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Hi. It's Paul Andersen and welcome to disciplinary core idea PS3D. This is on
energy in chemical process and everyday life. To really understand energy you need to understand
how it can be converted from one form to another. So where is the energy in this motorcycle
coming form? Where was it before it was in the motorcycle? And where does it go when
it's done? And so I was on ExxonMobil's website the other day and they had a whole section
on producing energy. And that's not really true. They're not really producing energy.
Likewise I was on PBS's website and they had a video series entitled using energy. And
that's not really correct either. Both of them are really talking about converting energy.
Because energy can't be created nor destroyed. It can be converted from one form to another.
And so we really need to understand how that works. As so where's my energy coming from?
Where is the energy of my thinking and moving and talking and all of that. Where does that
energy come from? Well it comes from my food. I like to eat granola for breakfast. And where
is the energy in granola come from? Well granola is rolled oats and honey. Where is the energy
coming from there? Well the rolled oats, the oats are getting their energy through photosynthesis.
What about the honey? Well honey comes from bees, which come from clover, which is another
plant. And so where is the real energy coming from? It's coming from the sun through this
process of photosynthesis. And so I'm just simply converting the energy. And when I'm
done with it, a lot of it eventually is going to end up as heat. Likewise with that motorcycle,
where is it's energy coming from? It comes from its gasoline. But where did the energy
sit before that? It was in crude oil. And before that, where do oil and fossil fuels
get their energy? Well they're built over millions and millions of years from ancient
rain forests that were covered up in soil. And so we're back to plants again. And we're
therefore back to the sun again. And so really what's happening is we're simply converting
that energy into another form. And all energy eventually is going to end up in a real low
ordered energy called heat. And so when we're thinking about power generation, making energy
for us to use or converting energy for us to use, there's many different forms. From
coal to oil, natural gas, nuclear, solar, wind, geothermal, hydro power, there's lots
of ways we can make our energy. Now some of these are what are called fossil fuels. I
would put coal, oil and natural gas with that. What does that mean? They've been produced
over millions of years from ancient organic material. Some of these are more sustainable,
like wind, solar, geothermal. But you should know this. That all forms of electricity generation
and transportation have certain costs and benefits, be it economic, social & environmental.
And so it's hard to say this is what energy form we should use. Because there are going
to be benefits and drawbacks on all of these. Clearly we would like to convert to more sustainable
forms of energy. But right now we're stuck with a lot of fossil fuels. And so what we
really have to do is come up with efficient designs. And what does that mean? The energy
into a system is going to be used to do work. But a lot of it is going to be lost through
heat. And so the less amount of energy that we can lose to heat, the more efficient that
system can be. And so when you're designing something like an airplane, you want to make,
or a jet plane, you want to make sure that it is as efficient as it can be. We want it
to be really, really light and aerodynamic. So it's not going to lose energy due to frictional
loss. And so how do we teach this is schools? Well starting with our lower elementary grades
we want them to understand that friction generates heat. If you ever have two objects that are
in contact and moving around in relation to each other, it generates a little bit of heat.
And so we need to know that we can reduce the amount of heat that's being proceeded.
And so putting oil on a chain on your bicycle means that you're going to lose less energy
due to frictional loss. And it's actually going to be easier for you to ride that bicycle.
As we move into the upper elementary grades we want to start talking about this idea of
energy conversion. And staying away from energy use or energy production. We're simply converting
it from one form to another. And so where does food get it's energy? Again it originally
came from plants. Where does gasoline get it's energy? It gets it from fossil fuels.
So its used to be forests. And even the energy that's stored in a dam, well, how did the
water get above the dam? It was the water cycle. And it was heating of the sun that
caused that energy to move up or the water to move up and store that energy right there.
We also want to talk about energy and making sure it's in the right area. So batteries
are wonderful because they can make energy available to us. And if we can increase the
amount of efficiency of out batteries, we can do better work. Likewise, moving energy
from one location to another is really difficult. We can generate it in a solar wind farm, but
how do we get it to your house? How do we get it to my computer right now? We need to
make systems that are as efficient as possible. As you move in to middle school you want to
talk about photosynthesis and respiration. You really want to talk about in general terms.
You don't have to go through the steps of that. But how does photosynthesis work? We're
taking energy from the sun. Converting carbon dioxide and water into sugars and oxygen.
So that oxygen is given off in photosynthesis. Likewise how do we convert that energy. Well
we're going to take in that sugar and oxygen using respiration and convert that to carbon
dioxide and water. We can generate energy there. And so most of my energy right now
is coming from cellular respiration. All of my energy right now is coming form cellular
respiration. We also want them to understand the importance of design. And through proper
design we can increase the efficiency of a system or a machine for that matter. And make
sure that we're using as much of that energy as possible. Finally as we get into high school
we want to understand that that energy coming from the sun is energy that is being produced
through nuclear fusion. And so it's a fusion reactor. Now it's millions of miles away,
but it's producing energy that we can use. Plants have figured this out over years using
photosynthesis. They can harvest that energy. And we're learning that as well. So using
simple solar cells, we can harvest energy from the sun and use that. And so in the future
we're going to try to convert from more fossil fuels to more sustainable energy. And where's
a great place to get a lot of that energy from? It's the sun. But it all depends on
efficient design so we can harvest as much of that energy we can before it's converted
to heat. And I hope that was helpful.