Putting Solar Panels on Your EV Won't Make It Free

I'm not sure why we are getting a story about the ability (or lack thereof) of solar to charge an EV battery, from a website that is mostly about entertainment technology, but I guess EVs are popular with the theater kids. From 3DVF: They thought solar panels would boost their electric car’s autonomy, but reality proves disappointing

Now don't get me wrong, with the right inverter, and several acres of solar panels, properly positioned, you could recharge your EV battery, or any other battery. If you limit yourself to solar panels you can put on a car, you won't be able to do much.

But believing that you can power an EV with the amount of solar panels you can deploy in that much space, is apparently something that the average theater kid believes.

Take the Hyundai Ioniq 5, for example. It sips energy at 17 kWh per 100 km, yet roof panels would need roughly 28 hours of peak sun to add about 80 km (a best-case calculation often floated by accessory makers like Solarstic). In real life, you may net closer to 15 km on a bright day.

The reason is simple: power. These systems typically max out near 1.2 kW under perfect alignment and temperature. That’s minuscule next to home charging or public DC points—on the order of 40x weaker than a modest 50 kW roadside charger. A full battery purely from rooftop solar would take days, not hours.

Here is a bit of the fine print, that doesn't get advertised when you buy solar panels. The rating for wattage is measure when the panel temperature is about 60 degrees Fahrenheit. Not the air temperature, but the panel temperature. These panels are typically black or dark blue, behind a protective coating. For every degree above 60, the efficiency - the power output - of the panel decreases. In anything but winter weather the panel temperature will be elevated. Think of putting your hand on a black car on a sunny August afternoon.

Another problem is shade. Depending on the type of panel you have, a small amount of shade on the panel, even a few percent, can significantly degrade the power output of the panel. I'm sure they've gotten better at this, but there is a reason that you install solar panels where there are no trees, and you keep them clean.

This is the MGUY Australia video The sheer STUPIDITY of "SOLAR cars"

I despair for the future of humanity if this is the level of scientific understanding that our education system is churning out.

I don't know if the EV car companies actually believed that they could achieve any level of charging by putting solar panels on a car, or if they just knew that most of the EV-car-buying public would be ignorant of the basic reality of the amount of solar panels required to get any noticeable charge.

The video is about 11 minutes.