Yet here we are a decade later, "Oil everywhere! We’ll never run out of oil!" So, which is it?

Right now, the world produces a whopping 93 million barrels of oil every day, but more than a trillion barrels still sit in Earth’s crust.

We’ve already gotten most of Earth’s "easy" oil, but new technologies like horizontal drilling and hydraulic fracturing are giving us to access more and more of it.

But considering the impact of fossil fuels on the climate and environment, we have to ask, "When will we be done with oil?"

If the history of energy is any guide, how much oil we pump up to the surface and ultimately into the atmosphere, depends a lot on what other energy options we have.

In the 17th century, there were 820 million acres of virgin forest in the United States,

but after a few centuries of burning wood for heat, energy, and cooking, that number had dwindled to just 138 million.

At some point in the mid-1800s we reached "peak wood."

Luckily, we had an alternative fuel that, at least at the time, promised to be environmentally friendly and save the forests: coal.

Likewise in 1846, thanks to the popularity of whale oil as a smokeless lamp fuel, we reached "peak whale."

Whales are a decidedly non-renewable resource. Our love of lamp almost drove them extinct.

I love lamp. I love lamp.

But it wasn’t simply dwindling supply and increasing demand that saved the cetaceans.

It was the discovery of a new lamp fuel called kerosene, distilled from a black liquid that we’d recently learned how to pump out of the ground.

Now, if oil saving the whales seems like an odd idea, that’s because the history of energy in America tends to be solving one problem by introducing another.

We used to think that tool use was our defining human characteristic, until we saw chimps do it.

Then we claimed language as our own, until we met a gorilla named Koko.

But the ability to intentionally manipulate energy to do stuff seems to be a distinctly "us" thing. Although, there’s those beavers.

Anyway, how a society uses energy is one of its defining characteristics.

Humans first harnessed thermal energy, and then kinetic energy, but there's no easy way to convert one to the other, until the steam engine.

This ability to convert and control energy led to the Industrial Revolution, which was a pretty big deal.

As a rule in history, as a society gets more advanced, it consumes more energy, and we’re no different.

The story of the 20th century is one of more energy, for more people, used for more things.

But that’s not the only trend.

The past centuries have seen a general trend from wood to coal to oil to renewables, and today we get our energy from more sources than ever before.

Renewable energy in particular has grown in the past ten years.

We’re also getting more energy per unit of CO2 than ever before.

We hear a lot about reducing carbon today, but we’ve been on that path for a long time.

But even though more efficiency and less consumption means that we’re using fewer fossil fuels over the past decade,

total consumption has gone up faster, so emissions are still higher than they were 4 decades ago, and fossil fuels are still number 1 by a big margin.

U.S. energy use matches the rest of the world pretty closely.

I’m not sure if that’s a good or a bad thing, but it means that my problems are your problems are everyone’s problems.

Unfortunately, the Energy Information Administration projects that where we all get our energy won’t change much over the next two decades,

and well, have you heard about this whole climate change thing?

The history of energy transitions has been one of new energy sources taking the place of dirtier, scarcer ones.

But considering that with the exception of nuclear, all of our energy technologies date from the 19th century, inventing new energy sources is a thing of the past.

But as CO2 levels continue to climb past 400 parts per million, waiting for peak oil might not be an option.

For the first time in our history, we might have to invent a peak of our own.

Be sure to check out the other videos in the series about energy by clicking above or you can check down in the description.

The world of energy is really complex and confusing, but we should know how it works.

Luckily, the Webber Energy Research Group with the University of Texas has put together an amazing online course called "Energy 101."

They got versions for desktops, mobile devices, everything.

If you wanna know more about that massive machine that exists behind your electrical outlet and inside the gas pump, it's really really awesome. You'll understand like all of energy.

They also regularly publish a poll of what people think about energy is. Objective, scientific. And if you like polls, its a good one.

There's links to all that stuff down in description, along with lots more. Stay curious.