If you already drive an electric vehicle, or you're planning on buying one, you've probably wondered: how many solar panels would I need to charge it?
For many Alberta homeowners driving approximately 20,000 km per year, about 8 additional solar panels can generate enough electricity to offset the annual charging needs of a typical EV.
But don’t worry! We’re not just going to give you a random number without showing you where we got it from – keep reading!
1. The Simple Math: Solar Panels Needed to Charge an EV
The easiest way to estimate how many solar panels you'll need is to look at two numbers:
- How much energy your EV uses each year.
- How much electricity a solar panel produces each year.
A typical Albertan drives their car about 20,000 km per year, and a typical electric vehicle can drive 5 km per kWh. So, the annual charging energy required = 4,000 kWh.
20,000 km ÷ 5 km/kWh = 4,000 kWh per year
A modern 500W residential solar panel in Alberta can produce approximately 500 kWh per year. It could be 10-20% higher or lower, depending on roof orientation, shading, and other site-specific factors, but 500kWh is a reasonable average.
4,000 kWh ÷ 500 kWh per panel = 8 panels
Another way of looking at it is by calculating how many kilometers of driving can you get from each 500W panel? Using the same estimates but in a different way, the average EV range that a 500W solar panel will give you per year is = 2,500kms.
500kWh x 5km/kWh = 2,500kms per year
2. Real-World Examples: Solar Panels by EV Model
So, it takes around 8 x 500W solar panels to charge the average EV throughout a year. Can we get more specific? Sure! Not all EVs consume the same amount of energy. Vehicle size, weight, model, etc. can all affect efficiency. For 20,000 km of annual driving, here's what that could look like:
As you can see, a highly efficient crossover may only require a handful of additional modules, while a full-size electric truck will typically require a larger solar system. That’s no surprise - any truck will use more gas than a smaller vehicle. We’re just giving the solar equivalent!
3. Apart from the EV Itself, What Else Can Change How Many Solar Panels You'll Need
Several factors influence how many panels you'll actually need:
- Your annual driving distance
- The solar system design (roof orientation, shading)
- The solar panel wattage and production
- Charging location and frequency (do you also charge at work, or elsewhere)
This is one reason that it is important to get a reputable solar company to do a proper site assessment. Two homeowners with identical EVs may require different system sizes because their roofs, driving/charging habits, and electricity usage are different.
If you already have solar! Adding an EV can significantly increase your household electricity consumption. A system that previously offset all of your annual usage may suddenly appear to be underperforming simply because your home's energy demand has increased. If that's happening, our guide on Why Your Solar System May Not Be Offsetting Your Bill in Alberta, and How to Fix It can help explain what's going on and what your options are.
4. Should You Add Solar Now If You're Buying an EV Later?
I f you're considering solar today and an EV sometime in the next few years, my advice is simple: don’t wait on solar just because the EV purchase is still in the future. Labour, permitting, and material costs tend to increase over time, so moving forward now can help you start saving sooner while keeping future EV needs in mind.
But remember! in Alberta, your solar system must be designed around your current annual electricity consumption (read more here). That means you wouldn't be able to install the ~8 extra EV panels ahead of time if you do not have the EV yet, because the additional electricity usage has not shown up on your bill.
But a good solar designer should still plan for future expansion. We can plan additional roof space to fit a larger system in the future, we can make sure our cables are a larger size to fit future panels, and we’ll choose the correct inverter that can help facilitate a system expansion (microinverters!). These details are much easier to plan for at the beginning than to work around later.
When we design your solar system, we will ask you about future EV purchases, and we account for all these little details (and many more) when you’re telling us about any future plans with EVs, ACs, hot tubs or other big electrical loads.
5. Gas vs. Grid vs. Solar: What Does Charging Your EV Actually Cost?
One of the biggest advantages of pairing solar with an EV is that you're not just generating electricity for your home, you're generating transportation fuel from your own roof!
Annual savings from EV+Solar compared to a gasoline vehicle can range from approximately $1,600 to $3,100+ per year, depending on your driving habits, fuel costs, electricity rates, and vehicle choice. Hybrids sit somewhere in the middle between EVs and gasoline vehicles and, in a sense, offer the best of both worlds. So your expected operating costs / savings for a hybrid vehicle would fall somewhere between the two.
Of course, every homeowner's financial picture is different. Vehicle efficiency, annual mileage, utility rates, future electricity prices, and solar production assumptions all affect the final numbers. If you'd like to understand how those projections are calculated, have a look at Can I Trust the Financials in a Solar Proposal?
Depending on your electricity setup, programs like Alberta's SolarClub can also influence the financial returns that you receive from your solar production throughout the year. We cover that in detail in How Alberta's SolarClub Actually Works.
Conclusion
For many Alberta homeowners, charging an EV with solar requires approximately 8 dedicated panels (in addition to the panels offsetting their home’s consumption) to offset around 20,000 km of annual driving.
The exact number will depend on your vehicle, driving habits, roof characteristics, and overall household electricity usage, but the principle remains the same: solar and EVs are a natural fit – especially if you have the roof space for it.
You're already reducing fuel costs by going electric. Adding solar gives you the opportunity to generate that energy yourself, directly from your own roof.
Planning for an EV today or in the future?
Potential Solar designs systems around your long-term energy goals. Whether you're looking to offset an existing EV or future-proof your home for electrification, we'll help determine the right system size and design a solution tailored to your home. Let's build a solar system that's ready for where you're headed next!
