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- [Instructor] Today, let's[br]talk about energy resources.

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You've probably already[br]done something today

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that used energy resources,

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even beginning from[br]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[br]step of this process.

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My car uses oil when I[br]drive to the grocery store

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to get the tea,

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my stove uses natural gas[br]when I boil the water,

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and my water heater uses[br]coal-sourced electricity

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when I wash my mug in[br]hot water afterwards.

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We use energy constantly[br]in our daily lives.

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Since the first law of thermodynamics

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states that energy cannot[br]be created nor destroyed,

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where does it all come from[br]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[br]renewable resources are

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because the prefix re means again

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and the root new refers the[br]origin of the energy source,

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so renewable energy sources

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are the sources that we[br]can use again and again

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and are quickly restored[br]by natural processes.

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Renewable fuel sources[br]include sunlight, wind,

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moving water, biomass[br]from fast-growing plants,

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and geothermal heat from the earth.

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The lifespan of renewable[br]resources looks like a circle.

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We can use them and then[br]we can use them again

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without worrying about them running out.

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Nonrenewable energy[br]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[br]be extracted from the earth,

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and they include things like[br]nuclear fuel and fossil fuels,

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which are things like[br]coal, oil, and natural gas.

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Fossil fuels were formed[br]in the geologic past

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from the remains of ancient organisms.

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Plants and animals that[br]died millions of years ago

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became buried in the soil,[br]partially decomposed,

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and were exposed to a[br]lot of heat and pressure.

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This heat and pressure[br]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[br]form, we have a finite amount

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of nonrenewable resources[br]in the earth right now.

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The lifespan for fossil[br]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[br]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[br]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[br]fuels transforms that energy

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into a less organized form[br]of energy like heat and ash.