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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.