Transcript Document

Energy Efficiency and
Renewable Energy Resources
Solutions:We have the answers!
Energy Efficiency!
43% of energy in the US is wasted
unnecessarily
• Incandescent bulb=5% efficient
Fluorescent bulb=20% efficient
• Auto fleet standards = CAFE Standards
(Corporate Average Fuel Economy)
– 12.9 mpg in 1974
– 27.9 mpg today
– 40 mpg CAFE standard would cut gas use by 50%
Efficiencies
Ways to Improve Energy Efficiency
Insulation
Eliminate air leaks
Air to air heat exchangers
Efficient appliances
Efficient electric motors
High-efficiency lighting
Increasing fuel economy
Solutions:We have the answers!
Renewable Energy Resources!
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Biomass
Hydroelectric power
Geothermal
Solar—passive and active
Wind generation
Hydrogen power
Using Solar Energy to Provide Heat
and Electricity
Passive solar heating
Active solar heating
Using Solar Energy to Provide HighTemperature Heat and Electricity
Solar Cell Trade-Offs
 Solar thermal systems
 Photovoltaic (PV) cells
Producing Electricity from
Moving Water
 Large-scale hydropower
 Small-scale hydropower
50% of West Coast electricity
7% of US electricity
20% of World’s electricity
Major environmental impacts
High construction costs
Impacts of hydropower on salmon
and other riverine spp.
 Pollution
 Disruption of
water flow
 Loss of
biodiversity
 Invasive species
Impacts of hydropower on
Species and People_______________
Dams can provide many human benefits but:
• Disrupts ecological services rivers provide;
e.g. 119 dams on Columbia River have
caused a 94% drop in wild salmon; removing
hydroelectric dams will restore native
spawning grounds
• Displaces millions of people worldwide as
reservoirs flood traditional homelands
• No room for expansion in the US
Producing Electricity from Wind
Producing Energy from Biomass
Biofuels
Biomass plantations
Crop residues
Animal manure
Biogas
Ethanol
Methanol
The Solar-Hydrogen Revolution
Extracting hydrogen efficiently
Storing hydrogen
Fuel cells
Geothermal Energy
Geothermal reservoirs
Dry steam
Wet steam
Hot water
Molten rock
Hot dry-rock zones
Geothermal Reservoirs
Entering the Age of
Decentralized Micropower
Centralized power systems
Decentralized power systems
Micropower systems
Fig. 16-39
p. 411
Creating a Sustainable Energy Future
• Increase fuel efficiency standards for
vehicle, appliances, buildings
• Tax and other financial incentives for
energy efficiency
• Subsidize renewable energy use,
research and development
• Internalize externalities for fossil fuels
• By 2050:
– Increase renewable energy to 50%
– cut coal use by 50%
– phase out nuclear altogether
Solutions:
A Sustainable Energy Strategy