EV Charging Off-Grid: The Real Deal for Aussie Off-Grid Living

So you want to run an electric vehicle off-grid? Good. Here's what the maths actually looks like before you start stringing cable across the yard.

This is a practical breakdown of EV charging hardware, the power it pulls, and what an off-grid system has to deliver to handle it. I'm writing from Central Queensland where the sun is generous and the grid is sometimes not, so the numbers below are tuned for a realistic Australian off-grid setup.

The Three Charging Levels, Translated to Off-Grid Load

EV chargers are split into three levels based on power delivered (Transport for NSW). Knowing which level your car actually draws is the starting point for sizing solar, batteries, and inverter.

• Level 1 (AC slow): 1.4 kW to 3.7 kW from a standard 10–15 A household power point. Adds roughly 10 to 20 km of range per hour (Transport for NSW; Elite Power Group). Fine for plug-in hybrids with small batteries, marginal for a full BEV.
• Level 2 (AC dedicated): 7 kW to 22 kW on a dedicated circuit with its own plug or socket. Adds 30 to 130 km of range per hour (Transport for NSW). This is the realistic home charging tier for off-grid Australia.
• Level 3 (DC fast): 25 kW up to 350 kW (Transport for NSW) or up to 400 kW in some commercial units (Elite Power Group). Adds 150 to 300 km of range per hour, some vehicles fully charged in 10 to 15 minutes (Transport for NSW). Almost never appropriate for off-grid home use.

Off-grid, Level 2 at 7 kW single-phase is the practical ceiling for a standalone house system. Anything above that and you are buying industrial-grade kit and a diesel generator as backup.

Plugs and What Actually Lands in Your Driveway

Standard plug types sold new in Australia:

• Type 2 (Mennekes): AC charging, the standard home and destination plug (Transport for NSW; Elite Power Group).
• CCS2: DC fast-charging, the standard for new EVs in Australia (Transport for NSW).
• CHAdeMO: Older DC standard, being phased out of new Australian model line-ups.

Since 1 January 2020, all new EVs sold in Australia have both AC and DC plugs as standard (Transport for NSW). CCS2 is the dominant DC plug on new vehicles from Tesla, Hyundai, Kia, BMW, and VW. If you are installing infrastructure today, CCS2 is the correct new-installation standard for fast DC capability.

The Numbers That Actually Matter Off-Grid

The headline figures circulating online tend to undersell EV energy demand. Here is what verified Australian sources say:

• An EV travels about 6 km per kWh of stored charge (Solar Quotes).
• Driving 100 km uses about 16 kWh (Solar Quotes).
• Real-world Australian EV efficiency sits around 140 to 180 Wh/km in practice, which makes daily consumption significantly higher than theoretical figures suggest.

Why both matter: the 16 kWh per 100 km figure is a typical-cycle baseline. If your car is closer to 170 Wh/km, that same 100 km is closer to 17 kWh. Plan for the higher figure when sizing an off-grid system, because short winter days and partial charging inefficiencies are not going to help you.

Specs and Requirements at a Glance

Off-grid system rule of thumb: a Level 2 charger running at 7 kW for four hours overnight to add ~120 km of range pulls 28 kWh. That alone is more than half the daily consumption of a typical efficient Australian household before you count lights, fridge, and air conditioning.

What This Means for the Off-Grid System

Off-grid EV charging requires both generation (PV) and storage sized upward of a typical house-only off-grid system. The standard 6.6 kW solar array and 10–13 kWh battery bank that comfortably runs a house will not comfortably run a house and charge a BEV.

Key design points:

• Continuous inverter rating matters more than peak rating. Charging a car at 7 kW for several hours is a sustained load, not a surge. Check the continuous rating, not the 5-minute peak. An inverter rated "10 kW peak / 5 kW continuous" is not a 10 kW charger-compatible inverter.
• Battery capacity has to cover overnight charging if there is no generator backup. If you want the car charged by morning without a diesel block, your battery bank needs to absorb the daytime solar and discharge it through the evening charge session.
• DC-coupled EV battery bank architecture is one valid approach. Isolating the EV charging loop from the house battery loop can extend house battery life by avoiding deep cycles driven by the car. It is not the only valid architecture, but it is a sound one when the EV is charged nightly.
• Generator backup becomes near-essential for BEVs in winter. Short solar days plus cloudy stretches plus a 60–80 kWh EV battery is a tough ask from solar alone. Most working off-grid EV owners run a generator as the safety net.

One colourful aside: there is a fantasy online where a single 5 kW inverter and a 10 kWh battery "happily charge an EV." They do not. They charge a small PHEV slowly while the house goes dark. Run the maths.

When to Call a Licensed Professional

This is not the place to save a few hundred dollars and learn the hard way.

• Any AC Level 2 circuit (7–22 kW): requires a licensed electrician. In Australia, the dedicated EV charger circuit and socket must be installed to AS/NZS 3000 wiring rules by a sparky who can issue a Certificate of Compliance for Electrical Work.
• Three-phase upgrades for 22 kW Level 2: definitely a sparky, and likely a network operator notification if your property has any grid interaction (even a grid-tie with battery backup).
• DC fast-charging (Level 3) equipment: call a licensed electrical contractor with commercial EV experience. This is industrial kit, not a weekend install.
• Inverter and battery sizing changes driven by EV load: a designer/installer with off-grid experience should re-model the system. Adding an EV to an existing off-grid system is a meaningful change, not an afterthought.
• Anything involving the main switchboard upgrade or new circuit protection: licensed electrician, full stop.

If your only electrical work is a 12 V DC accessory, you can DIY. Anything beyond that: pick up the phone.

Operating Notes for Off-Grid EV Use

• Charge to 80 % on DC fast-chargers (Transport for NSW). This applies to public fast-chargers. For daily home Level 2 charging, many owners run to 80 % as well to preserve battery life, but check the manufacturer's recommendation.
• Time-of-use (ToU) tariffs help if you have any grid connection. On a 15 c/kWh ToU rate, EV charging costs about $2.40 for 100 km of range (Solar Quotes). Off-grid, your "fuel cost" is the amortised cost of panels, batteries, and generator fuel, which can be lower or higher depending on your system age.
• Flat-rate home tariff comparison: at 21 c/kWh, charging costs about $3.36 for 100 km versus roughly $14 for a petrol car at $1.40 per litre (Solar Quotes). Off-grid electricity has no tariff, but it still has a real cost per kWh from hardware amortisation and generator wear.
• PHEV versus BEV off-grid: a Plug-in Hybrid Electric Vehicle (PHEV) with a shorter electric-only range than a BEV but more flexibility (Elite Power Group) is far less demanding on an off-grid system. If you want to dip into EV driving without doubling your solar array, a PHEV is the rational starting point. A Battery Electric Vehicle (BEV) with longer range but bigger battery needs the full upgrade.

FAQ

Can I charge an EV from a standard 10 A power point off-grid?

Yes. Level 1 charging at 1.4–2.4 kW works off any properly wired 230 V outlet fed by your off-grid system (Transport for NSW; Elite Power Group). It is slow, adding 10–20 km of range per hour, which suits a PHEV or a BEV driver who only tops up overnight.

How many solar panels do I need to charge an EV off-grid?

Rough working figure: every 100 km of EV driving needs around 16–17 kWh of charge. Allowing for inverter and charge losses, plan on roughly 20 kWh of solar generation per 100 km of daily driving. That is on top of household loads and accounting for winter sun angle and shorter days.

Do I need a three-phase off-grid system to charge an EV?

No. A single-phase 7 kW Level 2 charger is the practical off-grid ceiling and runs fine on single-phase. Three-phase only matters if you specifically want 22 kW AC charging, which is unusual off-grid.

What is the best plug standard to install for an off-grid setup today?

Type 2 (Mennekes) for AC. CCS2 if you are installing any DC fast-charging equipment, since CCS2 is the standard for new EVs in Australia (Transport for NSW).

Will my existing off-grid inverter handle a 7 kW EV charger?

Only if its continuous rating is 7 kW or more. Peak ratings are misleading for sustained EV charging loads. Many residential inverters rated "5 kW continuous" will throttle or fault on a multi-hour 7 kW EV charging session.

Is CHAdeMO still relevant?

For new installations in Australia, no. CCS2 is the dominant DC plug type in Australia (Transport for NSW). CHAdeMO is being phased out of new model line-ups. If you are specifying a DC fast-charger today, CCS2 is the correct standard.

Sources

• https://www.transport.nsw.gov.au/projects/current-projects/electric-vehicles/charging-an-electric-vehicle
• https://www.solarquotes.com.au/electric-vehicles/ev-charging-guide/
• https://www.elitepowergroup.com.au/news/learning-centre/learn-electric-vehicle-ev-charging-chargers-australia/