Post on 24-Feb-2016
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Energy
Energy Consumption Wood served as the predominant energy source until the Industrial Revolution, when coal usage surpassed wood.During the 20th century, petroleum
surpassed coal.
Most energy in the US is used by industries, followed by transportation, residential, and commercial.
In the 1950’s, energy consumption in the US
outpaced domestic production, leading to oil
imports. By 1998, net imports of oil surpassed the domestic
supply of oil.
Global Energy UseIn the US, most of the
energy comes from nonrenewable energy
sources such as coal, oil, natural gas, and
uranium.
Renewable energy resources include
biomass, geothermal, hydropower, solar energy, and wind
energy.
CoalCoal is a fossil fuel produced by the burial and compaction of ancient organic matter under high temperature and pressure.
Sulfur is produced from the decomposition of hydrogen sulfide (H2S) by anaerobic
bacteria trapped in the coal.
CoalCoal is obtained through surface or
underground mining
CoalCoal supplies 25% of the world ’s energy.
In the USA, 87% of the coal is used for power plants to produce electricity.
Coal is burned to turn water into steam which turns giant turbines inside electrical
generators.
Advantages of Coal•Abundant world and US reserves that will last hundreds of years•Unidentified reserves that are estimated to last thousands of years•Relatively high net-energy yield•US government subsidies keep prices low•Stable, non-explosive, not harmful if spilled•Can be turned on and off easily to control energy output
Disadvantages of Coal•Mining for coal is destructive on
the environment, decrease biodiversity, and increase pollution runoff•Burning coal releases mercury and sulfur into the air.•35% of all CO2 emitted into the air is due to the burning of coal•30% of all nitrogen oxide related pollution•Coal cannot be used effectively for transportation needs
Clean CoalClean coal technology refers to the processes that reduce the negative environmental effects of burning
coal such as washing coal to remove minerals and impurities and capturing sulfur dioxide and
carbon dioxide gases.
PeatPeat forms from the compaction of
partially decayed plant material. (looks like soil)
-Peat is the 1st step in coal formation
PeatPeat is mainly used in Europe.
(Ireland, Scotland, Finland, Russia)
Peat is harvested from bogs.
Peat AdvantagesPeat is abundant in NW Europe
and cheapPeat burning gives off less air
pollutants like sulfur oxide than coal and oil
Peat DisadvantagesPeat harvesting can completely
destroy bogs which are complex and important ecosystems
Oil is another fossil fuel
produced by the decomposition of
deeply buried organic material (plants) under
high temperatures and
pressures for millions of years.
Oil
OilOil is released by drilling a well and
puncturing thelimestone layer.
Since the oil is already under great pressure, the oil flows naturally from the well.
OilOnce the crude oil is collected it is
sent to a refinery where it is “cracked” or separated into
different types of oil by boiling.
Advantages of Oil•Inexpensive but prices are increases•Easily transported through established pipelines•High net-energy yield•Ample supply for the immediate future•Versatile – used to make many products (paints, plastics, medicines)
Disadvantages of Oil•World reserves are limited and declining•Produces pollution (SO2, Nox, and CO2)•Causes land disturbances during drilling process•History of oil spills both on land and in ocean from platforms and tankers•Disruption to wildlife habitats•Supplies are politically volatile
Oil Spills on Land
800,000 gallons into Kalamazoo River in
Michigan from Canadian pipeline (2010)
Oil Spills on Land420,000 gallons of oil spilled into
Mississippi Riverwhen two barges collided. (2008)
Oil Spills on Land30,000 liters from
pipeline into the Red Deer River in Alberta
Canada (2008)
4.5 millionliters of oil spilled into the Peace River in Canada
(2011)
Oil Spills on WaterDeepwater Horizon Oil Spill into the Gulf of
Mexico (April, 2010)Released 4.9 million barrels of oil
Oil Spills on Water•1967 – United Kingdom – Tanker accident - 919,000 gallons•1970’s – 6 ocean oil spills•1983 – South Africa – Tanker Fire – 1.8 million barrels•1989 – Alaska, USA – Exxon Valdez – Tanker accident – 240,000 barrels•1990 – California, USA – Tanker Leak – 300,000 gallons into reserve•1991 – Kuwait – Iraq invasion - 240 million gallons•1990’s – 25 other ocean oil spills•2000 –2005 – 24 ocean oil spills•2005 – 9 incidents – Hurricane Katrina•2006 – 2010 – 15 ocean oil spills•2010 – 13 incidents – Deepwater Horizon•2011 – 10 ocean oil spills
Energy CrisisThe price of energy is driven by supply and demand. In some cases, and energy crisis is
brought on by the failure of world markets to adjust prices in response to shortages.
OPECOrganization of Petroleum Exporting
Countries. Association of nations with large oil reserves
that control oil supply
OPECWhen OPEC reduces
the output quotas of its member countries, the price of oil increases as the supply decreases.
When OPEC boosts oil production to
increase supplies, the price of oil
decreases.
Nuclear EnergyNuclear fission occurs when an atom splits into two or more smaller nuclei along with byproducts of neutrons, photons, gamma
rays, beta rays, and alpha particles.
Nuclear EnergyNuclear fission is an exothermic reaction
producing heat. Under controlled conditions, the heat is used to produce
steam that turns a turbine to generate electricity at nuclear power plants.
Nuclear Energy•The amount of potential energy contained in nuclear energy is 10 million times more than that of fossil fuels.•The downside is that the nuclear wastes remain highly reactive for thousands of years.
Nuclear FuelsThe most common nuclear fuels
are Uranium and Plutonium
Little Boy - Hiroshima
Uranium Nuclear Weapons
Plutonium Nuclear Weapons
Fat Man - Nagasaki
Nuclear FuelsNuclear power plant use began in the USA
duringthe 1960’s and increased until the late
1980’s.Decline in the building of new plants was
due to cost overruns, high operating costs, safety issues, and nuclear wastes.
Nuclear Power Plants1) The reaction takes place in the
reactor core with fuel rods2) Control rods slow down the
reaction.3) Water coolant removes the heat
and produces steam to generate electricity.
Coolant WaterLight water reactors use lake or river
water as coolants. The radioactive water does not come in contact with
the water used as condenser that comes from a nearby river or lake.
Advantages of Nuclear Power•No air pollutants
•Disruption of land is low to moderate•Water pollution is low
Disadvantages of NuclearPower•Nuclear wastes take millions of
years to degrade•Storage problem – safety and terrorists•Safety issues
Three Mile IslandThree mile island was a partial nuclear
meltdown in Pennsylvania in 1979 when a relief valve was stuck open, allowing the
nuclear reactant coolant to escape.
ChernobylIn 1986, the Chernobyl nuclear power
plant in the former Soviet Union experienced an explosion and fire that released large amounts of radioactive
particles into the atmosphere.
ChernobylThere were 28 deaths due to acute
radiation syndrome, mostly among the firemen, 15 deaths from thyroid cancer already, and a projected total of 4,000
future deaths from cancer.
Adults Teenagers Children
Abandoned city of Pripyat with Chernobyl in the distance
JapanThe Fukushima Daiichi plant, 240 km (150 miles) northeast of Tokyo, was wrecked by a huge earthquake and a towering tsunami
which knocked out its cooling systems, triggering meltdowns, radiation leaks and
mass evacuations. (2011)
Natural GasNatural gas, or methane, is produced by the
decomposition of buried organic matter under high pressure and temperatures.
Natural GasNatural gas is usually present
immediately above the oil.
Advantages of Natural Gas•Pipelines in place
•Relative inexpensive, but prices are increasing•High net energy yield•Produces less pollution than other fossil fuels
Disadvantages of Natural Gas
•Pollution is released during processing•Leakage of methane has a greater impact on global warming than CO2
•Extraction releases contaminated wastewater and saltwater
Hydroelectric PowerHydroelectric power uses dams to trap
water which is used to turn turbines that generate electricity.
Hydroelectric Power Pros•Dams control f looding
•Low operating and maintenance costs•No waste product•Long life span•High energy yield•Creates areas for water recreation
Hydroelectric Power Cons•Create large flooded areas,
displacing people•Expensive to build•Destroys wildlife habitats•Interrupt fish migration•Sediment builds up•Subject to earthquakes
Colorado RiverThe Hoover Dam, built
in the 1930’s, has reduced the amount of water reaching Mexico by way of the Colorado
River to 1/10 that it used to be before the
dam.
Colorado River in Mexico
Burst Dam – Johnstown, P.A.
Alternative EnergyAlternative energy sources include:
solar, wind,biomass, geothermal, and wave energy.
Solar EnergySolar energy consists of collecting and
harnessing radiant energy from the sun to provide heat and/or electricity. Solar panels are used to generate electricity.
Solar EnergySolar energy Advantages:•Supply of solar energy is limitless•Little environmental impact•Low pollution•Can store energy during day for use at night
Solar energy Disadvantages:•Inefficient where sunlight is limited•Maintenance costs are high•Low efficiency
Hydrogen FuelCells
Hydrogen fuel cells use hydrogen fuel and oxygen from the air to
produce electricity
Hydrogen Fuel
CellsFuel Cells Advantages:•Waste product is pure water•Does not destroy wildlife habitat
Fuel Cell Disadvantages:•Takes energy to produce hydrogen•Hydrogen gas is very explosive
Biomass EnergyBiomass is any carbon-based, biologically derived fuel source grown specifically for
bio-fuel.
•Corn•Sugar cane•Hemp
Biomass EnergyBiomass Advantages:•Renewable energy sources (sustainable)Biomass Disadvantages:•Requires land, water , fertilizer, and herbicides•Air pollution•Expensive to transport due to weight•Not efficient
WindEnergyWind turns giant turbine blades that
then power generators.All of USA’s demand could be met by
wind in the Dakotas and Texas
WindEnergyWind Advantages:
•Quickly built•Low maintenance•High energy yield•No physical pollution•Multiple use of landWind Disadvantages:
•Few suitable places
•Visual and noise pollution•Interferes with bird migration
Wave and Tidal Energy
• Natural movement of waves and tides turn turbines that generate electricity.
• France and Bay of Fundy contain the only operating plants so far.
http://www.youtube.com/watch?feature=player_embedded&v=EnDJ6_XpGfo
Wave and Tidal EnergyWave and Tidal Advantages:
•No pollution•Minimal environmental impact
Wave and Tidal Disadvantages:•Construction is expensive•Few suitable sites•Equipment can be damaged by storms and corrosion
Geothermal Energy•Heat contained in underground rocks from magma produce pockets of underground steam and hot water.•Geothermal energy uses this steam to generate electricity.•Currently used in Hawaii, Iceland, Japan, Mexico, New Zealand, Russia, and California.