A sunny weekday can produce more electricity than many Australian homes use in the middle of the day. If your car is away at work, that surplus is often exported to the grid for a modest feed-in tariff. So, can solar charge electric cars? Yes. With the right solar system, EV charger and charging plan, your rooftop generation can cover a meaningful share, and sometimes most, of your driving energy.
The result is not free motoring in every season or for every driving pattern. It is a practical way to turn low-cost solar electricity into kilometres, reduce reliance on grid power and make better use of an energy system you already own.
Can solar charge electric cars during the day?
Yes. Solar panels generate direct current electricity, which is converted by your solar inverter and supplied through your switchboard. When an EV charger is connected to the property, it can use that solar power alongside any available grid electricity.
In simple terms, your home uses solar generation first. Any extra solar can be directed to your EV while it is plugged in. If the car needs more power than the panels are producing, the balance comes from the grid unless your charger is configured to limit charging to surplus solar.
This matters because a standard home EV charger may draw 7 kW, while a typical residential solar system may produce anywhere from very little on an overcast morning to well above 7 kW at its midday peak. Solar output changes constantly with weather, season, roof orientation and shading. A smart charging setup responds to those changes rather than assuming the sun will always meet the full charging load.
For households where the vehicle is parked at home during the day, solar charging is usually straightforward. It can be especially valuable for people who work from home, have flexible schedules, or own a second vehicle that sits in the driveway for long periods.
How much solar power does an EV need?
The answer depends on how far you drive, how efficient the vehicle is and when you charge. Most electric cars use roughly 15 to 20 kWh per 100 kilometres in real-world conditions. A 50 km daily commute could therefore require around 7.5 to 10 kWh of electricity.
A well-performing 6.6 kW solar system may generate an average of around 20 to 30 kWh per day across a year in many parts of Australia, although actual output varies by location and season. That does not mean all of it is available for the car. Your air conditioning, appliances, pool pump and hot water system may also be drawing power at the same time.
The best question is not simply, “How many panels do I need for an EV?” It is, “How much daytime solar surplus do I have after my home or business energy use?” An energy assessment can identify that pattern and help size solar, battery storage and EV charging equipment around it.
A practical charging example
Say your home exports 12 kWh of solar on an average weekday after household use. Charging your EV with that surplus could add approximately 60 to 80 kilometres of range, depending on the vehicle and driving conditions. Over a working week, that may cover a substantial portion of typical suburban driving without buying daytime electricity from the grid.
On rainy days, during winter, or after a longer trip, grid power may still be needed. That is normal. The goal is to increase solar self-consumption and reduce charging costs, not to promise that the grid will never be required.
The charger makes a real difference
A basic EV charger will safely charge your vehicle, but it may not know how much surplus solar is available. If it starts charging at full power when solar output is low, it can draw significant electricity from the grid.
A smart EV charger can improve the outcome by monitoring household consumption and solar generation. Depending on the model and system design, it may be set to charge only when there is excess solar, adjust the charging rate as clouds pass, or combine solar power with cheaper off-peak electricity when needed.
Solar-only charging is ideal when maximising self-generated energy is your priority. However, it can be slower and less predictable. If you need the car fully charged by morning, a scheduled overnight charge on an off-peak tariff may be the more reliable option. Many households use both approaches: solar charging for routine daytime top-ups and scheduled grid charging when certainty matters.
For businesses, smart charging can be even more valuable. Workplace chargers can be managed around daytime solar production, staff charging needs and peak demand. This helps businesses offer EV charging without unnecessarily increasing operating costs.
Do you need a battery to charge an EV with solar?
No. A home battery is not required for solar EV charging. If your car is plugged in while solar panels are generating, the charger can use solar electricity directly through the home’s electrical system.
A battery becomes useful when your driving and solar production do not line up. It can store surplus solar generated during the day for use later in the evening, including EV charging. It may also provide backup capability when designed with appropriate equipment, although backup performance and the circuits supported vary between systems.
There is a trade-off. EV batteries are much larger than most household batteries. A home battery can make a valuable contribution to evening charging, but it may not fully recharge a vehicle after a long drive. In many cases, it is more cost-effective to use solar directly during the day, then use an off-peak tariff for any remaining overnight charging requirement.
Battery storage is best considered as part of the whole property energy plan. It can support evening household loads, improve solar self-use, reduce grid imports and provide backup options, while also helping with EV charging. Whether it delivers strong value depends on your tariff, usage profile, solar export levels and energy goals.
Getting the system size right
Adding an EV changes a property’s electricity demand. A household that previously used 15 kWh per day may add another 8 to 15 kWh on days when the car is charged. For high-kilometre drivers, the increase can be much greater.
That does not automatically mean you need the largest available solar system. Roof space, network limits, your daytime consumption and future plans all matter. But it does mean an older or smaller solar system may no longer be sized for the way you live.
When planning an upgrade, consider the full electrification picture. A solar system that supports an EV today may also need to accommodate a heat pump hot water system, reverse-cycle air conditioning or a home battery tomorrow. Designing for those future loads can avoid unnecessary rework and help you get better long-term value from the installation.
Professional design also matters for electrical capacity, switchboard requirements, charger location, cable runs and compliance. A licensed installer can assess whether your property can safely support the charger you want and recommend the most suitable charging speed.
What about public charging and overnight charging?
Solar at home will not replace every form of charging. Public fast chargers remain useful for road trips, drivers without off-street parking and days when you need to travel further than usual. Overnight grid charging can also be the simplest option for people who are away from home during daylight hours.
The strongest savings often come from a mixed strategy. Use surplus solar whenever the car is home during the day. Use smart scheduling to access lower-cost off-peak electricity when solar is unavailable. Keep public charging for convenience and long-distance travel rather than relying on it for every kilometre.
This approach gives you flexibility without forcing your routine around the weather. It also lets you benefit from solar generation even if your EV charging pattern changes from week to week.
A smarter way to plan solar EV charging
Solar charging works best when solar panels, battery storage, household loads and the EV charger are planned together. An integrated design can show how much solar your property produces, when you use energy, how much you export and where the biggest savings opportunity sits.
SunLoop Energy can help homeowners and businesses assess those moving parts and build a compliant system around their actual energy needs, rather than treating the EV charger as a standalone addition. The right setup should be simple to use, dependable in daily life and ready for the next stage of your electrification plans.
If your car spends time at home or at your workplace while the sun is out, solar can turn that parked time into lower-cost driving. Start with your driving habits and energy profile, then choose equipment that makes the most of the power already landing on your roof.
