Solar + EV integration
Enter up to 4 vehicles, each electric or gas. Get a combined panel count sized around just the EVs in your household fleet.
How it works
Step 1
Only electric vehicles contribute to solar sizing, so mark gas vehicles correctly to avoid overestimating your needed panel count.
Step 2
Even similar vehicle classes can have meaningfully different EPA ratings, so avoid averaging and enter each one individually.
Step 3
If a gas vehicle might convert to electric later, check the future EV readiness sizing tool to add appropriate headroom now.
Solar panels offset electricity use, and a gas vehicle draws no electricity from the home's system regardless of how much it's driven, so it contributes nothing to the panel count calculation. This might seem obvious, but it's an easy detail to overlook when thinking through a household's total vehicle fleet, especially in a mixed household transitioning gradually toward electric vehicles.
Combining multiple vehicles into a single averaged efficiency figure can introduce meaningful error, since even vehicles within the same general class, like two different compact SUVs, can have EPA ratings that differ by 15% or more. Entering each vehicle's actual efficiency and driving pattern separately, as this tool requires, produces a more accurate combined total than any single blended estimate.
Many households transition to electric vehicles gradually rather than all at once, replacing one gas vehicle with an EV every few years as leases end or vehicles age out. If this describes your household's likely path, the future EV readiness sizing tool can help add appropriate solar headroom now for vehicles you expect to electrify later, rather than sizing only for your current EV count and needing a separate expansion each time.
A vehicle used only occasionally, like a weekend car or a backup vehicle, should have its daily mileage figure calculated from realistic weekly use divided across all 7 days, not from its peak single-day usage. Households also adding storage should check the oversizing for future battery calculator. This avoids overstating that vehicle's contribution to the combined annual energy total.
Once you have your combined panel count, check whether your roof or carport space can accommodate it using the usable roof area calculator, or move on to wiring cost planning if multiple vehicles will charge simultaneously. An EV charger and panels together are a big purchase. The loan payment calculator in our Financing section can help you compare loan and cash options for the combined cost.
Questions
Only the electric vehicles in the household contribute to solar sizing, since gas vehicles don't draw from the home's electrical system. A 3-vehicle household with 2 EVs and 1 gas truck, for example, sizes solar around just the 2 EVs' combined energy need, typically adding around 9 panels for a 30-mile and 15-mile daily commute pair.
Yes, even similar vehicle classes can have meaningfully different efficiency ratings, and combining them into one averaged figure can introduce error. Entering each vehicle's actual EPA rating separately, even if the numbers are close, gives a more accurate combined total.
Check the future EV readiness solar sizing tool to add appropriate headroom now for a planned future conversion, rather than sizing only for vehicles that are currently electric. Adding this capacity during the initial installation is typically more cost-effective than a separate expansion later.
Enter each vehicle's realistic average daily mileage across a full week, not just a peak usage day, for an accurate combined total. A vehicle driven only on weekends should use its weekly mileage divided by 7, not its weekend-only distance.
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