EV Charging and Solar: Can You Power Your Electric Car from Your Rooftop?

Electric vehicles are arriving in rural Queensland in growing numbers. And the question we're hearing more often is a sensible one: if I'm investing in solar, can I use it to charge my car?

The short answer is yes. And when you do the numbers, it changes the economics of both the solar system and the vehicle significantly.

How Much Electricity Does an EV Actually Use?

A typical electric vehicle consumes roughly 15–20kWh per 100 kilometres, depending on the model, drivetrain, and driving conditions (efficient sedans can sit closer to 12kWh/100km; larger SUVs and AWD models can run higher).

For average Australian driving around 13,000km per year per the ABS Survey of Motor Vehicle Use that's approximately 1,950–2,600kWh of electricity annually, roughly equivalent to adding one or two extra people to your household's energy consumption. Rural drivers covering longer distances for work or town trips will naturally use more than this.

What Does That Actually Cost and Save?

Charging method	Annual cost (13,000km, 8L/100km petrol equivalent)
Petrol (regional QLD average ~$1.85–$1.90/L)	~$1,900–$2,000
Grid electricity (standard rate, 28–33c/kWh)	~$550–$860
Grid electricity (off-peak rate, if available)	~$400–$550
Home solar (self-consumption, daytime charging)	Near zero marginal cost

Petrol pricing is current as of publishing and fluctuates regularly check current regional QLD prices before relying on this comparison for a purchase decision.

The gap between petrol and grid charging is already significant. The gap between petrol and solar charging is the real prize and it's the difference between an EV that saves you money and one that just moves the expense from the bowser to your power bill.

What Size Solar System Do You Need If You Also Have an EV?

Household setup	Typical system size
Standard household, 2 peple no EV	6.6kW
Household + one EV	10kW
Household + EV + battery (charge overnight from stored solar)	10kW + 10–13.5kWh battery
Farm/commercial + EV fleet or heavy daytime loads	Sized individually from load data

EV charging is inherently solar-friendly it's a daytime activity if you set it up that way. Smart EV chargers can be programmed to charge only when your solar system is producing surplus power, redirecting what would otherwise be exported to the grid (at 8.66 cents on the Ergon network) into your car's battery at zero marginal cost.

How Does a Smart EV Charger Work With Solar?

Modern smart EV chargers connect to your home's energy management system and detect when your solar panels are generating more than your house is consuming. Rather than exporting that surplus to the grid for a low feed-in tariff, the charger diverts it directly into your vehicle.

This is often called "solar-only mode" or "eco mode," and it's particularly valuable for homeowners where the feed-in tariff is low like Ergon Energy customers in regional Queensland, where the current export rate is 8 cents versus 28–33 cents for grid power you'd otherwise buy.

A few practical things to check before you commit to a charger:

• Does your property have single-phase or three-phase power? Faster chargers (7kW+) often require three-phase worth confirming before you budget for one.

• Is your switchboard and meter set up to support EV charger installation, or will it need an upgrade?

• Does the charger you're considering integrate with your specific inverter/monitoring brand for true solar-tracking (not all do out of the box)?

We check all of this as part of sizing your system, so you're not caught out after the fact.

What About Rural Properties That Drive More?

This is where the numbers get particularly compelling for our customers in outback Queensland. Longer distances, higher fuel bills, and fewer public charging stations mean home solar charging is the backbone of an EV strategy for regional properties not a nice-to-have. Charging at home from your own solar covers daily needs; fast chargers in regional towns handle longer runs.

For rural Queensland homeowners sizing a solar system for the first time, factoring in an EV circuit during the initial installation is much cheaper than retrofitting it later running new cabling and upgrading a switchboard after the fact typically costs more than including it in the original design.

Current Incentives

At the federal level, the Cheaper Home Batteries Program (from 1 July 2025) applies to home battery systems, which can complement solar and EV charging by storing daytime generation for overnight vehicle charging. The rebate covers approximately 30% of eligible battery costs (systems from 5–100kWh).

Standard STC rebates also apply to the solar panels and hybrid inverter portion of your system, typically worth $1,500–$3,000 upfront on a residential system, separate from any battery rebate.

Frequently Asked Questions

Can I charge an EV overnight from solar if I don't have a battery? No without a battery, solar only charges your car while the sun is producing more than your house is using. Overnight charging without a battery draws from the grid at your normal rate.

Do I need to upgrade my switchboard for an EV charger? Sometimes. It depends on your existing setup and the charger's power rating. We assess this at quote stage so there are no surprises.

Will charging my EV affect my solar system's warranty or performance? No a correctly installed smart charger works alongside your solar system without affecting panel or inverter warranties.

Is vehicle-to-home (V2H) technology available yet? It's emerging but not yet mainstream or widely supported by Australian inverters and EV models. If it's important to you, ask us about current compatibility before you commit to a specific EV or inverter brand.

Should I size my system for the EV I have now, or plan for a second one later? If you're likely to add a second EV or upgrade within the system's ~20–25 year lifespan, it's worth discussing headroom now; oversizing slightly upfront is usually cheaper than a second installation later.

📞 Planning an EV or want to future-proof your solar system for one? Let's design it right from the start. Call William on 0431 999 284 or visit www.qldoutbacksolar.com

All facts in this post are sourced from the following authoritative sources. We recommend bookmarking these for ongoing updates government rebate details, tariff rates, and fuel prices change regularly.

1. Department of Climate Change, Energy, the Environment and Water — Electric vehicles https://www.dcceew.gov.au/energy/transport/electric-vehicles Official federal government information on EVs in Australia, incentives, and the broader clean transport strategy.

2. Queensland Government — Electric vehicles and charging https://www.qld.gov.au/transport/projects/electricvehicles Queensland Government EV page including current state-level rebate and charging infrastructure programs.

3. Federal Government — Cheaper Home Batteries Program https://www.dcceew.gov.au/energy/programs/cheaper-home-batteries Battery rebate details. Relevant for EV owners who want to store solar for overnight vehicle charging.

4. Australian Bureau of Statistics — Survey of Motor Vehicle Use, Australia https://www.abs.gov.au/statistics/industry/tourism-and-transport/survey-motor-vehicle-use-australia/latest-release Official source for average annual kilometres driven by Australian vehicles.

5. Queensland Competition Authority — Solar feed-in tariff (Ergon network) https://www.qca.org.au/project/solar-feed-in-tariff/ Official source for the regulated Ergon Energy feed-in tariff used in the cost comparisons above.

6. Australian Government — Energy.gov.au — Electric vehicles and solar https://www.energy.gov.au/households/solar-and-batteries/electric-vehicles Federal government overview of combining home solar with EV charging, including smart charger guidance.