Geology Exam #3 Flashcards
What is a source of energy you are familiar with in your daily life?
Solar, Geothermal, (get more from slides)
Society is ______ on a continuous flow of energy.
dependent
Why has the demand for energy consumption increased?
new technology and larger population
How much more is personal consumption now compared to early humans?
100X
Collectively, how much more energy does society use than in 1865?
70X
True or False: No energy source is 100% clean?
True, but some sources are cleaner than others.
What human activities require energy?
Heat/cooling buildings, illuminating buildings/streets, gas up or charge cars, plant/harvest/ship food.
How was energy sourced a century ago vs now?
A century ago, energy was sourced from wood, peat, and dung (biomass). Now, it is sourced by fossil fuels and nuclear fuels.
What are the factors that energy sources can be evaluated on?
concentration, availability, versatility, cost to obtain and process, safety/hazard potential, and environmental damage.
True or False: global energy consumption has increased dramatically since 1970 as well as differs between developing and developed countries.
True
Who is the leading consumer and producer of primary energy in the world? How much do they consume/produce?
The United States consumes about 25% more energy than it produces. It is the leading CS of primary energy in the world. Additionally, much of the US energy comes from fossil fuels.
What three aspects of consumption take up the most energy from the US’s total production?
Electricity, rejected energy (waste), and Transportation.
What is a large portion of the energy sector devoted to supplying for consumers?
Electricity to run electrical appliances, lighting, heating, etc.
How are most commercial power plants described?
By the type of primary energy used to operate turbine-driven generators.
Electricity is generated by the flow of what in metal wire?
electrons
Electricity can be generated from almost any energy source through the use of a turbine. What is the process?
- Energy source turns a turbine
- Turbine turns a generator.
- magnet spins around copper wires causing electrons to move from atom to atom in a wire.
This creates electricity in homes!
Where does power plant environmental impact occur?
Impacts can occur far away from those who use the energy, but power plants are less efficient with distance.
True or False: Utilities often have less generating capacity than actually needed most of the time.
False. There is actually a surplus of capacity that provides a reserve of energy ready to meet any peak demand.
True or False: Hard technologies are small-scale plants that are complex, expensive, and centralized requiring energy transport.
False. Hard tech is large scale. Everything else is true.
True or False: Soft technologies are small-scale generation and applications that are evenly distributed, flexible, and usually more efficient.
True
Energy efficiency is the amount of _____ energy in a source that is converted into useful work (not wasted).
available
Energy efficiency ranges from 0-100% availability; there is room for improvement in most cases. List different energy efficiency examples.
Natural gas stove ~40%
Electric induction stove ~84%
Natural gas electricity ~60%
Incandescent bulbs ~2-3%
Fluorescent bulbs ~10%
Light-emitting diodes (LED) ~100%
What is Cogeneration?
The production of two useful forms of energy from the same fuel. This is more effective on a small-scale.
Ex: Capturing waste heat from electricity generation and using it to make hot water for another process.
How can homes be built with energy efficiency at point-of-use?
Super-insulated buildings, south facing windows, insulating glass, and using high “thermal mass” materials such as concrete floors.
True or False: Net zero energy buildings produce as much or more energy than they consume.
True
What are things humans can do to reduce energy use?
Reduce commute lengths, use public transportation/bike, turn off lights when not in use, and reduce temperature on the thermostat at night.
Many energy resources are not available when we want them. Provide some examples and give a solution.
Too little: Solar and wind energy can be intermittent.
Too much: Large coal and nuclear plants are most efficient with constant energy output.
Solution: storage of unused energy
What are some examples of energy storage?
Electrochemical Energy Storage (batteries)
Pumped Hydroelectric Storage
Compressed Air Energy Storage
Thermal Energy Storage
True or False: Fossil fuels are buried organic deposits formed from plants and microscopic organisms that are stored in solar energy.
True. They are NOT the remains of dinosours.
Fossil fuels are a major component of global energy resources. How are fossil fuels made?
Associated with sedimentary rocks, fossil fuels were converted to crude oil, coal, and natural gas by exposure to heat and pressure in the earth’s crust over millions of years.
What are carbon-based energy sources three primary forms?
Solid (coal, lignite), Liquid (oil), and Gas (methane)/gas hydrate.
All three represent stored solar energy that can be accessed through oxidation of a carbon-based molecule (burning or combustion).
Fossil Energy is primarily what?
hydrocarbons (CH). These are formed from the preservation and biogeochemical alteration of organic material after burial such as plant matter (coal) and plankton (petroleum & gas).
How does coal form?
Plants grow and die in dense accumulations in low-lying, coastal areas. The sediment deposition shifts due to changes in sea-level and the organic matter get buried where it is compacted into peat.
Coal products are divided into four separate categories based on carbon content and material. Water and gas (volatiles) are removed with each step.
Peat: 1-25%
Lignite: ~35%
Bituminous: 45-85%
Anthracite: >85%
What does accessing coal deposits depend on?
the method depends on depth of seam in Earth
True or False: coal exists as layered deposits and is not always exposed at the surface.
true
What is an overused method when accessing coal deposits?
strip mining
Where are active Tenessee coal fields?
Claiborne, Campbell, and Anderson counties
True or False: fossil fuels (and coal) may continue to be part of the energy mix for the next 30+ years, despite renewables increasing rapidly.
True
Electricity generation in _____ nations will require much more energy “on the grid” leading to extended use of fossil fuels like coal.
developing
How much longer could coal last based on the “bubble patter” of non-renewable resources.
400-600 years
Coal is pulverized and combusted in traditional power plants to heat water into what?
steam
Products of _____ rise with waste heat out of the “smokestack”
combustion
Sometimes a flux (limestone chips) is added to help capture what?
toxins
What reduces toxic emissions by forcing condensation in the tower (Clean Air Act)?
Scrubbers
What impacts are associated with coal?
harmful environmental pollutants from mining to storage to usage
Burning coal releases what into the atmosphere leading to acid rain (pH < 5.6)/snow and acid deposition.
Sulfur and nitrogen
Coal also impacts the hydrosphere. Abandoned mines are sources of ____ mine drainage (AMD), caused by water mixing with pyrite and other minerals exposed in the coal.
acid
Some examples of after effects of coal impact are…
coal ash & sludge
abundant toxic metals: arsenic, mercury, chromium, and cadmium
Half is stored in coal power plant waste centers and can be reused while the other half is stored in retention ponds.
Where is the biggest coal plant in TN?
Kingston
In 2008, what retention pond failed caused 4.1 million cubic meters of sludge to flood into local TN rivers?
The Kingston Retention Pond
How was the Kingston plant spill cleaned up?
berms, vacuum trucks were used to pick up concentrated pollutants that caused life-threatening deformities in local organisms.
Why were workers involved in the clean up of the Kingston plant spill affected?
Having to interact with the waste for years caused many of them to form major health issues.
Why does it matter where the toxic sludge was placed from the Kingston plant spill?
This toxic waste was placed in a predominantly low-income African American community in Alabama. Though the waste is considered hazardous in TN, it is not considered as such in AL. Thus, exposing many of these locals to toxic substances.
Globally, who contributes the most CO2 emissions? What is most of it from? What is the current trend?
China & the US; burning coal; continuous increase
What are some raw materials for Oil & Gas Formation?
Plankton, algae, spores, and pollen when in contact with heat & extreme pressure create kerogen: a brown, waxy substance.