus, and Fronius Wattpilot all include dedicated load management. The Zappi relies on CT clamp data but handles load management less precisely.

Picking the Right Smart Charger

If your priority is…	Best option
Maximum solar self-consumption	Myenergi Zappi 7kW
Solar + OCPP + load management	Evnex E2 Plus or Wallbox Pulsar Plus
Fronius inverter integration	Fronius Wattpilot
Off-peak scheduling only (no solar)	Evnex E2 Core or Tesla Wall Connector
Budget with OCPP	Evnex E2 Flex ($799)

Installation Notes

Solar divert requires a CT clamp fitted to your main supply cable during installation. This is a 15-30 minute addition to a standard installation and adds minimal cost - typically $50-$100 in electrician time. Confirm with your installer that they will fit the CT clamp if you are using solar integration.

For full installation costs, see our EV charger installation cost guide. For detailed charger comparisons, see our best home EV charger guide. For solar-specific setup details, see our solar EV charging guide.