NOVA

Gemstones, precious metals,

and power...

building blocks of civilization.

But how are they created?

Our Earth is a master chef.

She knows how to cook.

These gems are really forged

in unimaginable conditions deep inside the planet.

How did metal shape our past?

I love steel.

It's actually the backbone of our society.

And how will these gifts be used to build the tools of tomorrow?

Such a simple element has enabled all of the technology

that surrounds us today.

It is amazing that this came

from the sand in our deserts.

We're going to launch this incredible telescope,

and we're going to send it a million miles into space

from the Earth

to actually unlock the secrets of the universe.

And it will all rely on two ounces of gold.

In this episode,

we go deep into the fuels that drive our world.

It's amazing that we can see it with our own eyes.

What are their secrets?

Look! This is what we've been looking for.

You're holding in your hand huge amounts of energy.

And what are their risks?

We're affecting our planet.

Humans affect the planet.

Can we discover new treasures

to satisfy our energy needs?

In this rock,

there is an incredibly powerful untapped force.

If we just get it right, there's huge potential.

"Treasures of the Earth," right now on NOVA.

Major funding for NOVA is provided by the following...

All around us,

Earth's spectacular riches are on display:

mountains, oceans,

and plentiful crops.

But Earth's bounty is not just skin deep.

Some of our most important resources

are forged even deeper inside our planet.

These treasures are the fuels we depend on.

They may not be beautiful, but they power our modern world.

We use them to heat, to cool,

to light up our cities.

They drive our cars

and propel our planes.

They have allowed us to build our civilization.

But what secrets are locked inside

that give them so much power?

And today, as we learn that some of these treasures

are affecting our climate

and pose a threat to our survival,

can we find new treasures

and new ways to keep the power on?

The way to start finding answers

is to trace the energy back from the plug on your wall.

New York City, America's largest,

and center of its corporate and cultural power.

Keeping the bright lights of this big city on

is this man's job.

Any outages right now?

Craig Ivey, No

president of the power utility known as Con Ed.

Without electricity,

the subway doesn't run and the elevators don't run.

New York is the financial center of the world,

the media capital of the world.

We have to maintain reliability in the city.

This is the nerve center.

I want to get that expedited.

So everything going on

within the grid is monitored 24/7/365.

Here in Con Ed's master control room,

experts keep a close eye on the network of cables,

transformers, and power stations

that deliver the city's electricity,

called the grid.

As New York heads into summer,

when air conditioners run full blast,

this nerve center gets even busier.

This can be an exciting place.

Well, they found a defect in the transformer.

This is a serious-minded group all the time,

but on those peak summer days, the intensity ratchets up.

How are they doing on the 53M?

That's when the stress level inside this room goes up.

You can't change summer.

People want to be cool,

they want to be comfortable, so therefore,

when customers want it, we have to produce it.

The high demand for electrical power

starts here, where you plug in your coffee maker and computer,

lights, washing machine, TV,

and one of the hungriest of all, your air conditioner.

That means Con Ed must provide a million watts

of electricity continuously during peak hours

every few blocks.

All that adds up to as much electricity

as some entire countries.

There are enough underground electrical cables

in New York City

to wrap around the Earth almost four times.

At the end of those power lines

is the source of all that electricity.

A power plant.

At its center is a massive, 15-story-high ball of fire.

Most people take power for granted,

and until it's not there for them

do they realize how important it is.

Tommy Quartuccio is the director

of the largest power plant in New York.

2,300 megawatts is what we can put out,

about 22% of the power for New York City.

So we're very important.

Ravenswood Generating Station,

nicknamed Big Allis, was once the world's largest.

During the summer period, the units run continuously.

The control room operators are around the clock.

We're here 24 hours a day,

seven days a week, 365 days a year.

Despite the enormity of the task,

supplying the electricity New York needs

comes down to a relatively simple machine

first invented in the 1880s: a turbine.

At its most basic,

a turbine is something like a fan with blades

turned by steam power.

Its shaft spins a generator with magnets

that create a flow of electrons.

That flow of electrons is electricity.

What generates that steam?

Well, that depends.

A steam turbine.

It swallows steam no matter what it's made from,

any type of fuel: coal, natural gas, or oil.

The turbine doesn't care.

It all comes down to what is available, cheapest,

and most reliable.

Today, Big Allis burns 99% natural gas

in massive boilers.

This is where it all happens, right inside the boiler.

The boiler, 15 stories tall

and 2,000 degrees, is a swirling ball of fire.

This fire can consume

nine million cubic feet of natural gas every hour,

a volume equivalent to more than 100 Olympic swimming pools.

But natural gas wasn't always what made Big Allis run.

When it first came online, it burned coal.

Coal has been phased out in New York,

and its use is on the decline across the U.S.

as its environmental and health dangers become more apparent.

But when New York City was built, coal was king.

It is the fuel that built much of our country,

partly because North America

has the largest coal reserves in the world.

In the near total darkness of a coal mine,

you begin to understand why coal played such an important role.

Oh, here it is!

This dark black chunk of the wall here?

This is where the miners would have come,

and they would have worked in these dark and wet

and cold tunnels to pull out this coal.

Liz Hajek,

a geologist from Penn State University,

says today, coal produces only a third of U.S. electricity.

But in its heyday, it was our primary source of power,

and this Pennsylvania coal was prized above all.

There's a bunch of different types of coal...

there's brownish, lignite, bituminous...

but this is anthracite coal.

It's dark, it's shiny, it's almost all carbon,

and it means it would have been really valuable

to the miners that were coming down into the mine.

The mountains of Ashland, Pennsylvania,

hold the world's largest known deposits of anthracite coal.

But why?

According to Hajek, the rocks above the mine give us a clue.

So, this is shale.

What we know, we can look at this rock

and we can figure out what this landscape

used to look like over 300 million years ago.

These rocks formed long ago, even before dinosaurs.

And in this case,

we know that this shale formed in a swampy environment.

Look! This is what we've been looking for.

Here, if you look closely, you can see this is a leaf.

This leaf would have grown

in these coal swamps, so these swamps would have looked like

the Gulf Coast of the United States today,

or maybe the Florida Everglades.

Over millions of years,

those trees pulled carbon out of the air

through photosynthesis...

the way plants use sunlight and water to grow.

When the trees died,

that carbon got buried underground