Fossil Fuels


In this video Paul Andersen explains how fossil fuels are formed when organic material is heating and squeezed in an anaerobic environment. Formation, extraction, advantages, and disadvantages are discussed for coal, petroleum and natural gas.


Transcript Provided by YouTube:

00:04
Hi. It’s Mr. Andersen and this is AP environmental sciences video 24. It is on fossil fuels.
00:09
We really do live in the age of fossil fuels. Most of the energy that I am using and you
00:14
are using right now is probably coming from coal, oil and natural gas. And I have grown
00:19
up around gasoline stations like this Sinclair station. I remember thinking as a kid that
00:23
fossil fuel meant that the fuel had to come from the bones of ancient dinosaurs. It could
00:28
come from that if that if that dinosaur was stranded in an ancient ocean and was fragmented
00:33
and deposited on the bottom of the ocean with billions of microscopic plants and animals.
00:37
And then quickly covered by sediment and then heat and pressure were to squeeze it anaerobically
00:43
to make oil and gas. But that is probably what did not happen to most dinosaurs. Regardless,
00:48
fossil means coming from once living material. And it is formed anaerobically in an area
00:53
underneath the earth where there is not oxygen available for decomposition. It comes in three
00:58
different types, solids, liquids and gases. We have coal, petroleum and natural gas. Coal
01:03
is formed when we have a swampy area that over time is forested areas covered with sediment.
01:08
We squeeze it. We remove a lot of the moisture and then over time heat and pressure forms
01:14
peat. And then lignite and then forms of different types of solid coal. And we can simply combust
01:20
this and we get a lot of energy out of it. If we are looking at petroleum, crude oil
01:24
is probably what you are most familiar with, we pump that liquid out of the ground. And
01:28
we can also take solids like oil sands and oil shale. We can mine that and process it
01:32
to make this liquid. And then finally we have natural gas, which is going to be methane.
01:37
Now all forms of fossil fuels are going to have advantages and disadvantages. The big
01:42
advantage of all of them is that they have a huge amount of energy. The big disadvantage
01:45
is the environmental impacts they are having on our planet. There are impurities found
01:49
that are released into the atmosphere. So we have air pollution. Sulfur dioxide is an
01:53
example of that. And then more importantly we are putting carbon dioxide into the atmosphere
01:57
which is leading to global warming. And then finally they are nonrenewable. They are unevenly
02:01
spaced on our planet and they are finite. We are going to run out of fossil fuels over
02:05
time. But right now it is the fuel of choice. Oil, coal and natural gas is where the world
02:11
is getting its energy. A little bit is coming from nuclear. A little bit is coming from
02:16
renewables and a lot of that is actually coming from wood. But if we are to look at how they
02:20
are formed, coal is formed where we have a swampy area. It is covered over time. And
02:25
as we squeeze it over time it forms something called peat. We can actually combust that
02:30
but we do not get as much energy. Over time more heat and pressure can squeeze the moisture
02:35
out. We are left with more of the carbon. It forms something called lignite. And then
02:38
it can form something called coal overtime. But we can have different grades of coal.
02:43
More impurities or less impurities. One of the most pure is called anthracite. And it
02:46
is just essentially all carbon and burns fairly clean. So how do we use coal? You simply dig
02:52
it up on the surface, on these huge strip mines and sometimes underneath the surface.
02:56
Then we move it where it needs to be. And then we combust it. It generates a huge amount
03:00
of steam and then we can generate electricity. This is a huge power plant down in Utah. What
03:05
are some advantages of it? It is super cheap. It is easy to dig it up. We get a huge return
03:09
on our investment. It is plentiful. It is going to be found in lots of countries on
03:13
our planet. And it is easily mined. What are some disadvantages? It is really dirty. It
03:17
has a huge amount of impurities in it. Some coal will have up to four percent sulfur and
03:21
that releases sulfur dioxide into the atmosphere. We also have a lot of the ash that is left
03:26
behind when we combust it. So we have to store that. And then finally it is increasing carbon
03:30
dioxide in the atmosphere. If we look at the petroleum, how is that formed? It is formed
03:34
in these ancient oceans where we have microscopic life being deposited on the ocean floor. It
03:39
is covered with sediment. And then over time that sediment puts more heat and pressure.
03:44
It is now covered so it is in an anaerobic environment. And we eventually form oil. And
03:49
a lot of the time we will have natural gas bubbling up to the top. And so how do we get
03:53
it out? We simply dig down and we pump that oil out of the ground. That crude oil is then
03:59
refined. So we will ship it to a refinery. We can heat it and we can get things like
04:03
diesel, petroleum, gasoline, fuel oil, depending on how we process it. Now another form of
04:09
petroleum are the oil shales and the oil sands. So they are a solid. But we can mine that.
04:14
We can process it. And we can make a liquid fuel. And that is one of the big advantages
04:18
of petroleum. It is a liquid and so we can move it where it needs to be. And it is also
04:22
super important in transportation. It works really well in your car. It is energy dense,
04:27
more energy dense then we are going to find in coal. And it is actually a little bit cleaner
04:30
than coal. Less impurities. Less carbon dioxide per amount of energy that we are producing.
04:35
What are the problems? It still has some impurities in it. And also since it is moveable we are
04:41
more likely to have accidents. So oil spills for example as we move that oil around. And
04:46
then finally it is a greenhouse gas. It is putting carbon dioxide into the atmosphere.
04:50
If we look at natural gas it is simply methane gas. We burn it and we can get energy out
04:55
of it. One of the big advantages of natural gas is we can use it in heating. It is cleaner
05:00
than oil and coal. Some people call in the clean fossil fuel. It has lower carbon dioxide
05:05
per amount of energy that is being used. What are some of the disadvantages? It is methane
05:09
which is a huge green house gas. So if some of that is released it gets into the atmosphere
05:13
and causes global warming. The exploration of finding natural gas is going to destroy
05:18
sediment a lot of the time. And then actually taking it out, a big process they are now
05:23
using is hydraulic fracturing, where we are squeezing fluids into the crust and that can
05:29
lead to earthquakes and also contamination of the water table. If we look at big environmental
05:33
impacts, the big one is the amount of carbon dioxide in the atmosphere. So if we look at
05:37
the amount of carbon being pumped into the atmosphere world wide, you can see it is increasing
05:41
over time, exponentially. Where are the big culprits? It is going to be coal, oil, natural
05:46
gas and actually the processing of cement or making of cement is a huge greenhouse gas
05:51
emitter as well. Aside from environmental impacts, they are nonrenewable. This is the
05:56
Hubbert curve. And what we are looking at is as we discover something like oil in Texas
06:00
or in the US or in Norway for example, we will extract a lot of it but eventually it
06:05
is going to drop off over time. And so we have what is called peak oil. In other words
06:09
we are not going to harvest anymore oil. If we look at how that idea of the Hubbert curve
06:13
works with the amount of oil that we are getting, we will see that it does not necessarily match
06:18
up. This is that Hubbert curve of peak oil. But this is the actual oil, crude production.
06:23
And the reason why it is not peaking off is because we are discovering new ways of finding
06:27
oil. If we look at where the fossil fuels are formed, again thinking about how coal
06:32
is made, it is going to be in areas that are massive and have lots of forested regions.
06:38
And so the biggest oil reserves are going to be found in the US, Russia and China. China
06:43
is actually using coal more than any other country at this point. If we look at oil reserves,
06:48
most of these are going to be in the middle east so Venezuela, Saudi Arabia, Canada. But
06:51
then we go to Iran, Iraq, Kuwait. That is where most of our oil is going to be found.
06:56
And then if we look at the gas reserves, we are going to have gas in Russia, Iran, Qatar.
07:01
But a lot of this again is going to be found where the oil is. It is going to be found
07:04
in those Middle Eastern countries. And so did you learn the following? Could you pause
07:08
the video at this point and fill in the blanks? I will do it for you. Fossil fuels are formed
07:12
in an anaerobic environment. Coal is formed where we have vegetation squeezed to make
07:17
peat, then lignite, then coal. Petroleum can come in the form of crude oil or oil sand
07:22
or oil shales. We are looking at natural gas, that is methane. There are advantages and
07:27
disadvantages of each. The big ones are environmental impacts, especially carbon dioxide. And then
07:32
the idea that they are nonrenewable. We have reserves that are found on our planet, but
07:35
they are finite and we are going to run out of those and we are going to have to move
07:38
towards renewable resources. So I hope you learned all of that and I hope that was helpful.


This post was previously published on YouTube.

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