An overwhelming majority of the world's estimated 1.4 billion vehicles run on fossil fuels, releasing a whole bunch of pollutants. Can you believe that a typical car emits roughly 4.6 metric tons of CO2 every year?
Fortunately, momentum to take gas vehicles off the road is building around the world with many countries planning to phase out fossil fuel powered vehicles in the coming years.
By now, we know all about the sun and the technology like the batteries, solar cells and aerodynamic structures that are being used to harness the sun's power. We even understand the mechanics of how to power a solar car. And don't worry, if you're fuzzy on the details here. So, now, let's explore what's it going to take to power all of our cars using the sun.
It all comes down to pretty much one thing. The amount of solar power that a car is able to generate compared to the amount of power it uses up. Electric cars, gas powered cars, self-driving cars, you name it, have pretty big power demands. So while incorporating solar technology into lightweight vehicles like e-bikes and drones is relatively easy, the same can't be said for larger vehicles like cars which can easily weigh at least 2,000 kilograms and need to be able to maintain constant power at high speeds. Plus, most commercial cars today are also outfitted with power draining AC units, radio systems and complex computer circuits.
This poses a bit of a problem for photovoltaic systems, which as we've learned in previous articles, are by their very nature only as powerful as the amount of photons they're able to absorb. The more photons a solar cell absorbs into its material, the more electricity can be produced. And basically, cars require a lot of energy to work. And if we want to power them with solar energy, there's not a whole lot of surface area to work with. And then there's the fact that the solar cells we use out in the real world today don't often reach their already limited efficiency.
Right now, the best research-grade solar cells are still at, like, 30%. And that's in a lab environment, like, a teeny tiny solar cell.
With that said, we've certainly made huge strides in improving the conversion rate of solar cells. And work is underway to push their potential even further, whether that's through finding new materials configurations, developing more sophisticated anti-reflective coatings to let the cells capture more light, or even figuring out how to manipulate light waves so that they're easier for the cells to absorb.
But until solar cells reach their maximum efficiency and then some, designing solar vehicles to be as aerodynamic lightweight and efficient as possible will remain the primary focus. So, while powering a car on sunlight alone does remain a challenge, it's certainly not impossible, because solar cars are a reality right now. I've been given a pretty unique opportunity to ride in a solar car while it is going around the figure eight track.
But solar cars aren't just at the Stanford Solar Car team's garage, or racing across the Outback at the World Solar Challenge. We've actually got a little known but rapidly growing solar vehicle commercial market. Startups like Sono Motors and Lightyear are going all-in on solar.
And what excites me the most about making commercial solar cars is showing to the world that we can be much more efficient with the energy that we have available without having to compromise on the convenience you get every day. You improve the aerodynamics a bit, you improve the weight a bit, you increase the solar panel array a bit, you increase the efficiency of the solar panel a bit, and then combining all of that, you basically match energy consumption and energy yield. We're not 100% there yet, but we're getting pretty close. The closer you get, the more practical the car becomes to use every day.
Established companies like Hyundai and Toyota are also developing ways to incorporate solar panels into their cars. Albeit mainly as a way to lend cars a few extra miles of range or power some of the auxiliary system. It's a little less ambitious, sure, but it's certainly a step in the right direction. And research teams all over the world are working tirelessly to make the next revolutionary breakthrough in solar panel technology, which could be exactly what our cars need to level up. There's just too much at stake here to let that big beautiful star above our heads go to waste.