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Why do electric cars not use solar panels?

It would seem a marriage made in heaven. Solar panels and electric cars. Thoughts of unlimited mileage. The reality is that solar panels do not produce enough power to properly charge an electric car unless your car happened to also be the size of an average house roof.

Some cars do however come with solar panel roofs. The extra energy it absorbs is usually used to run a cooling fan during the hot summer months to help keep the cabin cool when parked. It’s a wonderful feature, but a far cry from being able to charge up your depleted batteries after a long trip.

Even Tesla, a company that sells solar panel roofs and power walls doesn’t offer a solar panel roof on their car models.

That however is a wonderful system. A large array of panels collect the energy from the sun and store it in large battery packs for later use. Again though, that’s a large portion of a roof covered with panels to make an appreciable amount of power. If you are looking to get “off-grid” it’s a great start and depending on your driving could conceivably keep your car charged.

The caveat to that though is not everyone lives in California. Not everyone is blessed with year-round, daily sunshine to bask in. Some of us live in Canada, or England, or other exotic locals who have to suffer through winters and rain and clouds. Damn you clouds!

While even the everlasting sun of California would not be able to keep a solar roofs’ EV running non-stop, elsewhere it’s not even a consideration.

With current panels only converting about 20% of the energy it absorbs into usable power, a double or even triple efficacy increase still wouldn’t get you to the point where it would be enough to run an automobile.

Sadly, solar panel technology is just not at a point where it can generate a significant amount of electricity without a very large surface area. The dream of a car that can run forever, with nothing more than a little sunlight is sadly still a long way off.

Courtesy of I really, REALLY want this.

To throw some numbers at you. A one-square-foot solar panel generates about 10-15 watts of electricity/hour.

A typical car roof is about 12 square feet. About 120 to 180 watts of electricity. On average a Tesla Model 3 will use about 360 watts per mile.

So if you’re prepared to drive 0.5 miles per hour, on a sunny day, at noon. Then you my friend are golden.

Luckily for us, companies aren’t just accepting these hurdles. Hyundai for example is working on transparent panels that can be used on more areas of the cars. Others are working on Solar Paint. The actual paint can absorb the sun’s rays and convert it into electricity.

The possibility of a Solar/Electric or Gas hybrid is a real possibility. Either with an increase in range or an increase in power.

The sun is the most powerful thing in our little portion of the universe. As companies continue to work on exploiting that, technologies will improve, and new technologies will emerge.

In the meantime, keep that extension cord handy. You’re going to need it.