Why Aren’t Solar Powered Electric Cars More Popular?

By April 16, 2020 Blog
A person wraps their hand around the sun using camera perspective.

A person wraps their hand around the sun using camera perspective.

Today in the EV Connect Blog we’re looking at solar powered electric cars and asking the question: Why aren’t they more popular? We’re seeing more solar power plants and solar rooftop panels all the time. So why not solar powered electric vehicles?

The answer to this question is actually a fascinating insight into why traditional plug-in electric cars offer such a good value proposition, and why plug-in EVs are finally gaining serious market share after false starts in the past.

Why Haven’t We Gone Solar Already?

Why don’t we have solar powered electric cars yet? We had a good opportunity:

In the 1970s, there was an energy crisis: Oil-producing countries got into a major dispute with the United States. As a result, gasoline prices nearly doubled, and there were even shortages and rationing. That’s also how we got the now-defunct national speed limit of 55 miles per hour.

During the crisis, clever entrepreneurs built a generation of new electric vehicles to appeal to customers who didn’t want to spend so much money filling up the tank. These cars were crude by today’s standards: Most of them were almost cartoonishly small, not to mention flimsy and quite limited in weight capacity and operating range. They only ever caught on as a niche product.

They were plug-ins, just like today’s EVs. A few of these cars actually did have solar panels, but none of them were true, fully solar powered electric vehicles. So the question is: Why not?

Energy Density Is the Key Problem with Solar Cars

The biggest challenge facing solar powered electric cars is the problem of energy density. Traditional fuels like gasoline are very “energy dense,” meaning they store a lot of energy in a small amount of space.

Traditional fuels have to be able to do this, because cars consume hundreds or even thousands of times more power than, say, your laptop computer or an LED light bulb. Cars are very heavy and get even heavier with passengers and cargo. They also need to accelerate quickly, and sustain high speeds. And sometimes they have to do all of this while climbing up a steep hill.

Just as you can’t feed a lumberjack or an Olympic athlete with celery alone, you can’t run an electric car on solar power alone. It just doesn’t work. That’s why we don’t have solar powered electric vehicles already.

  • Trivia: Today’s electric car batteries are pretty energy-dense too, but they don’t come anywhere near the energy density of gasoline. In fact, gasoline is about 100 times more energy dense than a modern lithium-ion battery.

A Problem of Space: Why Solar Power Electric Cars Don’t Work the Way You Want

Solar power generation takes up a lot of space. That’s a direct consequence of the low energy density of solar radiation. If you’ve ever installed solar lights around your sidewalk and lawn, you know how unimpressive they can be. Just imagine trying to run a solar powered electric car!

For example, the Nissan LEAF EV motor can operate at up to 80 kilowatts. If you were to use no battery, and run the motor directly off of solar panels, you would need about 15 houses worth of rooftop solar panels to generate that much electricity. And that’s assuming full sunshine!

What About Batteries?

Of course, solar power electric cars don’t run on solar power directly. They run on batteries, just like regular plug-in EVs do. But then the question becomes: “How long does it take to charge the batteries using solar power?”

The answer to this is that it takes a very long time, especially when you consider the fact that the sun isn’t always shining. You can’t charge a solar power electric car “overnight” the way you can a traditional EV. And you can’t park in a garage or under a tree.

What this means is that solar power is not viable as the primary source of energy for an electric vehicle—and it never will be, because it physically can’t be.

The Trade-Offs of Solar Powered Electric Vehicles

A bubble-top solar power electric car.

However, solar EVs do exist! That’s right: We actually do have solar power electric cars already. We just don’t have very many of them, and it turns out there’s a good reason for that:

When it comes to the question of how these cars get around this energy density problem, the short answer is “major trade-offs.” There are two basic types of solar car, based on two different kinds of trade-offs:

  • Solar “Boosted” EVs: These are not true solar power electric cars. They are traditional EVs with solar panels on the roof. You still have to plug them in for most of your charging needs. An example is the Sion, by Sono Motors. To fully charge the battery of a solar-boosted car using solar power alone would take hours, sometimes days, in the sunshine. Therefore, in practical terms, either you would have to wait a long time between drives, or drive only short distances, or rely on plug-in power as your main energy source. Most of the time, the latter one is what ends up happening, with the solar power component being reduced to a mere “efficiency boost” that slightly offsets the cost of running the car’s electronics.
  • True Solar EVs: Solar power electric cars that use solar energy as the main energy source are extremely rare, though they do exist. But to make them work you have to accept a whole different set of major trade-offs. With solar power, we’re talking about having less power to run a car than you would need to run a dishwasher at home. So true solar powered electric vehicles tend to be very tiny and very slow, with small operating ranges and low weight limits. They’re closer in performance capability to golf carts than to traditional highway-safe automobiles.

What Does the Future Hold in Store for Solar Power Electric Cars?

While solar technology itself is a highly promising and increasingly important component of our national energy infrastructure, it takes a lot of space to work: rooftop panels and large solar power plants. That’s why, sadly, solar powered electric vehicles are never going to be viable as a replacement for most people’s transportation needs. Cars are just too big, too fast, and require too much energy, for solar power to work.

However, we will continue to see solar power electric cars on the fringes: At EV Connect we expect solar boosting to become a selling point on many higher-end EVs. The efficiency gains from solar assistance are potentially very real. The integrated solar panels look good. And many people are excited about going solar and want to “wear” their values. What better way than having solar panels on the roof of your car?

We’ll also continue to see a small number of true solar powered electric cars serving as light transportation alternatives to bicycles, golf carts, and scooters. These EVs may have some extra appeal with the younger generations, who are increasingly priced out of traditional car ownership and do not embrace car ownership as part of the quintessential American experience the way previous generations did.

What Solar Power Electric Cars Can Teach Us About Plug-Ins

There’s an important lesson we can learn from the fact that solar powered electric vehicles are not viable replacements for most cars: The problem that fundamentally holds back solar power electric cars is energy density, especially in terms of:

  • How long it takes to charge up
  • How big of an operating range you have
  • How much weight the car can carry
  • How much speed and performance it offers

An EV sits parked, plugged in, and charging.

For plug-in EVs, all of these problems were solved in the 2010s:

  • We have Level 2 chargers that can top off a car in an hour or two, and DC fast chargers that can charge a battery from zero to 80 percent in less than half an hour.
  • Operating ranges are now well into the 200s miles on many models, which meets all local transportation needs and most long-distance needs. The deployment of additional charging infrastructure means that there are very few EV “dead zones” left in the country. Basically, you can drive an EV almost anywhere in the lower 48 states and Hawaii.
  • Today’s EVs are comparable to or better than traditional automobiles in cargo capacity, and weight limits.
  • Most EVs offer superior acceleration compared to gas-powered vehicles. In terms of top speed, virtually all EVs can do at least 65 mph, and some can go even faster, all the way up to those brutal 80 mph speed limits in Texas and a few other places.

Simply put, while solar power electric cars remain a pipe dream, plug-in electric cars are legitimate substitutes for most people in most circumstances. The market is still working on developing good EV pickup trucks, but in terms of passenger sedans and SUVs, we are already there.

Take Advantage of the Opportunity to Install Your Own EV Charging Infrastructure

Solar powered electric vehicles may never become a thing, but electric vehicles as a whole are here to stay. The nation is going to need a lot more EV charging infrastructure in the next few years. EV sales are projected to grow strongly throughout the 2020s, and we’ll need the charging stations to meet that growing demand. That’s why so many federal and state incentives for new charging infrastructure are available.

It makes a lot of sense right now to consider installing EV charging stations on your parking lots:

  • Provide EV charging for customers, employees and residents.
  • Grow ROI on your parking lots by providing monetized EV charging to the general public.
  • Convert your corporate or municipal vehicle fleet to electric to save on maintenance and help meet zero-emissions goals.

At EV Connect we offer professional charging solutions for your EV charging units, so that you can network them together from a single point and easily manage and monitor usage, spot maintenance issues, adjust prices, and more.

Our EV Cloud Platform goes even farther, giving you the means to custom brand your charging networks, achieve system optimizations, and connect your drivers with charging stations across the country.

Contact us at EV Connect today to learn how we can help install and manage EV chargers at your parking lots. And don’t forget to visit the EV Connect Blog homepage to see more articles like this on a wide variety of topics in the EV industry!

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