Global Environmental Change: Causes and consequences regarding natural and social systems

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Energy
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Energy ability to do work
Work force x distance (Fd) Force mass x
acceleration (ma) Therefore, Work is mad.
Energy is conserved, Always! (1st law) -but can
change form from potential to kinetic
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Basic principles
Tire has gravitational potential energy. As it
swings it drops, so loses some potentialPotential
converted to kinetic Maximum speed at
bottom Then converts back to gravitational
potential. Only the difference in height at top
and bottom Does not swing forever. Air
resistance and friction convert kinetic to heat
(2nd law)
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Converting energy
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ENERGY SOURCES
Fossil fuels Oil, Gas, Coal, Uranium Renewable
sources Biofuels, other? Inexhaustible
sources Solar, Wind, Hydro, Fusion?
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Energy Sources and Consumption U.S. SOURCES
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U.S. CONSUMPTION
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Units of Measure
Energy ability to do work Work is mad, yet
logical
Force mass x acceleration (ma) - Newtons Work
(energy) force x distance (Fd) - Joules 1
Joule/sec 1 Watt (work per time is power) You
buy energy (J), typically in kW-hours 1018 J 1
exojoule 1015 BTU 1 Quad U.S. uses 100 Quads
per day
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HOUSEHOLD ENERGY USE
APPLIANCE WATTS ANNUAL (KW/yr) Clothes
Dryer 4600 1050 Light bulb 100 100 Fluorescent
23 23TV 350 500? Computer 600 2000? Water
heater 4500 4700 Toaster 1200 550 Refrigerator
360 2160
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Energy Efficiency
Efficiency is defined by 1st and 2nd laws of
thermodynamics 1st law efficiency is energy
provided per energy consumed. 2nd law efficiency
is minimum energy needed per energy
consumed Important difference! Dont need
nuclear reactor to heat a house. For home
heating, only need 70F or so not 1800F!
Passive solar would do. 1st law Waste heat
2nd law Incandescent bulb 5 95 Fluorescent 2
0 80 Automobile 20-25 75-80 10 Power
plants 30-40 60-70 30 Heating w/fossil
fuel 2-6 All U.S. energy 50 50 10-15
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CONSERVATION
Energy efficiency achieved by minimizing
high-quality energy use to do work In electric
power plants, use waste heat to heat buildings
(cogeneration) Most energy is used for heating,
industry and transportation - So focus
conservation efforts in those sectors.
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Building design

• Green architecture involves many
  characteristics
• US Green Building Council (USGBC)
• Leadership in Energy and Environmental Design
  (LEED)
• Rating system based on
• Site selection (brownfield redevelopment,
  transportation, etc.)
• - Water efficiency
• Energy efficiency
• Building materials (reuse, recycle)
• Indoor environment
• Innovative design

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Library in hot climate
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CAFE standards regulate industry
production (Corporate Average Fuel Economy) 1)
Passenger Car any 4-wheel vehicle not designed
for off-road use that is manufactured primarily
for use in transporting 10 people or less. 2)
Truck a 4-wheel vehicle which is designed for
off-road operation (has 4-wheel drive or is more
than 6,000 lbs. GVWR and has physical features
consistent with those of a truck) or which is
designed to perform at least one of the following
functions (1) transport more than 10 people
(2) provide temporary living quarters (3)
transport property in an open bed (4) permit
greater cargo-carrying capacity than
passenger-carrying volume or (5) can be
converted to an open bed vehicle by removal of
rear seats to form a flat continuous floor with
the use of simple tools.
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Policy can regulate use, production, and
especially RESEARCH.
110 billion spent on RD from 1949-1999 60 to
nuclear 20 to fossil fuel 11 to renewables 7
to energy efficiency 2 Billion/yr spent on
energy RD in 1990s 45 Billion/yr spent on
military RD in 90s
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Hard Path ensure energy availability Soft Path
maximize efficiency, renewables
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Centralized vs. distributed energy production
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Fossil Fuels
Today, coal provides about 60 of the U.S.
electricity supply and the U.S. imports more than
half of the oil it consumes. The burning of
fossil fuels cannot be sustained.
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Fossil fuels are not renewable. We are
increasingly depending on fossil fuels to fulfill
our growing energy needs. They WILL run out
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Fossil Fuels formed by decomposition (reduction,
not oxidation) of organic material Mostly algae
and plants. Mostly marine microbes (not
dinosaurs!) 90 of global energy comes from
fossil fuels
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Oil
Black Gold Texas Tea
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Oil comes from decomposition of organic material
(mostly phytoplankton) in an anoxic environment.
It matures by losing Oxygen and retaining
carbon and hydrogen - ergo, hydrocarbons. Oil
is lighter than water, so rises in sedimentary
rocks to become trapped in reservoirs.
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Oil reserves include resources that can be
extracted and sold at a profit. (thus reserves
seem to increase as prices rise) - Dont be
fooled! Oil requires hundreds of millions of
years to form. NON-renewable. (billion barrels)
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Where oil comes and goes (Million metric tons)
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• 2 issues
• How long until we run out?
• 2. How long until we peak out in production rate?

Peak expected in 2020-2050 (soon!). Then expect
shortages, price instability, depressions, war
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Oil is too valuable to burn! We need it for
petrochemicals, plastics, etc. High-quality
energy should not be used for burning (2 law
inefficiency) Strategy Use present global oil
economy to support research and development of
next generation of energy sources. Must do this
BEFORE production peak!
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Issues
Will new recovery methods make more oil available
in the future? Will this change the timing of
peak production? Present reserves are about 1
trillion barrels out of total 3 trillion. Present
pumping rate of 27 billion barrels/yr (gives 37
yrs, or 111 yrs) We use up oil at 3-4 times the
rate we find more. Peak production time is based
on recovery of oil yet to be found. Business as
usual will deplete all oil by about 2100.
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Natural Gas (Methane)
Methane is highly matured hydrocarbon with a
maximum ratio of HC CH4 Burns cleaner that other
hydrocarbons, with max energy per carbon Not
considered valuable (Nuisance gas on top of
useful oil- burn it off!) Without just throwing
away, present use will deplete reserves in 70-120
yrs Associated with oil, and also with
coal Coal bed methane recovery leads to
environmental problems from salt water
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Methane Hydrates
Methane molecule trapped in water ice
structure Forms at 1000 m ocean depth in narrow
P-T window HUGE amount of methane stored along
continental margins (Twice all other fossil
energy sources combined) But- Dont know how to
drill for it yet In geologic past, BIG methane
releases resulted from climate change. Will it
happen again?
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Environmental Impacts

• Oil and Gas Recovery
• Direct land use at well site (or offshore rig)
• - Disrupts local ecosystems (e.g. Alaska)
• Water pollution from well site (oil, salt)
• Air pollution
• Subsidence due to extraction of subsurface
  fluids
• Oil spills
• Refining
• Fractional distillation separates components of
  crude oil
• - then make gas, diesel, petrochemicals
• Major air and water pollution impacts
• Delivery and use
• Oil spills from tankers
• Leaks from pipelines
• Pollution and Greenhouse warming

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Alaska
Senate decided recently to allow drilling in
national wildlife refuge (some refuge!)
Why not drill in Alaska? Because the last
country with oil under its feet WINS! Like
spending our money in the bank when while we can
still use other peoples
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Coal
Oil forms from removal of oxygen from organic
material. Further maturation increases ratio of
H to C to make natural gas. When both H and O
are lost from organic material, only C remains-
COAL! Most abundant fossil fuel. Also most
effective at increasing greenhouse. Enough to
last 250 years at current use. Anthracite-
purest, hardest, densest, most energy-producing
coal (in PA!) Bituminous- soft coal, with some
impurities. Less energy per pound Subbituminous-
softer still Lignite- Softest, lightest, with
most volatiles and least energy Peat- Not quite
coal (yet). Famous in Ireland.
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Coal reserves
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U.S. Coal
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Environmental impacts of Coal
Ugly strip mines Acid Mine Drainage- Makes
sulfuric acid that enters streams. Kills life.
River in PA
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Treatment of Acid Mine Drainage
Divert streams away from mine spoil banks Use
alkali materials like limestone to raise pH in
treatment plants Passive treatment open
channel limestone (dissolved limestone increases
pH) artificial wetlands (only for alkali water,
to precipitate metals) diversion wells filled
with limestone Pyrolusite process uses microbes
injected into limestone channels to precipitate
metals and etch limestone to raise pH.
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Whats up with coal?
Coal provides 60 of electricity for U.S.! (25
of total energy) 90 of U.S. fossil fuel is coal
- so we will probably use as least some of
it. Atmospheric pollution is big problem PA DEP
suing federal EPA over regulations. - Different
rules in PA and western U.S.- Why? How to
improve utility of coal? clean it before you
burn it burn at lower temperature to reduce NOx
emission add expensive scrubbers to smokestacks
(then deal with the sludge) coal
gasification What if China really starts burning
it vast reserve of coal? - Major CO2 problem!
Global greenhouse issues.
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• Oil Shale
• Shale that contains oil (kerogen) in tiny pore
  spaces
• - Heating extracts oil from the rock
• - Expensive process
• Tar Sands
• Sand with oil (or tar, or bitumen) in pore spaces
• cannot pump because oil is too viscous (thick)
• - Most tar sands in Canada

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• Is U.S. gas tax sufficient?
• For what?
• a) Deterrent from use
• b) Funding of alternative energy research

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Tax per gallon on gasoline