Energy Consumption


In this video Paul Andersen explains how humans have consumed energy through history and may consume energy in the future. Sources of energy have included food, animals, wood, wind, coal, oil, and natural gas. However non-renewable energy source eventually lead to an energy crisis as supplies go down or prices go up. Humans will hopefully use more renewable energy sources in the future.

Transcript Provided by YouTube:

00:05
Hi. It’s Mr. Andersen and this AP environmental sciences video 23. It is on energy consumption.
00:09
I think about the amount of energy that my body requires in one day, it is really not
00:13
that much. A little over 2000 kilocalories of energy. And I could get most of that in
00:18
one large pepperoni pizza. But I use more energy than that. Right now I am using a computer.
00:22
I am using the internet. I am using lights. I am heating my house. If I go somewhere I
00:27
am probably going to drive. And if we were to put that in pizzas the average person in
00:31
the US requires over 300 large pepperoni pizzas of energy everyday. And most of that energy
00:38
is coming from fossil fuels. As we talked about in the last video energy is the ability
00:43
to do work or transfer heat. And if we look at human consumption of energy over time,
00:49
we can learn lessons from the past as we plan towards the future. And where did our energy
00:53
come from to begin with? Just like that pizza it came from our food. But it did not take
00:58
long before humans discovered fire and we could unlock the power found within wood.
01:03
We domesticated animals, and we could leverage some of their power. We used wind power very
01:08
early, grinding up grains and moving water around. And our society started to grow. But
01:12
as the population increased we underwent our first energy crisis. An energy crisis occurs
01:18
when you have a lack of supply or an increase in the price of the source of that energy.
01:24
In this case deforestation was leading to a decrease in the amount of wood and charcoal
01:29
that we had. We could not support our population. Thankfully we discovered coal. Coal has a
01:34
much larger return on investment, way more energy. It is wood, but wood that was deposited
01:39
way underneath the earth thousands of years ago. And we could get energy from that. It
01:44
led us into the industrial revolution. We then discovered oil and gas. But with each
01:49
of these, since they are nonrenewable energy sources, we have seen and will continue to
01:55
see a number of energy crisis as well. And so as we plan towards the future it is important
02:00
that we come up with an economic solution for our energy. And so we should look at the
02:04
energy’s return on investment. As we start to see a decrease in oil things like wind
02:11
and solar are going to be more feasible or more viable over time. And we also have to
02:15
consider the externalities. These are fossil fuels that we are using and with that we are
02:20
increasing pollution. We are increasing global warming. And so as we plan for the future
02:25
we want to shift towards renewable sources of energy. And more importantly sustainable
02:30
so that over time we have a consistent amount of energy and we eliminate the energy crisis
02:35
over time. And so if we look at our energy sources over time, this is from 1776 until
02:40
today, you can see a huge increase in the amount of wood that we were using. But over
02:44
time that was replaced by coal. You see an exponential growth in coal. We then see an
02:49
exponential growth in oil, in gas. We see an increase in nuclear. Right now we are seeing
02:55
an increase in renewable resources as well. And so over time we will get a decrease in
03:01
the supplies of these energy sources. And an energy crisis occurs if we have a decrease
03:05
in supply and also an increase in price. And so if we look at price for a second, this
03:10
is the price of oil in the US since it was essentially discovered. You can see it is
03:15
variable to begin with. The lower line here is the price and the upper line is putting
03:19
it in the modern day 2008 dollars. You can see that oil prices were fairly consistent
03:24
for a long period of time. You can see a big jump right here. Why is that? We had the 1973
03:30
oil crisis or energy crisis. What caused that? It was foreign policy. The US was involved
03:36
in the Yom Kippur War. We were funding Israel. OPEC, a number of Arab countries put an embargo
03:43
on the oil, so we could not get cheap oil from the Middle East. And as a result the
03:47
price went from $3.00 a barrel up to $12.00 a barrel. And as a result we had lines at
03:52
the pump. There was not enough gas. We saw another oil crisis in the 1970s as well with
03:57
the Iranian Revolution. There was this decrease in supply at this point, increase in price.
04:03
Again we had huge lines at the pump. And there were government policies put forward to start
04:08
to increase mileage of cars for example and ways that we could conserve our oil. We saw
04:14
the same thing in 2003. This is a multifactorial cause. A lot of it has to do with global requirements
04:21
for energy. We see a huge increase in oil prices as well. Now the oil prices are dropping
04:26
off. But over time, since it is a nonrenewable resource, we are going to have decreases in
04:31
the amount of oil that we can find, increases in the price over time. And if we look at
04:36
where is our energy coming from today, it is oil, coal and natural gas. That is where
04:41
most of our energy is coming from right now in the world. Now the renewable sources are
04:47
a growing segment. But if we look at that there is still traditional biomass. So this
04:52
is going to be wood that makes up 9 percent of the energy that we are getting from our
04:56
environment. And so overtime what we have to move towards is away from nonrenewable
05:01
and towards renewable sources of energy. Now we will not just due that on our own. As the
05:06
model we have talked about before, the earth supports society and everything is driven
05:11
by the economy. We have to have economic drivers that are going to move us towards these renewable
05:16
sources of energy. And a good way to look at that is the energy return on investment.
05:20
Basically what you do is you look at a ratio of how much energy it requires to get the
05:24
energy source, and how much we get out of it. So it is a ratio of energy acquired versus
05:29
energy consumed to get that energy. And so if we look at something like hydropower, for
05:33
everyone $1 invested we get $100 of energy back. Or coal is going to be an 80 to 1 ratio.
05:40
Now things that you may have heard put forward as a solution, if we look at ethanol coming
05:44
from corn, it is going to be around 1.3 to 1. And so we have to put a huge amount of
05:49
energy to grow the corn. We use fossil fuels to harvest it to get energy out. And so it
05:54
is not economically viable at this point to use some of these renewable resources. But
05:59
these are going to change over time. So if we look at oil imports in the 1990s that ratio
06:04
was 40 to 1. But if we look at oil imports in 2007 you can see that has dropped way down,
06:10
closer to around 12 to 1. And now if we look at things like wind, it has a higher ratio.
06:16
And so there is going to be a movement away from fossil fuels towards renewable resources.
06:20
And the reason why is that they are going to become cheaper. The technology is going
06:24
to improve. And the one thing that we are not even considering yet are all the externalities
06:28
of these fossil fuels. We really do not put a true value on the fossil fuels. Because
06:34
as we use them we are polluting our environment and one of the big ones is that we are increasing
06:39
the amount of carbon dioxide in the atmosphere which is leading to global change in temperature.
06:44
And so these externalities, these external costs of these fossil fuels are things we
06:49
are going to have to consider as well. So where do we move in the future? We want to
06:52
move towards renewable forms of energy. Energy that keeps coming back so we can eliminate
06:56
the energy crisis. We want them to be sustainable, be it solar or wind or sustainable biomass.
07:03
And so did you learn the following. Could you pause the video at this point and fill
07:06
in the blanks? If not, let me do it for you. So energy consumption over time was food then
07:12
we used wood. Animals. Wind. We then used coal, oil, gas. And with each of these we
07:18
have energy crisis associate with it. As we decrease supply, increase the price. And then
07:23
the last one is we really have to start considering not only the return on investment, but the
07:28
externalities. What cost do we have to society by using fossil fuels or nonrenewables.
07:33
Well, I hope you learned all of that and I hope that was helpful.


This post was previously published on YouTube.

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