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- [Instructor] Today, let's
talk about energy resources.
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You've probably already
done something today
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that used energy resources,
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even beginning from
the moment you woke up.
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For me, the beginning of my day
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always starts with making tea.
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I use energy in every
step of this process.
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My car uses oil when I
drive to the grocery store
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to get the tea,
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my stove uses natural gas
when I boil the water,
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and my water heater uses
coal-sourced electricity
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when I wash my mug in
hot water afterwards.
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We use energy constantly
in our daily lives.
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Since the first law of thermodynamics
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states that energy cannot
be created nor destroyed,
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where does it all come from
and will we have enough?
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When we talk about energy resources,
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we could split it up into two groups:
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renewable energy and nonrenewable energy.
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I can always remember what
renewable resources are
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because the prefix re means again
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and the root new refers the
origin of the energy source,
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so renewable energy sources
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are the sources that we
can use again and again
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and are quickly restored
by natural processes.
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Renewable fuel sources
include sunlight, wind,
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moving water, biomass
from fast-growing plants,
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and geothermal heat from the earth.
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The lifespan of renewable
resources looks like a circle.
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We can use them and then
we can use them again
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without worrying about them running out.
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Nonrenewable energy
sources on the other hand,
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are sources that exist in a fixed amount
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and cannot be easily replaced.
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These energy sources must
be extracted from the earth,
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and they include things like
nuclear fuel and fossil fuels,
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which are things like
coal, oil, and natural gas.
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Fossil fuels were formed
in the geologic past
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from the remains of ancient organisms.
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Plants and animals that
died millions of years ago
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became buried in the soil,
partially decomposed,
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and were exposed to a
lot of heat and pressure.
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This heat and pressure
chemically rearranged
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the energy contained within their bodies
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into the fossil fuels we use today.
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Because they take so long to
form, we have a finite amount
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of nonrenewable resources
in the earth right now.
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The lifespan for fossil
fuels is a broken loop,
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a one-way ticket.
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First, the fossil fuel is found,
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then it has to be extracted.
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Extracting fossil fuels
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can involve destructive mining processes
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that can pollute surrounding habitats.
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It then has to be transported
to wherever it will be used.
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And using fossil fuels means burning them,
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which releases greenhouse gases
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and other pollutants into the atmosphere.
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Also, it can take energy
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to refine and process
some types of fossil fuel
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so that they're more helpful to us,
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like turning crude oil into petroleum gas,
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diesel, and jet fuel,
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and burning the fossil
fuels transforms that energy
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into a less organized form
of energy like heat and ash.