How Many Solar Panels Do You Need to Charge an EV at Home?

If you are wondering how many solar panels you need to charge an EV at home, the short answer for most Sydney households is:

around 5 to 10 extra solar panels for average EV driving, depending on how far you drive, how efficient your EV is, the size of your panels, and when you charge.

That is because 1 kW of solar panels in Australia typically generates about 3.5 to 5 kWh per day on average, depending on location and system design. The Australian Government also says Australian homes typically use 11 to 23 kWh per day, so adding EV charging can materially change how large your solar system should be.

For many EV owners, the real answer is not just “how many panels?” but:

How many extra solar panels do I need on top of my normal household usage to charge my EV at home without relying heavily on the grid?

For a typical EV in Australia, a useful starting point is:

• Light driving: 4 to 6 extra solar panels

• Average driving: 5 to 8 extra solar panels

• Heavy driving: 8 to 12+ extra solar panels

That estimate is based on:

• a typical EV efficiency of about 17 kWh per 100 km

• average annual driving of about 14,000 km

• modern panels in the roughly 400–440W range

• Sydney-level solar production conditions being broadly strong compared with much of Australia.

Using the Electric Vehicle Council’s ballpark figure of 14,000 km per year and 17 kWh/100 km, a typical EV uses about 2,400 kWh per year, or roughly 6.6 kWh per day.

That extra daily load is exactly why so many Sydney homeowners with older 5 kW systems start looking at upgrades once they buy an EV.

The simple formula is:

Daily EV charging need in kWh ÷ average daily energy output per panel = number of panels needed

Example:

If your EV needs about 6.6 kWh per day and each panel produces around 1.5 to 2.2 kWh per day depending on panel size, sunlight, orientation and system losses, you might need roughly:

3 to 5 panels in ideal conditions
or more realistically
5 to 8 panels once real-world household usage, weather, charging times and export losses are considered.

That is why most real-world solar + EV system designs land higher than the “perfect maths” answer.

According to the Electric Vehicle Council, a typical EV driver travelling around 14,000 km per year at 17 kWh per 100 km will use around 2,400 kWh per year. That works out to about:

• 200 kWh per month

• 46 kWh per week

• 6.6 kWh per day on average.

The Electric Vehicle Council has also cited home charging assumptions of roughly 10 kWh per day in some grid impact modelling, which shows how much this can vary depending on the vehicle and driving habits.

So if you are asking how many solar panels to charge an EV at home, you first need to know how much electricity your EV is actually likely to use.

If you drive lightly

If you only do school runs, local errands and occasional commutes, your EV may need closer to 4 to 5 kWh per day. In that case, around 4 to 6 extra panels may be enough in a well-designed Sydney solar system. This is an estimate based on typical Australian solar production of 3.5 to 5 kWh per day per 1 kW of panels.

If you drive an average amount

For the average EV owner, 5 to 8 extra panels is often the sweet spot. That usually covers a meaningful chunk of EV charging without requiring a major system oversize. The average EV usage estimate above is based on the Electric Vehicle Council’s typical annual distance and efficiency figures.

If you drive a lot

If you have a long commute, multiple school pickups, weekend travel or a larger EV with higher consumption, you may need 8 to 12 or more extra panels. For these households, a larger solar system and possibly a battery often makes more sense than trying to squeeze EV charging into a smaller existing system.

The exact answer depends on the model, how far it is driven, and whether you want to cover just EV charging or your whole home as well.

A good practical answer is:

• for average Tesla driving, 5 to 8 extra modern solar panels is often a reasonable planning estimate

• for heavier daily driving, 8 to 12+ extra panels may be more realistic

This is because Tesla charging at home is still just electricity use measured in kWh. The solar system does not care whether the vehicle is a Tesla, BYD, Kia EV, Polestar or another EV, it only cares how much energy the car uses and when you charge it.

This depends on how empty the battery is and the size of the battery pack, but for day-to-day home charging, most people are not charging from 0% to 100% every day.

Instead, they are usually replacing the energy used from normal daily driving.

That is why the most useful planning number is often the daily average, not the full battery size. For many households, that daily energy replacement is roughly 6 to 10 kWh per day.

Often yes, but it depends on what else your home uses during the day.

A typical 6.6 kW solar system in Sydney can produce roughly 25.7 kWh per day on average according to Solar Calculator’s Sydney estimates, while a 5 kW system can produce around 19.6 kWh per day. The Australian Government separately notes that 1 kW of solar in Australia may produce around 3.5 to 5 kWh per day on average.

That means a 6.6 kW system can often support average EV charging if:

• daytime household consumption is moderate

• the car is charged during solar production hours

• the roof has good solar orientation

• the system is not heavily shaded

But if your household already uses a lot of daytime power, air conditioning, pool pumps, electric hot water, home office loads, or multiple appliances, the EV may push you beyond what that system can comfortably offset.

The average size of new rooftop solar systems in Australia has continued to grow, reaching 9.98 kW in 2024, up from 9.41 kW in 2023, according to the Clean Energy Council.

That trend matters because many older home solar systems were sized for:

• lights

• appliances

• maybe air conditioning

They were not sized for:

• EV charging

• batteries

• electrified hot water

• all-electric homes

So if you bought solar years ago and now own an EV, your system may not be “bad”,  it may just be undersized for how modern households use energy now.

From a solar savings perspective, charging during the day is usually best, because you are using your own solar directly instead of exporting it for a relatively low feed-in tariff and then buying power back later at a higher retail rate.

IPART’s benchmark all-day solar feed-in tariff range for NSW for 2025–26 is 4.8 to 7.3 c/kWh, which is far below what most households pay for imported electricity. That is why self-consuming your solar is generally more valuable than exporting it.

So if your goal is to charge your EV as cheaply as possible with solar, the best setup is often:

• enough solar panels

• daytime charging where possible

• smart charger controls

• optionally a battery if you want more flexibility

No, not necessarily. You can absolutely charge an EV from solar without a battery if:

• the car is home during the day

• you can schedule charging during solar production hours

• your solar system is large enough

A battery becomes more useful if:

• the EV is usually only home at night

• you want backup power benefits too

• your household already has high evening demand

• you want to store excess solar instead of exporting it cheaply to the grid

For many Sydney households, the best value move is:

1. size the solar system properly first

2. then decide whether a battery adds enough extra value

here is no one-size-fits-all answer, but as a rough guide:

Small households with one EV

A 6.6 kW to 8 kW system may be enough if driving is moderate and daytime home loads are manageable.

Family households with one EV

An 8 kW to 10 kW+ system is often more comfortable, especially if the home also runs air conditioning or electric hot water.

Larger all-electric homes or heavy EV users

A 10 kW+ solar system, and sometimes a battery, is often the smarter long-term choice.

This lines up with the broader market trend toward larger systems, with the national average new rooftop system size reaching nearly 10 kW in 2024.

If you already have solar and are now buying an EV, ask these questions:

• How many kWh does my home already use each day?

• How much spare daytime solar generation do I usually export?

• Is my current system already maxed out?

• Can I add more panels to the existing inverter?

• Do I need a new inverter or battery-ready setup?

• Will I mainly charge during the day or at night?

In many homes, the most cost-effective solution is not starting again, it is expanding or redesigning the system around EV charging.

The best solar system for EV charging is not based on a generic online estimate. It should be sized around:

• your current electricity usage

• your EV driving distance

• your EV efficiency

• whether you charge mostly during the day or at night

• roof space and orientation

• whether you plan to add a battery later

• whether you may add a second EV in future

That is the difference between a system that looks good on paper and one that actually cuts bills.

For most Sydney households, a practical estimate is:

around 5 to 10 extra solar panels for average EV charging, with higher-use drivers often needing more.

If you already have solar, the better question is often:

Do I have enough spare solar generation to cover EV charging, or do I need to upgrade my system?

Because once an EV enters the picture, your home’s electricity demand changes — and your solar system should be designed to match it.

If you are planning to buy an EV, already own one, or want to know whether your existing solar system is large enough, MPV Solar can help you work out:

• how many solar panels you actually need

• whether your current system can support EV charging

• whether you should add a battery

• what system size makes sense for your home, driving habits and future plans

A good quote should not just tell you the panel count. It should show how your solar, EV charging and household usage work together.