Hi, it's Mr. Anderson, and this is AP Environmental Sciences video 24. It's on fossil fuels.
We really do live in the age of fossil fuels. Most of the energy that I am using and you're
using right now is probably coming from coal, oil and natural gas. And I have grown
up around gasoline stations like this Sinclair station. I remember thinking as a kid that
fossil fuel meant that the fuel had to come from the bones of ancient dinosaurs. It could
come from that if that if that dinosaur was stranded in an ancient ocean and was fragmented
and deposited on the bottom of the ocean with billions of microscopic plants and animals.
And then quickly covered by sediment, and then heat and pressure were to squeeze it anaerobically
to make oil and gas. But that's probably what didn't happen to most dinosaurs. Regardless,
fossil means coming from once living material. And it is formed anaerobically in an area
underneath the earth where there isn't oxygen available for decomposition. It comes in three
different types, solids, liquids, and gases. We've got coal, petroleum, and natural gas. Coal
is formed when we have a swampy area that overtime this forested area is covered with sediment.
We squeeze it. We remove a lot of the moisture and then over time heat and pressure forms
peat. And then lignite and then forms of different types of solid coal. And we can simply combust
this and we get a lot of energy out of it. If we are looking at petroleum, crude oil
is probably what you are most familiar with, we pump that liquid out of the ground. And
we can also take solids like oil sands and oil shale. We can mine that and process it
to make this liquid. And then finally we have natural gas, which is going to be methane.
Now all forms of fossil fuels are going to have advantages and disadvantages. The big
advantage of all of them is that they have a huge amount of energy. The big disadvantage
is the environmental impacts they are having on our planet. There are impurities found
that are released into the atmosphere. So we have air pollution. Sulfur dioxide is an
example of that. And then more importantly we are putting carbon dioxide into the atmosphere
which is leading to global warming. And then finally they're nonrenewable. They are unevenly
spaced on our planet and they are finite. We are going to run out of fossil fuels over
time. But right now it is the fuel of choice. Oil, coal and natural gas is where the world
is getting its energy. A little bit is coming from nuclear. A little bit is coming from
renewables and a lot of that is actually coming from wood. But if we are to look at how they
are formed, coal is formed where we have a swampy area. It is covered over time. And
as we squeeze it over time it forms something called peat. We can actually combust that
but we do not get as much energy. Over time more heat and pressure can squeeze the moisture
out. We are left with more of the carbon. It forms something called lignite. And then
it can form something called coal overtime. But we can have different grades of coal.
More impurities or less impurities. One of the most pure is called anthracite. And it
is just essentially all carbon and burns fairly clean. So how do we use coal? You simply dig
it up on the surface, on these huge strip mines and sometimes underneath the surface.
Then we move it where it needs to be. And then we combust it. It generates a huge amount
of steam and then we can generate electricity. This is a huge power plant down in Utah. What
are some advantages of it? It is super cheap. It is easy to dig it up. We get a huge return
on our investment. It is plentiful. It is going to be found in lots of countries on
our planet. And it is easily mined. What are some disadvantages? It is really dirty. It
has a huge amount of impurities in it. Some coal will have up to four percent sulfur and
that releases sulfur dioxide into the atmosphere. We also have a lot of the ash that is left
behind when we combust it. So we have to store that. And then finally it is increasing carbon
dioxide in the atmosphere. If we look at the petroleum, how is that formed? It is formed
in these ancient oceans where we have microscopic life being deposited on the ocean floor. It
is covered with sediment. And then over time that sediment puts more heat and pressure.
It is now covered so it is in an anaerobic environment. And we eventually form oil. And
a lot of the time we will have natural gas bubbling up to the top. And so how do we get
it out? We simply dig down and we pump that oil out of the ground. That crude oil is then
refined. So we will ship it to a refinery. We can heat it and we can get things like
diesel, petroleum, gasoline, fuel oil, depending on how we process it. Now another form of
petroleum are the oil shales and the oil sands. So they are a solid. But we can mine that.
We can process it. And we can make a liquid fuel. And that is one of the big advantages
of petroleum. It is a liquid and so we can move it where it needs to be. And it is also
super important in transportation. It works really well in your car. It is energy dense,
more energy dense then we are going to find in coal. And it is actually a little bit cleaner
than coal. Less impurities. Less carbon dioxide per amount of energy that we are producing.
What are the problems? It still has some impurities in it. And also since it is moveable we are
more likely to have accidents. So oil spills for example as we move that oil around. And
then finally it is a greenhouse gas. It is putting carbon dioxide into the atmosphere.
If we look at natural gas it is simply methane gas. We burn it and we can get energy out
of it. One of the big advantages of natural gas is we can use it in heating. It is cleaner
than oil and coal. Some people call in the clean fossil fuel. It has lower carbon dioxide
per amount of energy that is being used. What are some of the disadvantages? It is methane
which is a huge green house gas. So if some of that is released it gets into the atmosphere
and causes global warming. The exploration of finding natural gas is going to destroy
sediment a lot of the time. And then actually taking it out, a big process they are now
using is hydraulic fracturing, where we are squeezing fluids into the crust and that can
lead to earthquakes and also contamination of the water table. If we look at big environmental
impacts, the big one is the amount of carbon dioxide in the atmosphere. So if we look at
the amount of carbon being pumped into the atmosphere world wide, you can see it is increasing
over time, exponentially. Where are the big culprits? It is going to be coal, oil, natural
gas and actually the processing of cement or making of cement is a huge greenhouse gas
emitter as well. Aside from environmental impacts, they are nonrenewable. This is the
Hubbert curve. And what we are looking at is as we discover something like oil in Texas
or in the US or in Norway for example, we will extract a lot of it but eventually it
is going to drop off over time. And so we have what is called peak oil. In other words
we are not going to harvest anymore oil. If we look at how that idea of the Hubbert curve
works with the amount of oil that we are getting, we will see that it does not necessarily match
up. This is that Hubbert curve of peak oil. But this is the actual oil, crude production.
And the reason why it is not peaking off is because we are discovering new ways of finding
oil. If we look at where the fossil fuels are formed, again thinking about how coal
is made, it is going to be in areas that are massive and have lots of forested regions.
And so the biggest oil reserves are going to be found in the US, Russia and China. China
is actually using coal more than any other country at this point. If we look at oil reserves,
most of these are going to be in the middle east so Venezuela, Saudi Arabia, Canada. But
then we go to Iran, Iraq, Kuwait. That is where most of our oil is going to be found.
And then if we look at the gas reserves, we are going to have gas in Russia, Iran, Qatar.
But a lot of this again is going to be found where the oil is. It is going to be found
in those Middle Eastern countries. And so did you learn the following? Could you pause
the video at this point and fill in the blanks? I will do it for you. Fossil fuels are formed
in an anaerobic environment. Coal is formed where we have vegetation squeezed to make
peat, then lignite, then coal. Petroleum can come in the form of crude oil or oil sands
and oil shales. We are looking at natural gas, that is methane. There are advantages and
disadvantages of each. The big ones are environmental impacts, especially carbon dioxide. And then
the idea that they are nonrenewable. We have reserves that are found on our planet, but
they are finite and we are going to run out of those and we are going to have to move
towards renewable resources. So I hope you learned all of that and I hope that was helpful.