How much energy an EV adds
EVs typically go about three to four miles per kilowatt-hour, less in Colorado winters when cabin heat and cold batteries cut efficiency, and less at highway speeds up I-70. A driver covering 1,000 miles a month might add roughly 250–350 kWh. Your car’s app will tell you your real number after a month or two.
How many extra panels that takes depends on your roof’s orientation, tilt and shading, and on your town — Colorado’s sunshine is strong, but a shaded foothills roof and an open plains roof produce very different amounts per panel. For a typical commuter it’s usually a few kilowatts of added capacity. We model your actual roof with location-specific production data rather than using a statewide average.
You don’t have to charge at noon
Under 1:1 net metering, which Xcel generally uses, a kilowatt-hour exported at noon offsets one you buy at midnight. So you can charge overnight when you’re home and still be “charging on solar” in bill terms.
Timing does matter on time-of-use: charging between 5 and 9 pm on weekdays is the most expensive choice on Xcel’s plan. Set the car or charger to start after 9 pm. In utilities that credit exports below retail — Longmont for newer systems, or Fort Collins at time-of-day rates — charging while the sun is up, on weekends or from a battery, captures more value.
The charger
A Level 2 charger installation typically runs about $2,500–$3,000 with us, depending on the distance from your panel and whether the panel has room. We install Tesla Wall Connectors, Enphase IQ EV Chargers and SigEnergy’s bidirectional DC charger. If your panel is only 100 amps, load management or a panel upgrade may be needed.
The federal §30C charger credit ended for equipment placed in service after June 30, 2026. Xcel has offered an EV wiring rebate tied to enrolling in its charging program; check Xcel’s current terms before you count on it.
Gas versus grid versus solar
Per mile, off-peak grid charging already costs well under gasoline for most drivers, and solar-offset charging costs less again once the system is paid for. Our EV fuel-cost calculator compares the three using your car and your miles.
FAQ
Questions we hear
How many solar panels does it take to charge an EV?
For a typical commuter, usually a few kilowatts of added capacity — a handful of modern panels — offsets a year of charging. High-mileage drivers, big trucks and winter-heavy driving need more. We size from your actual miles, your car’s efficiency and your roof’s modeled production.
Do I need a battery to charge my EV with solar?
Not under 1:1 net metering; your daytime credits cover overnight charging. A battery helps in utilities that credit exports below retail, or if you want to avoid the on-peak window while still charging in the evening.
Is there still a federal tax credit for home EV chargers?
No. The §30C credit ended for chargers placed in service after June 30, 2026. As of September 2026, check Xcel and your city for any local charger or wiring rebates.
When should I charge my EV on Xcel’s time-of-use plan?
Anytime outside 5–9 pm on non-holiday weekdays; overnight is the common choice. Most EVs and chargers let you schedule the start time.
Will adding an EV change the size of solar I should buy?
Yes, if you plan to buy one in the next few years, size for it now — adding panels later means a second permit and interconnection. Colorado net metering allows systems sized to expected consumption, and a planned EV is part of that.