Transcript Energy – Where does it come from and why does it produce waste?

With your closest table mates:
Write the answer to your assigned question
up on the board.
Remember to show work!
HOMEWORK CHECK
Resources & Reserves
Resources ≠ Reserves
• Resources – amounts of material that are
known/ assumed to exist that can be
extracted NOW or in the FUTURE for a
POSSIBLE profit $
• Reserves – known amounts of material that
can PRESENTLY be extracted for a PROFIT
– “proven”
Changing estimates
• Why do reserves of resources usually last
much longer than most early estimates
predict?
• How does technology influence the estimates of
reserves and resources?
Resource Depletion
static, exponential, real world
Energy –
Where does it come from?
ES 302
Objectives
• What is energy?
• What forms does it come in & how do we use it?
• Understand that ALL sources of energy have costs
and benefits
What is Energy?
• Energy “The ability to do work”.
• Remember:
The amount of energy in the universe is constant.
What are the 2 major laws???
- 1st and 2nd Law of thermodynamics
What are the 6 major forms?
- light, chemical, nuclear, mechanical, electrical, heat
Energy Resources
• Renewable Energy
–
–
–
–
–
–
Hydroelectric
Wind
Solar
Biofuels
Hydrogen fuel cell
Geothermal
• Nonrenewable Energy
– Oil
– Coal
– Natural gas
What is your guess?
Fossil fuel power
Nuclear power
Wind / solar power
Hydroelectric power
1. Out of the energy sources above, which is used
the most worldwide? Least?
2. Guess what percentage each source contributes
to the world’s energy supply.
3. Create a graph.
Worldwide energy sources
7% 2%
7%
fossil fuel
nuclear power
hydroelectric
power
wind and solar
power
84%
Can you make 2 observations regarding energy and
electricity generation?
Can you make it work?
• What is causing the ball to light up?
• Where is the power coming from?
Can you light the lightbulb?
• Make a circuit = energy CIRCLE
What is electricity?
• The movement of
electrons.
• Created by moving wires
(electrons) through a
magnetic field.
Energy is needed to make electricity
• Where does the supply of electrons come from?
http://www.youtube.com/watch?v=3RzN7T5xpVc
• Can you list the steps to create electricity?
Electricity Production
•
Coal/oil/natural gas fired power plants
1. Burn fossil fuel to make heat.
2. Heat boils water to make steam.
3. High pressured steam turns a turbine.
4. Moving turbine spins a magnet within wires (generator).
5. The magnet creates a flow of electrons = Electricity!
6. Moving electrons sent through wires to houses, schools,
etc.
•Can you order the pictures correctly?
What is a watt?
• 1 watt = energy to lift 100 g (or 1 Newton) in
1.0 seconds.
• It is a measure of energy over time
Other Units of Energy
• 1 calorie
• 1 Btu (British thermal unit)
• 1 Q (quad) = 1 quadrillion Btu (very large!)
– The U.S. uses ~ 1 quad of energy about every 3.7
days
• 1 kWh = one kilowatt of electricity over 1 hour
Extra Resources
2nd set of notes on Energy:
Usage & Quality
It takes energy to get energy
•
Before it’s useful…
Oil must be 
1.
2.
3.
4.
5.
6.
Found
Pumped
Transported
Refined
Transported
burned
Net energy
• Total useful energy available from the
resource over its lifetime minus the amount of
energy used and wasted
• Example:
– 10 units of energy in oil in ground
– Use 8 units to find, extract, process, transport
– 2 units of net energy available
Energy Quality
• The measure of the energy’s ability to be used
to produce mechanical or electrical energy
• Low temperature heat has the LOWEST quality
– You can’t cook with it, you can’t move anything
with it, you can’t even heat with it
– Power plants are designed to release it into space
Do you have
any vampires in
your house?
How can
changing a light
bulb reduce
greenhouse
gases?
Energy Efficiency
• Amount of energy that gets converted to
useful energy.
CFL – compact fluorescent lightbulb
Incandescent
life span: 1,500 hours
Watts:
60
CFL
10,000 hours
14
Over the course of 30 years, having CFL lightbulbs in
your house can save you around $20,000!
Two sides to everything.
http://www.mnn.com/earth-matters/translating-uncle-sam/stories/cfl-vs-incandescent-battle-of-the-bulb
Byproducts of electrical generation
• Burning coal
Air: Mercury, CO2, SO2, NO2, fly ash
Water: thermal pollution, acid rain
Ground: bottom ash
Example of the Laws of Conservation of Matter
and Thermodynamics
Global Warming
Acid Rain Smog
Burning Coal = CO2 + SO + H20 + Ash +
(CxHxSxOx)
Light + Noise + Heat
Matter cycles, energy flows
Cartoon: http://www.youtube.com/watch?v=V1O34cqerqs
Mini-FBL lesson
What processes involve the transfer of
carbon?
Carbon Cycle Drawing
• Make your own, UNIQUE, drawing
of the carbon cycle (both land and
ocean). Include the following:
– Photosynthesis, decomposition,
respiration, combustion, diffusion,
(LABEL ALL)
– Include yourself somewhere in the
cycle
– Point out where humans
interfere/alter the carbon cycle
What is our best immediate energy option?
1. Cut out unnecessary energy waste by
improving energy efficiency
2. Transition to a renewable or solar age
– Sun, wind, flowing water, biomass, geothermal,
hydrogen gas
3. Burn more coal & synthetic gas/liquids
4. Natural gas
5. Nuclear power
No matter
what our
decision…
Ask:
• How much will be available in the
next 15 years? the next 30 years?
longterm?
• What is the source’s net energy
yield?
• How much will it cost to develop,
phase in, and use this energy
resource?
• How will extracting, transporting,
and using the energy resource
affect the environment?
• Can this energy source help us
sustain the earth?
• http://www.youtube.com/watch?v=1xPjESsHwg&feature=related
– Very slow explanation of current & voltage. Nice
analogy to water (river, lake)
• http://www.youtube.com/watch?v=k7Sz8oT8
ou0
– Cardboard generator constrxn (7:44)