(Fig. 18-5 p. 381) Ways to Improve Energy Efficiency Cogeneration
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Transcript (Fig. 18-5 p. 381) Ways to Improve Energy Efficiency Cogeneration
Energy Efficiency and Renewable
Energy
G. Tyler Miller’s
Living in the Environment
14th Edition
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
The Importance of Improving Energy
Efficiency
Energy efficiency useful
vs. loses to low quality heat
Net energy efficiency
Least Efficient
Incandescent lights
Nuclear power plants
Internal combustion
engine
84% of all U.S. energy is
wasted
Fig. 18-3 p. 381
Energy Efficiencies (Fig. 18-5 p. 381)
Ways to Improve Energy Efficiency
Cogeneration
Efficient electric motors
High-efficiency lighting
Increasing fuel economy
Alternative vehicles
Insulation
Plug leaks
Overview
•Hydrogen is not a primary source of energy, unlike petroleum.
Hydrogen is used to move energy.
•The prospect of clean hydrogen fuel-cell vehicles creates a
sustainable environment without compromising extreme
personal mobility.
Overview
•Fuel cells convert hydrogen gas into
electricity cleanly, making
possible nonpolluting vehicles
powered by electric drive
motors.
• A chicken-and-egg problem exists:
large numbers of fuel-cell
vehicles require adequate fuel
availability to support them,
but the required infrastructure is
hard to build unless there are
significant numbers of fuel-cell
vehicles on the roadways.
•Despite steady improvements, today’s vehicles are only up
to 25% efficient in converting the energy content of
fuels into drive-wheel power. (expected to plateau
around 30%)
•Hydrogen fuel-cell vehicle is nearly twice as efficient, so it
will require just half the fuel energy.
•Of even more significance, fuel cells emit only water and
heat as by-products. Finally, hydrogen gas can be
extracted from various fuels and energy sources, such
as natural gas, ethanol, water (via electrolysis using
electricity) and, eventually, renewable energy systems.
Hybrid and Fuel Cell Cars
Hybrid electric-internal combustion engine
Fuel cells
Fig. 18-9 p. 385
Octane 100
Octane 120
6 lbs of CO2 per gallon!
This breaks bonds to make energy
2 H2
1 O2
2 H2O
0 lbs of CO2 per gallon!
This makes bonds to release energy!
Using Solar Energy to Provide Heat
Passive solar heating
Active solar heating
Fig. 18-16 p. 391
Using Solar Energy to Provide HighTemperature Heat and Electricity
Fig. 18-21 p. 395
Solar thermal systems
Photovoltaic (PV) cells
Fig. 18-20 p. 394
Producing Energy from Biomass
Biomass and biofuels
Biomass plantations
Crop residues
Animal manure
Biogas
Ethanol
Methanol
Fig. 18-25 p. 398
Producing Electricity from Moving Water
Large-scale hydropower
Small-scale hydropower
Pumped-storage hydropower
Tidal power plant
Wave power plant
Reviewing the Trade-offs of
Hydropower Dams
Fig. 15-9 p. 313
Large-scale Hydroelectric Power:
Trade-offs
Fig. 18-22 p. 396
Producing Electricity from Wind
Fig. 18-23 p. 396
Fig. 18-24 p. 397
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