Transcript Document

Energy Efficiency and
Renewable Energy
G. Tyler Miller’s
Living in the Environment
14th Edition
Chapter 18
Chapter 18 Key Concepts
Improving energy efficiency
Types and uses of solar energy
Types and uses of flowing water
Uses of wind energy
Types and uses of biomass
Use of geothermal energy
Use of hydrogen as a fuel
Decentralized power systems
Section 1: The Importance of
Improving Energy Efficiency
• What is energy efficiency? How
much energy do we waste?
• What is life cycle cost?
• What is net energy efficiency?
What is energy efficiency?
Energy efficiency is the
measure of the useful
energy produced
compared to the energy
converted to low quality-- usually heat.
Using energy to do work,
not produce heat.
What is energy conservation?
Implementing new
technology to do same
work using less energy.
• Heating homes more
efficiently
• Driving more efficient cars
• Lightning spaces more
efficiently
SAVES $$$, produces
less pollution, reduces
CO2
Energy Conservation
• 84% of commercial
electricity is wasted in
U.S.
• 41% of energy is
automatically wasted
due to 2nd Law Of
Thermodynamics
• 43% is wasted
unnecessarily
Advantages of Reducing Energy
Waste
The Importance of Improving Energy
Efficiency
 Energy efficiency
 Net energy efficiency
Least Efficient
 Incandescent lights
 Nuclear power plants
 Internal combustion
engine
Fig. 18-3 p. 381
Energy Efficiencies (Fig. 18-5 p. 381)
Life Cycle Costs
Initial Cost plus the
lifetime cost.
Some energy efficient
models may cost more
up front, but save
money in the long run.
Civic Hybrid vs.
Conventional Gas
Net Energy Efficiency
Measure of how much
useful energy we get
from energy resource
after subtracting the
energy wasted.
How much energy you get
out given ALL the
wasted energy.
Comparing Efficiency of 2 Types
of Space Heating
Section 2: Ways to Improve
Energy Efficiency Key Concepts
• How can we save energy in industry?
• How can we save energy in transportation?
• How can we design buildings to save
energy?
• How can we save energy in existing
buildings?
• Why are we still wasting so much energy?
Ways to Improve Energy Efficiency
Cogeneration
Efficient electric motors
High-efficiency lighting
Increasing fuel economy
Alternative vehicles
Insulation
Plug leaks
How can industry save energy?
• Cogeneration –
combining heat and
power systems
• Improving electric
motor efficiency
(consumes 1/4th of
energy)
• Improving light fixtures
How can we save energy in
transportation?
CAFÉ Standards need to
be increased.
Increase to 40 mpg in
10yrs would cut
consumption in half
(could eliminate
imports from Middle
East)
Average Fuel Economy of New
Vehicles Sold In U.S.
Price of Gas in 1993 Dollars
Hybrid and Fuel Cell Cars
 Hybrid electric-internal combustion engine
Hybrid-electric
cars are powered
by a battery and
a small ICE that
recharges the
battery.
Fig. 18-9 p. 385
Toyota Prius
Ford Escape Hybrid
Fuel Cell Cars
Fuel cell cars run on
hydrogen and produce
little pollution.
Combine hydrogen and
oxygen to produce
electricity and water
vapor.
Ford Focus Fuel
Cell Car
Fuel Cells
GM’s prototype future fuel cell car. No engine noise, no
pollution, no greenhouse gasses.
How can we Design More
Efficient Buildings?
Chicago’s Sears Tower
uses more energy in a
day than a city of
150,000
Atlanta’s Georgia Power
Company uses 60% less
energy than other
buildings it size.
How can we Design More
Efficient Buildings?
We can save energy in
buildings by
• Getting heat from the
sun
• Insulating well
• Using plants for shade
and wind blockage
How can we Design More
Efficient Buildings?
Super insulated house:
• Costs 5% more to build
• Can use 90% less
energy for heating and
cooling
Green Roofs:
• Plants or gardens on
roof help insulate from
heat in summer and
cold in winter
An infrared photo showing heat loss (red,
white and orange) around windows, doors,
roofs.
How can we save energy in
existing buildings?
We can save energy in
existing buildings by:
• insulating them
• plugging leaks
• using heating,
electricity, cooling,
appliances and lighting
more efficiently
Insulate and plug leaks
1/3rd of heated air in U.S.
homes is lost through
windows, holes and
cracks.
Insulating and plugging
holes is the easiest and
cheapest ways to save
energy.
Use Efficient Windows
Double pained,
insulating windows
cost more, but can
save money in the
long run.
Heat House More Efficiently
Using the most efficient
heating system
available.
Some natural gas furnaces
can reach 85-98%
efficiency
Heat Water More Efficiently
There are several new
technologies to heat
water more efficiently:
• Tankless, instant heaters
• Well insulated tank
Use Energy Efficient Lighting and
Appliances
Microwaves,
refrigerators, washers,
driers, lights all come
with energy star labels
¼ of electricity bill is
lighting
Cut Off Electrical Devises Not In
Use
When not using lights,
computers, TV’s and
other electrical
devises they should
be turned off.
Review Section 2
• How can we save energy in industry?
• How can we save energy in
transportation?
• How can we design buildings to save
energy?
• How can we save energy in existing
buildings?
• Why are we still wasting so much
energy?
Section 3: Producing Energy
With Solar Power: Key Ideas
• What are the main types of renewable energy?
• How can we use direct solar energy to heat and
cool homes?
• How can we use solar energy to produce
electricity?
• What are solar cells?
• What are advantages and disadvantages of
solar cells?
What are the main types of
renewable energy?
The next several sections
we will go through:
• Solar Energy
• Flowing Water
• Wind
• Biomass
• Geothermal
• Hydrogen
• Other possible renewable
energy sources.
What are the main types of
renewable energy?
• EU by 2020: 22%
renewable
• CA gets 12% from
renewable (20% by
2020)
• Union of Concerned
Scientists study said
20% by 2020 is
possible
Using Solar Energy to Provide Heat
Passive solar heating: absorbs and stores
heat from the sun directly within the structure
Has been used for thousands of years.
Using Solar Energy to Provide Heat
Active Solar: absorbs heat
energy from sun by
pumping heat absorbent
fluid through collectors.
Great for hot water
heaters in warmer
climates
Using Solar Energy for Electricity
Solar energy can be
converted directly into
electricity using
PHOTOVOLTAIC
CELLS (PV) or “Solar
Cells”
Sunlight energizes electron
to flow in a semi conductor
producing an electrical
current
Using Solar Energy for Electricity
Solar Cells can be
incorporated into
roofing and windows.
High costs are
expected to fall
Currently only supply
0.05% of world
electricity
Using Solar Energy for Electricity
Great for rural locations
BP in 2004 began to mass
produce cells
With increased R&D and
government help --- 25%
by 2040???
Using Solar Energy for Electricity
Solar Thermal Systems:
large solar arrays in
sunny areas can
produce hightemperature heat for:
• Electricity
• Hot water
• Heating
• Wash Machines
Using Solar Energy for Electricity
 Solar thermal systems
 Photovoltaic (PV) cells
Producing Electricity From the
Water Cycle: Section 4 Key
Concepts
• How can we produce electricity from
flowing water?
• What are advantages and disadvantages
of hydropower?
• What is tidal and wave power?
Producing Electricity from Moving Water
 Large-scale hydropower
 Small-scale hydropower
 Pumped-storage hydropower
 Tidal power plant
 Wave power plant
Renewable Hydropower
Water flowing in rivers
and streams can be
trapped in reservoirs
behind a dam and
released to spin turbines
to produce electricity.
In 2002, hyrdro accounted
for 20% of world
electricity (Norway
99%, U.S. 7% -- 50% in
west)
Renewable Hydropower
According to UN only
13% of potential
hydropower has been
developed
Large Scale Hydro Power
has been curtailed
recently by
environmental concerns
Largescale
Hydroelec
tric
Power:
Trade-offs
Reviewing the Trade-offs of
Hydropower Dams
Fig. 15-9 p. 313
Hoover Dam
Tidal Power
Using the twice daily
natural rise and fall of
tidal waters to produce
power.
Newer concept
Lot of potential in certain
tidal regions.
Problems???
Tidal Power
Wave Power
Using the constant wave
action along shorelines
to produce power.
Another form of wind
power.
Problems???
Producing Electricity from Wind
Section 5 Key Concepts
Producing Electricity from Wind
Fig. 18-23 p. 396
Fig. 18-24 p. 397
Altamont Pass California
Atlantic City
http://www.eere.energy.gov/windandhydro/windpoweringamerica/where_is_wind_n
ew_jersey.asp
Producing Energy from Biomass
Biomass and biofuels
Biomass plantations
Crop residues
Animal manure
Biogas
Ethanol
Methanol
Fig. 18-25 p. 398
Geothermal Energy
Geothermal heat pumps
Geothermal exchange
Dry and wet steam
Hot water
Molten rock (magma)
Hot dry-rock zones
The Hydrogen Revolution
Environmentally friendly hydrogen
Extracting hydrogen efficiently
Storing hydrogen
Fuel cells
The Hydrogen Revolution
Fig. 18-31 p. 403
Entering the Age of Decentralized
Micropower
 Decentralized power systems
 Micropower systems
Fig. 18-32 p. 405
Solutions: A Sustainable Energy
Strategy
Fig. 18-35 p. 407