Sun. Some time in the next century, solar energy  might make a large contribution to energy needs.  

And today, the dream of using solar energy  to power transportation is pushing automotive  

technology to its limits. It was right around  late 2005 where I became obsessed with the very  

idea of this vehicle. By building a solar car,  you'll get this constraint that you're limited  

in the amount of energy you have. But building a  practical solar car--one that can actually compete  

with fossil fuel vehicles and today's EVs--has  never really seemed possible. Until now.

So it started out of my garage like lots of  Southern California companies do. Aptera  

was really started, based on obsession with efficiency.  

Yeah, so actually it all started back in 2012 when  the CEO of--of Lightyear  

gave me a call and then he told me, yeah we're  going to participate in the World Solar Challenge.  

For years now, these two have been driven to  build the world's first commercial solar-powered car.  

Yeah, so I'm Arjo van der Ham, co-founder and  chief technology officer at Lightyear. My name is  

Steve Fambro, and I'm the co-CEO of Aptera Motors.  What Aptera and Lightyear are working on could  

revolutionize the auto industry and transform  transportation. The Lightyear One is a solar  

powered family car. It has five seats. It has a  five square meter solar panel. Aptera is a solar  

electric vehicle that has solar cells on virtually  every square meter surface of the vehicle.  

Now, you may have already seen solar cars with  similar out-of-this-world designs before. But  

these vehicles aren't just attention-grabbing  concept cars or experimental solar racers built  

for competition. These cars are designed and  engineered for the everyday commute.  

Having the solar cells on the vehicle lets us park it  in the Sun and charge it while you're at work,  

while you're shopping, or whatever.  So, if you drive 12,000 miles per year, something like that like most people do.

you might never have to plug it in at  all. You might just drive to work and back,  

and the car pretty much stays full. You can drive  about 10,000 miles a year in the Bay Area on  

the power of the Sun. And I think the average  person in that area drives about 13,000 miles  

a year. That's already about 70% of the typical  usage. So while you can plug in to recharge these  

vehicles... you may well not have to. What excites  me the most about making a commercial solar car  

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 may be thinking - Do  

we need a commercial solar car? After all,  electric vehicles are more popular than ever,  

with THREE MILLION sold globally in 2020. That's  roughly a 40% increase from the previous year!  

Well, unfortunately, due to the lithium-ion  batteries that they rely on and the electric grids  

they use to recharge, turns out - these “zero  emission vehicles” may not be as sustainable as  

we need them to be. Another alternative is to have  a solar electric vehicle that reduces a nation's  

dependence on the grid, that uses the Sun, which  is 90 million miles away and works every day.  

So, how are these two automakers able to use  solar as their car's primary power source?  

According to Arjo, it comes down to  balancing a fundamental equation. Yeah, so basically  

it's the amount of energy you consume  per mile and the amount of energy you  

generate each year from the Sun. And if you take  a relatively traditional car, it's like this, so  

energy consumption, energy yield. There's a big  gap. By leveraging the latest advances in solar  

technology, Lightyear maximizes energy yield. And  by focusing on efficiency in their car's design  

and engineering-- Step by step, you get the  energy consumption down. But it's still not  

at the same level as your energy yield. So  you also have to work on the other side.  

Lightyear focused on three key areas: the  powertrain, rolling resistance and aerodynamics.  

Focus Number One: The Power Train. So there's  four motors individually in each wheel,  

which means there's no longer a mechanical  drive shaft or a final drive. And all of  

these mechanical components that of course  generate friction, they add weight. You  

can get rid of all of that. This lighter,  

more efficient powertrain of course also  reduces rolling resistance--Focus Number Two.  

Lightyear One's body and chassis are also made  of lightweight materials, like aluminum and  

carbon fiber allowing the five -seat, family  car to tip the scales at an estimated fourteen  

to fifteen hundred kilograms. Many EVs currently  on the market are nearly twice as heavy. Finally,  

there's aerodynamics. Lightyear One has a drag  coefficient of less than 0.2. So it's really,  

really low compared to five seater production  cars today on the market. Keep in mind that in  

coming up with this aerodynamic design, Lightyear  also had to make room for solar panels, seats and  

take driver and passenger comfort into account.  Not the most aerodynamic shape, not the biggest  

solar panel area. So it's not the best in  one category, but the balance across all of them.  

Of course, Aptera faced the same design  and engineering challenges.  

Challenges they've been able to overcome thanks to the  latest advances in solar technology.  

One of the things thats' changed is  the efficiency of new solar cells.   

And the new solar cells that are  available, like the ones we use,  

are so efficient, they allow us to do things now  that we couldn't do 10 years ago. Like covering  

nearly every meter of their car's surface in solar  cells. But Aptera also focused on efficiency. An  

approach perhaps best exemplified by their car's  aerodynamic design. It's really the result of  

asking, what's the most aerodynamic shape that  you could put around two people side-by-side?  

And when I started thinking about building a  car and how it would look, and how we designed,  

this sort of epiphany of being stuck  on the freeway and looking at all the  

vehicles surrounding me -- trucks, and cars, and  station wagons, and everything just looked like  

big bricks to me. And so getting into, why  are cars boxy? Why are they styled that way?  

And then, why is it necessary to do  something different if you really  

want to make an efficient vehicle? Steve and his  team came up with a radically different design,  

inspired in part by the solar  racers they saw in competition.  

What we did is take that way of thinking as a  starting point and then bring it on automotive  

design and say, how do we retain the  -- technical roots and the efficiencies  

but yet make it a commercially viable vehicle.  The result: a three-wheel, two-seater car with the  

drag coefficient of zero-point-one-three, one that  the Washington Post compared to the Batmobile! The  

side view mirror--the square side view mirror  on a Ford F-150 has about the same amount of  

drag as our entire vehicle. Aptera's solar  electric vehicle also uses in-wheel motors  

as well as lightweight, composite materials  like carbon fiber and a type of fiberglass  

called E-Glass. Composites let you put more  structure, and more safe structure with less  

weight and cost than steel. The sleek design,  efficient powertrain, and use of lightweight  

materials allows for Aptera's base model to weigh  just 800 kilograms! Compared to EVs, I mean--it's  

fractional. One of the EVs we drove the  other day I think weighs over 6,000 pounds.  

To give you an example. I mean that's a tremendous amount of weight.

A lighter, more aerodynamic car means  less energy needed to move the vehicle.  

We burn about a hundred watt-hours per  mile. And -- to put that in perspective,  

it's-- much less than a motorcycle. So,  by starting with a clean sheet of paper  

and making something that's efficient from day  one. And making something that's powered by the  

Sun-- it felt like it was a way to differentiate  ourselves from anything that's out there.  

Everyone else is making electric vehicles,  we're making solar electric vehicles.  

The need for clean, sustainable transportation  has never been more urgent. And with the  

growing realization that today's EVs  may not get us to Net Zero fast enough,  

maybe it's time to explore alternative solutions  to sustainable transportation. Should it be  

something that harnesses the energy directly  from the Sun? Should it reduce our use of the  

grid? Should it give us more freedom and more  autonomy? That's the direction I'd like to see  

it go. So I do think that in the long term solar  cars will be accessible to everyone. And that's  

where our mission statement comes from: "Clean  mobility for everyone everywhere". That's what  

we want to achieve, and we see the solar car  as the opportunity to make that happen.  

For a deeper dive into solar cars, check  out Light Speed: Powered by the Sun,  

Seeker's 8 chapter learning playlist on the  technology behind the 2019 World Solar Challenge.