DEREK MULLER: Some accomplishments

in life, and sometimes the most impactful ones,

can only be achieved as a member of a team,

a synchronized group of highly focused minds,

dedicated to a common goal,

particularly when that goal

is one of the biggest problems facing humanity.

As teams rise on day two of the World Solar Challenge,

the real purpose behind this race

is never far from their minds.

Climate change is a big issue in the world.

We can see in many different places.

Many things are changing because of climate change.

And we feel with our solar car,

we are working on the technology that can help

change this.

We, of course, want to win

and that's drives a team to create new technologies,

technologies that are not yet on the market, sometimes.

And I think the beautiful thing about that is

this technology has really high potential

in more sustainable mobility.

On the first day of the race,

team Twente from the Netherlands amassed a shocking lead

and is starting day two 30 kilometers ahead of the pack.

We're in first place and we expected the other teams to be bit closer to us,

but I don't know what they are planning today.

they might have their own strategy here.

We'll keep doing our thing

and they'll keep doing their thing and yeah, let's see.

[SPEAKING FOREIGN LANGUAGE]

DRIES KETELSLEGERS: We are laying fourth here

together with three others teams.

There's just one team ahead which is Twente.

They're half an hour ahead, I think,

but that doesn't really matter at the moment

'cause the race is 3,000 kilometers

so maybe they burned up too much fuel yesterday

and they're gonna run out of energy at the end. So we don't know yet.

MULLER: Catching Twente may come down to each team's individual race strategy,

which they spent two years meticulously designing and simulating.

SIDD BIKKANNAVAR: So if you're a strategist,

you are spending most of that morning in the back seat of a chase vehicle

behind a whole row of computers,

running last minute calculations,

taking into account the day's weather forecast

which is now much more accurate.

KETELSLEGERS: At 8:00, we do a simulation

and now we know what time we're gonna arrive today

and where we're gonna be and at what percentage in battery.

Everything is a test of the car but it's also test of the team.

It's a very strategic, calculated and methodical thing.

ALL: [CHANTING] Blue fight, blue fight, blue fight.

-So exciting today. -Good luck to you.

Thank you.

MULLER: Day two is officially under way.

The heat is blistering and all the teams have their eye on Twente.

Running second is Vattenfall followed by Top Dutch.

The three trailblazers are all Dutch teams.

Behind them is Agoria, Sonnenwagen, and then Michigan.

But not everyone is off to such a good start.

MULLER: Western Sydney has been having trouble

since the beginning of the race.

were just not sure at the moment.

The mech team's having a look.

There was something sounding funny, so we had to stop.

MECHANIC: No... Oh [BLEEP]

MAX MAMMONE: Day two, the race didn't go as planned.

After charging, we ended up

realizing there was a big software glitch in the car.

MULLER: What seems like a simple software issue could take all day to fix.

With hours of delay ahead, it's safe to say Western Sydney

is out of the running to win this race.

MAMMONE: We had a lot of ups and downs but we all know as a team

and myself know that that car is one of the top ones out on the grid.

Just unfortunately this time it didn't kind of work out

but there's multiple other races coming up

and maybe we can make it work there.

[CHEERING]

[MAN SPEAKING FOREIGN LANGUAGE]

MULLER: Out on the road, the teams continue to make strategic decisions

based on constantly evolving conditions.

When we're out in the outback, we're always watching the weather,

'cause sun is the most important thing,

that's what we wanna be at all times.

So we have a car

that gets in a satellite feed with the weather.

And, for example, we can see... Oh, there's a cloud coming in.

Well, what will we do now? Will we slow down to not waste too much energy

or will we speed up to get out of the cloud as fast as possible?

That's strategic decisions we have to make every time.

MULLER: At the heart of every team's strategy is energy management,

a constant juggling act between the car solar panels,

the battery

and the motor that propels it down the road.

In a perfect world,

the cars use the sun's energy alone to maintain their speed.

This is called running energy-neutral.

VAN HAM: There is always a certain speed

during the race where we take in

exactly as much energy as we're using

so the solar panels brings in everything.

But if you wanna drive faster than that,

let's say to over take another team,

we have to used energy from our battery storage

which then drain the battery.

MULLER: Teams will tap into the battery for a variety of reasons,

including a dip in the sun's energy from cloud cover,

fighting headwinds, or simply making up time in the race.

But it always comes at a cost.

VAN HAM: Our number one concern strategically is that

we can run out of battery power.

Then we have to stop right then and there and charge the car.

ANDREW DICKINSON: So, you're always trying to balance,

you're always trying to use the energy in the best way

that you possibly can to get you

to the finish line as fast as you can.

MULLER: One of the biggest drains on the car's batteries

comes from overtaking other teams,

making passing one of the most critical

strategic maneuvers of the race.

[SPEAKING FOREIGN LANGUAGE]

MULLER: And it isn't long before Agoria

is knocking on Top Dutch's door.

DICKINSON: If you have to increase your speed,

in order to overtake someone,

you're losing energy, you're going faster than you want to be.

And so teams will generally pass each other at a crawl

and sometimes that can get kind of dangerous.

So it's very important

procedurally that everyone is watching for oncoming traffic

that your lead vehicle is in the right place and right time

in order to make sure that happens safely and smoothly as possible.

We are driving behind Top Dutch right now

and they are driving at 95 kilometers per hour.

We will drive 100 kilometers per hour so we'll overtake them.

That's really nice.

[SPEAKING FOREIGN LANGUAGE]

MAN: He's passing.

-[CLAPPING] -[MAN SPEAKING FOREIGN LANGUAGE]

We are here at Tennant Creek.

This is the first stop of the second day.

We are now nearly

1,000 kilometers away from Darwin.

That is one third of the distances to Adelaide.

Control stops are mandatory checkpoints along the route.

All teams must punch in and out for a 30-minute break.

And for safety, change drivers.

So far, the story has been the team Twente.

They've pulled out to an enormous lead.

On day one, they were ahead by half an hour

and now is trying to maintain that lead.

There is the arrival of the team Twente vehicle,

the first car to arrive here in Tennant Creek.

So, I'm wondering if there's something about the stability

of the car or just their solar panel,

something about the way they're designed

that is leading to this advantage.

Vattenfall has arrived.

I have to say, I wasn't expecting to see them this quickly.

How did you feel about the way the car was driving?

Occasionally we drive doing a 100-plus kilometers an hour

and we're energy-neutral, and that's an amazing feelings to experience.

That's extraordinary.

Agoria, the team from Belgium, is in next.

It's very important for our team to prepare

for our control stops as good as possible.

[SPEAKING FOREIGN LANGUAGE]

Because in 2017, the difference between

the fourth and the third position was only seven minutes.

There are 250 kilometers until the next control stop.

What you can see up here

is that team Twente is getting their ballast ready.

They're getting ready to jump back in the car,

whereas Agoria has basically just arrived.

So, there's maybe 25 minutes separating these teams.

That gap is narrower than it was yesterday.

So, really looks like the things are tightening up at the front of the race.

Ooh!

MULLER: One unique component of Tokai's

strategy is that they have an interchangeable motor,

one for high speeds and one for low speeds

when they need more acceleration.

This gives them the ability to adapt their gearing from day to day.

MULLER: Perhaps the most spirited battle

is going on in the fourth and fifth positions.

As they predicted, team Tokai from Japan has closed the gap

on Michigan from the us.

It can take hours to plan and achieve a pass in this race,

and Tokai has had their eye on Michigan all day.

With the traffic finally clear, the Japanese team makes their move

Tokai accelerates through

what seems to be an effortless pass,

and continues far out of Michigan's line of sight.

Holding on to considerable speed a quarter mile up the road,

Tokai has approached the Michigan lead convoy car, looking to pass.

[MAN SPEAKING OVER MIC]

Thank you.

[MAN SPEAKING OVER MIC]

MULLER: Now, all convoy vehicles are required to give way

to any solar car looking to pass.

MULLER: But the Michigan vehicle is picking up its speed.

[TEAM MEMBERS TALKING OVER MIC]

MULLER: And now, approaching a stretch of no passing zone,

Michigan slows way down, impeding Tokai while they cannot safely

or legally pass.

[TEAM MEMBERS TALKING OVER MIC]

MULLER: Once clear of the no passing zone, Tokai tries again.

But the Michigan car speeds up once more,

not allowing the solar car to get around.

[TEAM MEMBERS TALKING OVER MIC]

MULLER: Tokai finally has to surrender to oncoming traffic

and tuck back into their lane.

MULLER: And the game repeats,

allowing the Michigan solar car

to recoup all the distance that Tokai had pulled ahead.

[TEAM MEMBERS TALKING OVER MIC]

MULLER: I'm not too sure if this fits into either the rules

or the ethics of this race.

That will be up to Tokai and the race officials.

MULLER: Oh, it is hot, here in Barrow Creek

at the second checkpoint for day two.

And what's remarkable to me is just how much Twente

has been able to maintain it's advantage over these other cars.

You know, on day one, they could have been bluffing,

they could have been draining their battery to go extra fast

but towards the end of day two,

it's hard to believe that they can still be bluffing on battery.

I gotta believe that Vattenfall and Agoria are trying as hard as they can

to pull back that lead.

Well, Vattenfall is second to arrive here

and by the looks of things, it's just on time.

Basically they are holding Twente's lead.

So important for these teams to get that solar panel position

exactly correct so that they're getting the best angle

on the sun and maximizing the juice that they can recover