Energy is the ability to do work and transfer heat It comes in many forms light heat electricity mechanical nuclear Energy Terms Kinetic Energy Matter that has energy because of its mass and speed ID: 698230
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Slide1
Unit VII
EnergySlide2
What is energy?
Energy is the ability to do work and transfer heat.
It comes in many forms:
light
heat
electricity
mechanical
nuclearSlide3
Energy Terms
Kinetic Energy
Matter that has energy because of its mass and speed.
Electromagnetic Spectrum
Represented as wavelengths of sounds, light, and radiation.
Heat
Total kinetic energy of all moving atoms, ions, or molecules of a substance
Temperature
Measurement of the average speed of those particles.Slide4
Energy Terms
Potential Energy
Stored energy that has the potential to do work.
High quality energy
Organized or concentrated to perform useful work
fossil fuels
Low quality energy
Dispersed and disorganized and has little ability to do work.
Atlantic OceanSlide5
Energy Terms
Entropy
Measurement of the disorder of energy.
Higher entropy = less useful
Physical Change
Changes in shape, size, form, etc. without chemical alteration
Mixture of eggs, milk, and flour
Chemical Change
Chemical reactions that alter the composition of mixtures or compounds.
Adding heat to batter makes a cakeSlide6
Energy Terms
Nuclear Change
Nuclei of certain isotopes change into one or more different isotopes.
Radioactive Decay
Unstable isotopes (radioisotopes) are emitted as fast-moving or high-energy radiation or both.
alpha or beta particles or gamma rays
Continues to decay until unstable isotope becomes stable isotope.
Measured as half-life
Radiocarbon dating
Used to estimate the age of carbon-containing matterSlide7
Energy Laws
1
st
Law of Thermodynamics
(AKA: Law of Conservation of Energy)
Energy is neither created nor destroyed
But it may be converted from one form to another.
So why worry about the loss of resources?
2
nd
Law of Thermodynamics
When energy is converted from one form to another, some of the useful energy is always degraded to lower-quality, less useful energy.
Net Energy
Amount of usable energy remaining after the production cost is subtracted.Slide8Slide9
Developed vs. Developing UsageSlide10
Energy Resources
Where do we get our energy from?
World
Nonrenewable resources
~84%
Renewable resources
~16%
US (the largest user of energy)
Nonrenewable resources
~
90%
Renewable resources
~10%Slide11
US Energy Usage (2011)Slide12Slide13Slide14
US Energy Efficiency & Sustainability
Increase Energy Efficiency and Conservation
a. Requires many unpopular decisions
Decrease speed limits
ii. Eliminate government subsidies
Secure Future Fossil Fuel Energy Supplies
Oppositions:
environmental and economic
Develop Alternative Energy Sources
Who pays for this?
Gas taxes?
Meet the First Three Objectives Without Further Damage to the EnvironmentSlide15
Energy Cost ComparisonSlide16
Energy Resources
Basic Power Production
How do we make electricity???
Most power plants, no matter what type of fuel source utilized, create electricity in the same basic manner.Slide17
Basic Coal-Fired Power PlantSlide18
Non-Renewable Energy
Fossil Fuels
Most widely used source of energy in developed countries.
Derived from decomposition of buried plant and animal matter trapped under high temperature & pressure for millions of years.
Oil & Natural Gas
derived from animals
Coal
derived from plantsSlide19
Coal
World’s most abundant fuel
provides 60% of the world’s electricity supply
~50% in the US
also the dirtiest
C, S, Hg, As,
Cd
, etc.
Composed primarily of carbon
Includes small amounts of water and sulfurSlide20
Coal
Formed in several stages
Peat
- not a coal
Lignite
- low sulfur/low heat
Bituminous
- high sulfur/high heat
- most abundant form
Anthracite
- low sulfur/high heat
- most desirable/least abundantSlide21
Coal
Coal Reserves
USA
Russia
China
Australia
India
Coal Production
China
USA
India
Australia
IndonesiaSlide22
Coal
How do we extract coal?
Subsurface Mining
Used for coal reserves deep underground
Traditional “mines”
Very expensive and dangerous but less environmental damage
Surface Mining
used for coal nearer the surface
causes the most environmental damage
Area strip mining
flat terrain
Contour strip mining
Hilly or mountainous terrain
Open Pit Mining
deep pit digging
Mountain Top Mining
Destroys mountain ecosystemsSlide23Slide24
Coal
Surface Mining Control and Reclamation Act (1977)
Requires filling (reclaiming) of surface mines after mining
Reduces Acid Mine Drainage
Requires permits and inspections of active coal mining sites
Prohibits coal mining in sensitive areasSlide25
Coal
Coal Burning:
Releases large quantities of CO
2
into atmosphere
Greenhouse gas
Releases other pollutants into atmosphere
Mercury
Sulfur Oxides
Nitrous Oxides
Particulate Matter
Can cause acid precipitationSlide26
Coal
Power Generation
Can reduce air pollutants using
electrostatic precipitators
removes much of the particulate matter
scrubbers
removes SO
2
from emissions
fluidized bed boilers
mixes powdered coal and crushed limestone
reduces SO
2
, NO
x
, and particulate matter
produces ash as a byproductSlide27
Coal
Pros
High quality
Most abundant fossil fuel on the planet
Relatively inexpensive
Cons
Dirtiest fossil fuel
Releases CO, CO
2
, SO
2
, As, NO
x
, heavy metals
Pb
, Ni,
Cd
Mining can cause severe environmental degradation
Mining is very dangerous
Non-renewable resourceSlide28
Crude Oil/Petroleum
Primary Oil Recovery
Drilling a well and allowing gravity to push the oil into the pipe.
Secondary Oil Recovery
Injecting water into wells forcing remaining oil to surface of the well for extraction.
Primary + Secondary Recovery
Only extracts ~35% of oil from a reservoir
Tertiary Oil Recovery
Various process used to try and recover remaining heavy oil
Extremely expensive and uses a lot of energy.
1/3 barrel of oil used for every barrel recovered.Slide29Slide30
Crude Oil/Petroleum
Various Derivatives
Refining process separates various hydrocarbons based on boiling points.
Common
derivatives
Fractional distillationSlide31
Crude Oil/Petroleum
Petrochemicals
By-products of distillation process include components used in:
Plastics
Pesticides
Synthetic fibers
Paints
Medicines
FertilizersSlide32
Crude Oil/Petroleum
Oil Reserves & OPEC
Organization of Petroleum Exporting Countries
controls 78% of world’s proven oil reserves (and most of the unproved reserves)
Consists of 11 nations
Top
Proven
Oil Reserves
Venezuela*
Saudi Arabia
Canada**
Iran
IraqSlide33
Crude Oil/Petroleum
Top Oil Producing Countries
Saudi Arabia
Russia
USA
Iraq
ChinaSlide34
1989 Alaskan Oil Spill
Exxon Valdez hit a reef and spilled 260,000 barrels of crude oil into sound
Largest oil
tanker
spill in US
history-
BP
Oil SpillSlide35
Oil Pollution Act of 1990
Establishes liability for damages to natural resources during an oil spillSlide36
Keystone PipelineSlide37
Crude Oil/Petroleum
Pros
High quality energy
Energy is easily harnessed
Easily transported/stored
Cons
Non-renewable resource
Emissions from burning are extremely detrimental to environment and health
Prices are volatile
Production & Transport of oil can be dangerous
Deepwater HorizonSlide38
Natural Gas
What is it?
Primarily Methane (CH
4
)
50% - 90%
Can also include other heavy gaseous hydrocarbons
ethane (C
2
H
6
), propane (C
3
H
8
), butane (C
4
H
10), and hydrogen sulfide (H2S)
Conventional Natural Gas
Found above oil reservoirs
Unconventional Natural Gas
Found in coal beds, shale rock, dissolved in deep deposits of hot water
Methane hydrate
Small bubbles trapped in ice crystals deep under permafrost and beneath deep-ocean sediments.
Combined has 2x more energy than all oil, coal, and NG combinedSlide39
Natural Gas
LPG vs. LNG
Liquefied Petroleum Gas
Consists of liquefied propane and butane gases
Remaining gas (methane) is distributed into pressurized pipelines
Liquefied Natural Gas
Natural gas at very low temperatures
Typically used for shipping to other countriesSlide40
Natural Gas
Top Proven Natural Gas Reserves
Russia
Iran
Qatar
Top Natural Gas Producers
USA
Russia
Iran
Qatar
Canada
USA
Saudi ArabiaSlide41
Natural Gas
Pros
High Quality
Easily transported/stored
Less air pollution
Cons
Non-renewable resource
High emissions of SO
2
and H
2
S
Can be dangerous to handleSlide42
Synfuel
Synfuel
Synthesized fuel from coal and other naturally occurring sources
Used in place of oil or natural gas
Include:
Tar sands
Oil shales
Gas hydrates
Liquefied coal
Coal gas (right)Slide43
Fracking
Process of extracting Natural Gas and/or Oil from shale rock deep underground.
Involves injecting a mixture of water and chemicals underground to break up the rock
Allows for extraction of NG at that point.
Global fracking projects have dramatically increased in the last decade (especially in US)
Rising oil and NG prices
New technologies (better drilling equipment, 3D imaging)
Can be devastating to the surrounding environment
Water pollution in wells and aquifers
Contamination of soil
Geologic instabilitySlide44
Length of Supplies???
Difficult to determine and estimates vary
Depends on:
Locating more deposits
Future extraction technologies
Changes in global consumption rates
Experts indicate there may be shortages in 21
st
centurySlide45
Nuclear Energy
Very expensive and complicated technology.
Nuclear Fission Reactors
atoms of Uranium-235 or Plutonium-239 are split by neutrons which releases energy (heat)
entire reaction occurs in a moderator
water
controlled by using neutron absorbing control rods
boron carbide, silver, cadmium Slide46
Nuclear EnergySlide47
Nuclear EnergySlide48
Nuclear Fuel Cycle
Processes involved in producing the fuel used in nuclear reactors and in disposing of radioactive (nuclear) wastes Slide49
Nuclear Energy
450
commercial reactors in
30
countries producing
11%
of the world’s electricity.
60 new reactors currently under
construction in 15 countries
99
reactors in the US producing ~20% of our electricity.
Moratorium on new plants began in1979.
New ones have been approved and construction has begun however, including one in FL
France heavily relies on nuclear energy
~77% of France’s power generation
Heavily subsidized by the governmentSlide50
https://www.eia.gov/tools/faqs/faq.cfm?id=207&t=21
There are 61 commercially operating nuclear power plants with 99 nuclear reactors in 30 states in the United States. (The Indian Point Energy Center in New York has two nuclear reactors that the U.S. Energy Information Center counts as two separate nuclear plants.) Of these nuclear plants, 35 have two or more reactors. The Palo Verde power plant in Arizona is the largest nuclear plant, and it has three reactors with a combined net summer electricity generating capacity at 3,937 megawatts (MW). The R. E.
Ginna
Nuclear Power Plant in New York is the smallest nuclear plant, and it has one reactor with a net summer electricity generating capacity at 508 MW.
The newest nuclear reactor to enter service, Watts Bar Unit 2 with 1,150 MW net summer electricity generating capacity, began commercial operation in October 2016.
Four new nuclear reactors are actively under construction:
Vogtle
Units 3 and 4 in Georgia and Virgil C. Summer Units 2 and 3 in South Carolina.Slide51
Nuclear Energy
Meltdown
At high temperatures the metal encasing the uranium fuel can melt, releasing radiation
Probability of meltdown is low
Public perception is that nuclear power is not safe
Sites of major accidents:
Three Mile Island (PA)
Chernobyl (Ukraine)
Fukushima (Japan)Slide52
3 Mile Island
1979 - most serious reactor accident in US
50% meltdown of reactor core
Containment building kept radiation from escaping
No substantial environmental damage
No human casualties
Elevated public apprehension of nuclear energy
Led to cancellation and moratorium of many new plants in USSlide53
Chernobyl
1986 - worst accident in history
1 or 2 explosions destroyed the nuclear reactor
Large amounts of radiation escaped into atmosphere
Spread across large portions of Europe
Final death toll between 10,000 & 100,000Slide54Slide55
Nuclear Energy
Low-level radioactive waste
Radioactive solids, liquids, or gases that give off small amounts of ionizing radiation
High-level radioactive waste
Radioactive solids, liquids, or gases that give off large amounts of ionizing radiation
Mill Tailings
residue from extraction of uranium oreSlide56
Radiation in PerspectiveSlide57
Nuclear Energy
Long term storage of nuclear waste is an ongoing, global problem
spent nuclear rods require long-term storage in protected areas
concrete and water are most practical at blocking gamma rays
US currently stores wastes at “temporary” facilities
primarily onsite at power plantSlide58
Nuclear Energy
US currently stores wastes at “temporary” facilities
In nuclear plant facility (require high security)
Under water storage
Above ground concrete and steel casksSlide59
Nuclear Energy
Long term storage was planned for Yucca Mountain.
Project has been canceled
environmental concerns
$$$Slide60
Nuclear Energy
Licensed to operate for 40 years
Several have received 20-year extensions
Power plants cannot be abandoned when they are shut down
Three solutions
Storage
Entombment
Decommissioning (dismantling)Slide61
Nuclear Energy
Nuclear Fusion
Fuses two atoms of hydrogen isotopes
deuterium and tritium fuse at 100 million degrees
Haven’t been able to efficiently fuse atomsSlide62
Nuclear Energy
Pros
High quality
1g U
235
= 3.5 tons of coal
Very little air or water pollution.
Cons
Extremely expensive
High potential of deadly accidents
Very toxic waste products are produced
Non-renewable resource
NIMBYSlide63
Renewable Energy
What are they and where do they come from?
Sources of energy that are potentially sustainable because it can last indefinitely without reducing the original supply.Slide64
Solar Power
The sun is the ultimate source of energy for the earth.
Photovoltaic Cells
converts solar energy directly into electricity
extremely expensive and very inefficientSlide65
Solar Power
Active Solar Heating
absorbs solar energy and moves it into a building
solar water heater
Traditional Electricity Production
Involves concentrating
sunlight to one pointSlide66
Solar Power
Passive Solar Heating
captures sunlight directly within a structure and converts it to heat
greenhouse
South facing windows (in N. hemisphere)
Well insulated buildings
Attic vents
OverhangsSlide67Slide68
Solar Power
Pros
most abundant source of energy on earth
no emissions
renewable resource
Cons
low quality
expensive to build
inefficient to harnessSlide69
Biomass
Can be any organic material burned
wood, manure, plant fibers, dried algae
Heavily
used in developing nations
heats homes and cooks food
Also
used to create electricity
Sweden is leader
Can
be converted into biofuels
Utilizes bacteria or chemical processes
Creates gaseous and liquid fuels
Ethanol and Methanol
Biogas
60% CH
4
, 40% CO
2Slide70
Biomass
Pros
high quality
potentially renewable resource
as long as resources aren’t harvested faster than produced
Cons
Can be destructive to the land
Takes away food resources from people
open fires are extremely inefficient
70% of energy is lostSlide71
Wind
World’s fastest growing energy resource
Winds are harnessed by building turbine “farms” in suitable locations.
usually between 20-2000 turbines
must have consistent, strong winds
Best available sites to harness wind in US are the Great Plains states.
Largest users of wind power is Northern Europe and the US
Fastest growing use is in AsiaSlide72
WindSlide73
Wind
Pros
no air or water pollution
relatively cheap to build and operate
renewable energy source
Cons
low quality
unsightly (though less than a traditional power plant)
inconsistent power supply
may interfere with migratory bird routesSlide74
Hydropower
3 methods of electricity production:
Large-scale
High dam with a large reservoir
Small-scale
Low dam with no reservoir
Pumped-storage hydropower
Pumps excess water to reservoirs where electricity is neededSlide75
Hydropower
17 turbines – 2,000 MWSlide76
China’s 3 Gorges Dam
26 turbines – 18,200 MWSlide77
China’s 3 Gorges DamSlide78
Hydropower
Supplies
~16%
of the world’s electricity
Norway ~99%
New Zealand ~75%
US
~26%
China is largest producer of hydroelectricity
Can be high or low quality depending on the situation.
Pros
dams produce no air or water pollution
renewable resource
Cons
expensive to build
disrupts ecosystemsSlide79
HydropowerSlide80
Wave Energy
Converts wave energy into electricity
Pros
renewable energy source
many suitable locations located throughout the world
can be used to produce freshwater from seawater at the same time
Cons
low quality
expensive to build and maintainSlide81
Geothermal
Enormous potential energy source
1% of heat in upper 10km of earth’s crust = 500x earth’s fossil fuel sources
From Hydrothermal
Reservoirs
Created by volcanoes
Reservoirs used directly
for heat or to generate
electricitySlide82
Geothermal
From hot, dry rock
Geothermal heat pumps
Use difference in temperature between surface and subsurface
Great for heating buildings
Expensive installationSlide83
Geothermal
Currently used by 24 countries
mostly developing
Iceland is leader
Pros
high quality
relatively clean
Cons
very few concentrated and/or accessible sources of energy
can cause geologic instabilitySlide84
Tidal Energy
Converts tidal energy into
electricity- uses gravitational pull of the moon and sun as a
power source
Pros
renewable energy source
Cons
low quality
expensive to build and operate
very few suitable locations
only two plants currently in operation
La Rance, France and Bay of Fundy, Nova Scotia,
Canada
3 other large ones- South Korea, UK, ScotlandSlide85
Fuel Cell
Device that directly converts chemical energy into electricity
Requires H from a tank and O2 from the air.
Similar to a battery, but reactants are supplied from outside source.Slide86
Fuel Cells
Hydrogen and oxygen gases combine to produce electricity.
H is the most abundant element in the universe
Most H gas is currently produced from oil
H combines with O
2
in the air and produces water vapor
Pros
Very efficient
Only emission is water vapor.
High quality
Cons
Very expensive to build
Hydrogen is potentially dangerous to store and transportSlide87
Micropower
Proponents argue the future will be decentralized small-scale micropower systems.
Produce smaller amounts of electricity on site and disperse any excess to the traditional electrical grid.