APES Unit 6: Energy Resources and Consumption
Geothermal cons
- Accessibility is limited for reasonable cost - Release of gases during drilling and processing (hydrogen sulfide gas) - short-term depletion of heat - impact on groundwater supplies
Chernobyl, USSR
- Accident arose from a safety test - Power turned off during simulation - Extra power from turbine was supposed to keep reactor powered up enough to cool - When test completed, control rods didn't stop - Explosion occurred, releasing most radiation ever from an accident
Fukushima, Japan
- Accident caused by natural disaster - Earthquake and tsunami occurred in Pacific - Earthquake caused emergency shutdown of power - 3 nuclear reactors melted down at the same time - Accident was deemed preventable
Three Mile Island, Pennsylvania
- Accident started in non-nuclear portion - Water pump failed to allow water in - Reactor never cooled down - Fuel began to melt down partially - No explosion or long-term high radiation exposure
Biomass cons
- Air pollutants: CO2, CO, nitrogen oxides, particulates, VOCs - Typically burned indoors for heating or cooking, intensifying health effects of pollutants: CO poisoning, asthma, emphysema, bronchitis, lung cancer - Deforestation
Biofuel pros
- Combustion is carbon neutral - Renewable - Can be produced domestically
Biomass pros
- Easily accessible - Relatively inexpensive - Used for heating and cooking - Can be burned or decomposed for electricity
Active solar cons
- Expensive - Requires maintenance - Solar farms may negatively impact fragile desert ecosystems - Solar farms requires high solar intensity to maximize efficiency
Biodiesel
- Extracted and chemically modified oil from plants - Can be a direct substitute for diesel fuel
Ethanol
- Fuel source that can replace gas - Typically mixed with gasoline to create gasohol (90% gas, 10% ethanol) - E-85 and flex-fuel vehicles can run on a mixture of 85% ethanol, 15% gas
Active solar pros
- Generate electricity or heat - Large/small scale applications
PV cell pros
- Generation of electricity - Can reduce habitat destruction depending on installation - Large and small scale applications (remote village electricity) - Off the grid electricity
Passive solar cons
- Hard to change placement of windows - Energy cannot be collected or stored long term
Passive solar pros
- Inexpensive and low maintenance
Biofuel cons
- Net energy is low (more gasohol is needed to go the same distance) - Harvesting of crops=increased fossil fuels for harvesting, increased deforestation, reduction in soil fertility
Hydroelectric pros
- No air pollution - No waste - Relatively inexpensive electricity generation - Additional services provided by reservoir: recreation, fishing, extra water for irrigation
Geothermal pros
- No combustion - No CO2 emissions - Not dependent on variable weather factors like solar and wind
Wind pros
- Renewable - Clean, no emissions, no combustion - Allows for multiple land uses - Can be used offshore where there's more wind
Hydroelectric cons
- Upstream flooding of land for reservoir - Lower water and sediment levels downstream - Different water temperatures upstream and downstream - Disruption of flow rates and sediment in river - High maintenance cost for tidal - High construction costs for dams - Most viable sites are already used
PV cell cons
- Use is limited by availability of sunlight - Limited lifespan of PV cells - Expensive - Solar farms may negatively impact fragile desert ecosystems
Hydrogen fuel cells
- creates electricity chemically by combining hydrogen fuel with oxygen from the air - once used, battery must be recharged or discarded - chemical reactants can be added continuously - the fuel cell doesn't "go dead"
Nuclear cons
- long-lived hazardous waste/nuclear accidents - thermal pollution - Very high initial cost (billions) - Mining for construction & Uranium - Nonrenewable resource
Nuclear pros
- low/no CH4/CO2 emissions - high power output low cost (after initial construction) - no mining for fossil fuels - no primary/secondary air pollutants
Cons of fracking
- making well = groundwater contamination - release of VOCs - methane may get released - earthquakes from breaking the ground
Fracking steps
1. A well is made in the ground 3. Fracking fluid is pumped underground (water mixed with chemicals and sand) 4. Rig sends down fluid which breaks the ground 5. Gas flows out
Hydrogen fuel cell steps
1. Hydrogen fuel is added to the cell (liquid or gaseous) 2. Hydrogen molecules are split into protons and electrons a the anode 3. Protons move across the membrane, while electrons move through a separate circuit, creating an electric current 4. Oxygen molecules are combined with protons and electrons to form water vapor at the cathode
Geothermal steps
1. Water is pumped down an injection well 2. Stored heat from the Earth's interior turns the water into steam 3. Steam rises from the production well 4. Kinetic energy of the steam turns a turbine 5. The turbine turns a generator 6. The generator produces electricity
An industry uses natural gas for manufacturing and uses the waste heat to produce electricity. This is an example of which of the following processes? A) Cogeneration B) Electrolysis C) Gas hydration D) Gasification E) Reclamation
A) Cogeneration
Which of the following energy sources is not derived directly or indirectly from solar energy? A) Geothermal B) Photovoltaic C) Hydroelectric D) Biomass E) Wind
A) Geothermal
Negative environmental impacts associated with large-scale hydroelectric projects have been demonstrated in which of the following areas? A) James Bay, Quebec B) Three Mile Island, Pennsylvania C) Kissimmee River, Florida D) Mono Lake, California E) Aral Sea, former USSR
A) James Bay, Quebec
Which of the following is a way for the government to encourage efficient energy use? A) Requiring higher fuel economy standards for new cars B) Implementing government subsidies to keep gasoline prices low C) Raising the speed limit from 55 to 70 miles per hour D) Limiting the development of public transportation systems E) Removing all taxes from gasoline at the fuel pump
A) Requiring higher fuel economy standards for new cars
Most valuable coal
Anthracite because it has the lowest moisture and highest carbon concentration
A home uses ten 100-watt lightbulbs for five hours per day. Approximately how many kilowatt-hours of electrical energy are consumed in one year by using the lightbulbs? A) 365 B) 1,825 C) 5,000 D) 10,500 E) 365,000
B) 1,825
Which of the following is a true statement about passive solar heating? A) It is effective only during the summer months. B) It is based in part on the principle of the greenhouse effect. C) It is not used to heat commercial buildings. D) It is not efficient because it cannot produce high-quality energy. E) It produces more pollution than heating with an electric heat pump.
B) It is based in part on the principle of the greenhouse effect.
Anthracite
Best quality, high heating capacity, low sulfur content, deep underground, no moisture so very efficieny
Renewable energy resources
Biomass (wood, cow manure, corn stalks, biofuels), hydroelectric, solar, wind, waves, geothermal
Which of the following actions would reduce global greenhouse emissions? A) Increasing the use of automobiles B) Decreasing the number of nuclear power plants C) Replacing coal-burning power plants with wind farms D) Converting tropical forests to rice paddies E) Switching from hydroelectric power generation to power generation using natural gas as the primary fuel
C) Replacing coal-burning power plants with wind farms
All of the following substances are derived from petroleum EXCEPT A) asphalt B) DDT C) cellulose D) polystyrene E) nylon
C) cellulose
Environmentalists oppose the mining of antarctic mineral resources because A) territorial claims to Antarctica are unresolved B) the existence of valuable mineral deposits in the antarctic environment is unlikely C) the antarctic environment is fragile and extremely vulnerable to the disturbances that would accompany development D) currently known world reserves of important metals and oils are considered inexhaustible E) the demand for minerals is expected to decline as the world's nations become more industrialized
C) the antarctic environment is fragile and extremely vulnerable to the disturbances that would accompany development
Photovoltaic solar cells
Capture light energy from the sun and transform it directly into electrical energy; their use is limited by the availability of sunlight; when sunlight hits it, it releases electrons
Tar sands
Combinations of clay, sand, water, and bitumen
Sources for ethanol
Corn, sugarcane, sugar beets
An advantage of using natural gas, rather than oil, as a fuel is that natural gas is A) less of a contributor to global warming because it does not release CO2 when it burns B) less expensive because most reserves are in the United States C) more abundant because it is a by-product of photosynthesis D) cleaner because it burns more completely E) safer to store because it is a gas
D) cleaner because it burns more completely
One solution for reducing the amount of atmospheric carbon dioxide would be to A) increase oceanic temperatures to enhance carbon dioxide uptake B) increase the rate of removal of tropical rain forests C) decrease the total area of rice paddies D) decrease the use of fossil fuels E) decrease the production of chlorofluorocarbons
D) decrease the use of fossil fuels
______________ countries use the most energy globally
Developed
Hydroelectric energy
Electrical energy produced by the kinetic energy of flowing water
Tidal power
Electricity generated by the movement of sea water caused by the tides
Combustion chemical reaction
Fuel + O2 --> CO2 + H2O
Economic benefits of building large dams include which of the following? I. Storage of water for agriculture and domestic use II. Controlling floods upstream III. Production of renewable energy
I and III only
Flow of energy in hydroelectric dams
Kinetic energy of water from reservoir, spinning turbine, spinning generator, power lines
Least valuable coal
Lignite because it has a high moisture which decreases its efficiency and increases its impurities
3 types of coal
Lignite, bituminous, and anthracite
Biofuels
Liquid fuels made from plant matter that can be used as petroleum substitutes
Lignite
Low heat capacity, low sulfur, high moisture
Which region would be considered the world leader in petroleum resources? a) China b) Middle East c) Africa d) Australia
Middle East
Bituminous
Most commonly used, high heating capacity, high sulfur, some moisture but still efficient, produces the most sulfur in the atmosphere (sulfur emissions mix with H2O vapor which causes acid deposition)
Cleanest fossil fuel
Natural gas (mostly methane)
Nonrenewable energy resources
Nuclear, coal, oil, natural gas
Peat
Partially decomposed, organic material that can be burned for fuel
In which part of the power plant is waste generated?
Reactor
Top producers of natural gas
Russia, US, Iran
Top producers of crude oil
Saudi Arabia, Russia, Iran, Iraq, Venezuela
For a passive solar system, the window would have to be ________ facing if it were in the Northern hemisphere
South
Sources for biodiesel
Soybeans, oil palms
Passive solar energy
Systems that absorb heat directly from the sun without the use of mechanical and electrical equipment and cannot be collected or stored
Active solar energy
Systems that use solar energy to heat a liquid through mechanical and electric equipment to collect and store the energy captured from the sun
Top producers of coal
US, Russia, China, India, Australia
Wind turbines
Use the kinetic energy of moving air to spin a turbine, which converts the mechanical energy into electricity (direct generation of energy)
Cogeneration
When a fuel source is used to generate both useful heat and electricity (usually waste heat)
Radioactivity
When the nucleus of a radioactive isotope loses energy by emitting radiation
Examples of biomass
Wood, peat, charcoal, crop residue, MSW, and manure
Directions: Select the choice that best fits each statement. The following question(s) refer to the following energy sources. A) Biomass B) Wind C) Tidal energy D) Nuclear fission E) Sunlight The source whose use is a direct cause of deforestation
a) Biomass
Which of the following is most likely to occur in a forested region that has been recently clear-cut? A) The concentration of nitrates in streams running through the region will increase. B) The average depth of topsoil will increase. C) The water temperature in streams running through the region will decrease. D) Volume of runoff after rains will decrease. E) The frequency of landslides will decrease.
a) The concentration of nitrates in streams running through the region will increase.
Reflective surfaces heating liquid to create steam is an example of...
active solar energy
In 1997 the World Resources Institute estimated the world's proven oil reserves to be 1,000 billion barrels and the ultimately recoverable reserves to be 2,000 billion barrels. The table below shows the world consumption of oil from 1986 to 1997. What was the approximate percent increase in consumption from 1986 to 1997 ? A) 10% B) 20% C) 30% D) 50% E) 80%
b) 20%
Which of the following countries has the largest coal reserves? A) Saudi Arabia B) China C) India D) France E) Japan
b) China
At the 1997 rate of consumption, about how long will the estimated 2,000 billion barrels of oil last? A) 25 years B) 50 years C) 75 years D) 200 years E) 500 years
c) 75 years
In the majority of less developed countries, the major source of energy for domestic use is which of the following? A) Oil B) Coal C) Biomass D) Nuclear E) Geothermal
c) Biomass
Ethanol does not introduce additional _________ into the atmosphere via combustion
carbon (it releases modern carbon which is already in cycle)
Directions: Select the choice that best fits each statement. The following question(s) refer to the following energy sources. A) Biomass B) Wind C) Tidal energy D) Nuclear fission E) Sunlight The source that is not renewable
d) Nuclear fission
Directions: Select the choice that best fits each statement. The following question(s) refer to the following energy sources. A) Biomass B) Wind C) Tidal energy D) Nuclear fission E) Sunlight The source that produces long-lived hazardous wastes
d) Nuclear fission
Which statement best describes the approximate global distribution of coal supplies? A) Brazil and South Africa together contain 33% of proven reserves. B) The United States contains 40% of proven reserves. C) Australia, Japan, and France together contain 45% of proven reserves. D) The United States, the former Soviet Union, and China together contain 50% of proven reserves. E) Germany, Brazil, and India together contain 75% of proven reserves.
d) The United States, the former Soviet Union, and China together contain 50% of proven reserves.
Which is a benefit of the use of biomass as a fuel source? a) provides electricity in rural areas b) combustion of fuels creates very few pollutants c) increased deforestation d) relatively low-cost fuel source
d) relatively low-cost fuel source
A sustainable society would emphasize A) maintaining the current rates of energy flow and resource use B) converting the world's high-quality energy resources to low-quality heat C) recycling both matter and high-quality energy D) using energy efficiently and reusing and recycling matter E) quickly expanding nuclear power, because it is a renewable resource
d) using energy efficiently and reusing and recycling matter
Directions: Select the choice that best fits each statement. The following question(s) refer to the following energy sources. A) Biomass B) Wind C) Tidal energy D) Nuclear fission E) Sunlight The source that is converted directly into electrical energy by photovoltaic cells
e) Sunlight
Wood is commonly used as fuel in the forms of...
firewood and charcoal (developing countries)
Nuclear power is generated through...
fission, where atoms of Uranium-235 (stored in the fuel rods) are split into smaller parts after being struck by neutrons
The most widely used sources of energy globally are...
fossil fuels
Natural gas is obtained through...
fracking
Ethanol can be use as a substitute for...
gasoline
Hydrologic fracking can cause...
groundwater contamination and the release of volatile organic compounds
Nuclear fission releases a large amount of heat, which...
is used to generate steam, which powers a turbine and generates electricity
Uranium-235 remains radioactive for a long time, which...
leads to problems associated with disposal of nuclear waste
Petroleum is the same as...
oil
Sun that heats up a house through window is an example of...
passive solar energy
Oil and natural gas form at the...
same time
Crude oil can be recovered from...
tar sands
As developing countries become more developed...
their reliance on fossil fuels for energy increases
Geothermal energy is obtained by...
using the heat stored in the Earth's interior to heat up water, which is brought back to the surface as steam; the steam is used to drive an electric generator
The only waste product from HFCs is...
water vapor
