achieving sustainability unit 3-2a understanding energy
TRANSCRIPT
ACHIEVING SUSTAINABILITYACHIEVING SUSTAINABILITY
Unit 3-2aUnit 3-2a
Understanding Understanding EnergyEnergy
Use this instead of kinetic & potential
Identify the initial & final forms of energy
Potential
Motion
Chemical
Nuclear
Gravitational
Kinetic
Motion
Electrical
Radiant
Thermal
Nuclear
Radiant
Our Planet’s Energy Resources
Energy – The ability to do work or cause a change
Potential Energy – Stored EnergyEx: chemical, nuclear, mechanical
Kinetic Energy – Energy in MotionEx: radiant, thermal, mechanical
Law of Conservation of Energy –Energy can be converted fromone form to another but itcannot be created or destroyed!
The sun converts energy…
Nuclear to Thermal and Radiant!
Where Do We Get Most Of Our Energy?
Fossil Fuels – The remains of ancient organisms; Ex:
• Petroleum (Oil),
• Coal, and
• Natural Gas
Fossil fuels &nuclear powermake up 94% ofour energy needsand are considered
Non-Renewablebecause they’re used quicker than they are replenished.
Only 6% of our current energy resources are renewable.
Our Planet’s Petroleum Supply
We use ~25 billion gallons of oil per year.
We have ~900 billion gallons remaining on Earth.
That means we have less than40 years of petroleum remainingat our current consumption rate.
Petroleum provides us with fuels;Ex: Gasoline, Diesel, Heating Oil
And many other products;Ex: Plastic, Fertilizers, Fabricsand Construction Materials
Can we imagine life without these things?
What Are Our Options?
To save our oil supplies, we could…
• Use it wisely – Hybrid cars get much better gas mileage
• Reduce consumption – U.S. fuel taxes are very low
• Find alternative resources – Corn-based products are becoming more common
• Find more oil reserves – Scientists aren’t just looking in the Earth but they’re also searching for biological sources
World Oil Reserves
Let’s Review…What have you learned in this unit?
1.Describe the difference betweenpotential and kinetic energy.
2.Describe three different typesof fossil fuels.
3.How much of our energy comesfrom renewable resources?
4.List three fuel & three non-fuelproducts made from petroleum.
5.How can we conserve ourpetroleum resources?
ACHIEVING SUSTAINABILITYACHIEVING SUSTAINABILITY
Unit 3-2bUnit 3-2b
Non-Renewable Non-Renewable EnergyEnergy
Why Do We Need So Much Fuel?
There are five main uses for fuel
• Cooking
• Transportation
• Manufacturing
• Heating & Cooling
• Making Electricity
Which fuels are for which purpose!!!!! Matching!!!
How Do We Make Electricity?
Generator – Converts mechanical energy to electricityusing magnets and an iron core
All you need is something to turn the wheel…
But it takes a lot of turningto power all of our favorite electrical devices!
We need powerful fuels(typically coal) which createsteam that turns the turbine and generator.
Which pollution problems are caused by using coal?
Cleaner? But Deadly!
Natural Gas – The fuel, mostly methane, used in homes for cooking and heating.
It doesn’t pollute the air butit creates some carbon monoxide!
Another fuel option is…
Nuclear Fission – Power plantssplit uranium atoms to createenergy for boiling water
These are both dangerous due to toxic waste and transportation issues.
Nuclear Fusion – Combines hydrogen atoms without any pollutantsbut we may never safely attain the power of the sun!
Your Carbon Footprint
Carbon Footprint – Measures the total amount of carbon released through the impact of human activities.
How much carbon is released so one person can buy a CD?Imagine all the energy needed to…
Record the CD
Create the CD
Deliver the CD
Run the store that sells the CD
Get you to the store to buy the CD
And then the energy to play the CD on your music device.
Imagine the energy needed for everything you purchase!
Let’s Review…What have you learned in this unit?
1.List four reasons that we usefossil fuel energy.
2.How does a generator work?
3.Why do we are fossil fuelsso commonly used for energy?
4.List three disadvantages to usingfossil fuels.
5.Compare and contrast nuclearfission and nuclear fusion.
REDUCING OUR FOOTPRINTREDUCING OUR FOOTPRINT
Unit 3-2cUnit 3-2c
Renewable EnergyRenewable Energy
Power from Life On EarthPhotosynthesis stores the sun’s energy in the form of…
Biomass Fuel – Renewable organic energy sources
• Wood & Dung – Commonly used in developing countries
• Methane – When it’s created by microorganisms
• Ethanol – Typically blended with fossil fuels to increase efficiency & reduce pollution
These fuels create pollution & reduce current resources!
Power from Outer Space
What is the source of all energy on Earth? The Sun!How can we use the sun’s energy?
Passive & Active Solar Heating –Uses heat from the sun to heathomes and water tanks
Photovoltaics – Cells that changesolar energy into electricity
Did you know the sun heats ouratmosphere helping us create…
Wind Power – Wind turbines arethe world’s fastest growing energy source
Where is the best place to build a wind farm in NJ?
Power from the Earth
There is a tremendous amount of energy all around us.
Just look at the power of Mother Nature!
Hydropower – Includes
• Hydroelectric Dams
• Tidal & Wave Power
There is also energy founddeep within the Earth.
Geothermal Power – Heat from the Earth’s core can boil water
How much pollution is created from these sources?
Why Not Now?
These renewable sources of energy are all viable but…
There are three major issues with renewable energy
• These energy sources are not found across the globe
• The energy produced is minimal compared to the amount that is needed
• Fossil fuels are still very profitable
However, as the environment deteriorates,our dependence on foreign energy grows,
and new technologies continue to improve,these sources will become more common.
Let’s Review…What have you learned in this unit?
1.Describe three types of renewableenergy from the sun.
2.Which three types of renewableenergy don’t create pollution?
3. Which three types of renewableenergy create air pollution?
4.Why isn’t hydropower or geo-thermal power used more in NJ?
5.Why aren’t more solar poweredcars being used in the US?