Unit 6 APES College Board

Which of the following is the approximate projected rate of change in renewable energy consumption from 2010-2040?

A. 4.33 quadrillin BTUs per year

B. 2.33 quadrillion BTUs per year

C. 2.00 quadrillion BTUs per year

D. 0.733 quadrillion BTUs per year

B. (2010 BTU - 2040 BTU) / (30 years = 2.33

(Diagram)

Which of the following best describes the total cosumption of all fossil fuels in 2040

compared to the consumption of nuclear energy in 2040?

A. Consumption o fossil fuels will be approximately 13 times greater than consumption of nuclear energy

B. Consumption of fossil fuels will be approximately 9 times greater than consumption of nuclear energy

C. Consumption of fossil fuels will be approximately 5 time greater than consumption of nuclear energy

D. Consumption of fossil fuels will be approximately 4 times greater than consumption of nuclear energy

A. (2040 BTU of liquid + 2040 BTU of natural gas + 2040 BTU of

coal) / (2040 BTU of nuclear) = 12.86

Which of the following statements best describes a difference between nonrenewable and renewable energy sources?

A. Nonrenewable energy sorces release carbon dioxide when used, whereas renewable energy sources do not release carbon dioxide

B. Renewable energy sources are often obtained a long distance away from the customer, whereas nonrenewable energy sources are obtained locally

C. Renewable energy sources can be replaced naturally at current consumption rates, whereas nonrenewable energy sources cannot be replaced easily

D. Renewable energy sources produce energy that can be recycled after use, whereas the energy from nonrenewable energy sources cannot be recycled

C. renewable energy sources can be replaced naturally at current consumption rates, whereas nonrenewable energy sources cannot be replaced easily

After the Industrial Revolution, the use of fossil fuels increased significantly.

Which of the following statements best explains why there is continued widespread use of nonrenewable fossil fuels in energy production in the United States?

Responses

A. Established technology and transportation infrastructure for fossil fuels allows these resources to be converted into energy to meet consumer demand.

B. Fossil fuels are significantly cheaper than renewable resources, so they do not require government subsidies, which ultimately saves the government money.

C. The environmental effects of fossil fuels are easy to mitigate, while the environmental effects of renewable resources are difficult to understand and reverse.

D. Fossil fuels will always be present and are plentiful in quantity, so there is little pressure to find a replacement for them as an energy source.

A. Systems are already in place to transport and deliver fossil fuels. Additionally, coal, oil, and natural gas can be burned when energy is needed, versus wind and solar energy, the generation of which depends on environmental conditions.

(Diagram) (WIND Mini: 170, Avg: 197, Max: 82)

(HYDRO min:69, avg: 84, max: 107)

Based on the data above, approximately how much greater is the average cost of electricity produced in the US from offshore wind than from hydroelectric power?

A. 0.42 times greater

B. 0.88 times greater

C. 2.3 times greater

D. 3.9 times greater

C. (wind farm avg) / (Hydro avg) = 2.3

Natural gas, a nonrenewable fossil fuel, is often seen as an alternative fuel in the worldwide transition to a renewable energy future.

Which of the following statements best explains why natural gas is often used as a fuel when countries are transitioning from nonrenewable to renewable energy sources?

Responses

A. Natural gas burns more efficiently and cleanly than other sources of carbon-based fossil fuels, thus contributing to a reduction in atmospheric carbon dioxide.

B. The infrastructure for storing and transporting natural gas can be used in the future in conjunction with hydrogen fuel technologies.

C. Natural gas can be used in industrial applications only, but it has great potential to replace coal as a fuel source.

D. The process of extracting natural gas, known as hydraulic fracturing, requires very little water or energy.

A. Natural gas has fewer impurities than do coal and oil, so upon combustion it emits very little sulfur dioxide or particulates and much less carbon dioxide into the atmosphere.

Which of the following is an example of the process of cogeneration?

A. Using timber waste products as biofuel

B. Using wastewater from electricity production for heating homes

C. Using the corn crops for ethanol fuel production

D. Using the reservoir behind a hydroelectric dam for recreation

B. Cogeneration is the use of a power plant to generate electricity and useful heat at the same time. In combined heat and power plants, wastewater is recovered and the thermal energy is used for heating.

Which of the following best describes why people in less developed countries use wood as a primary energy source?

Responses

A. The infrastructure required to transport wood is well established.

B. Wood produces fewer carbon emissions than other energy sources, such as geothermal or natural gas.

C. Wood can be converted to peat and cheaply burned for fuel.

D. Wood, in the form of firewood and charcoal, is often readily available.

D. Wood is easy to access in less developed countries. Wood is commonly used as fuel in the forms of firewood and charcoal.

(Diagram) (coal deposits on Eastern US)

Which of the following geologic profiles would most likely be found at the circled region in the figure?

Responses

A. metamorphic rock to igneous rock

B. peat to peat to sedimentay rock

C. clay to sandstone to silt to igneous

D. sediment to igneous to magma to igneous

B. This diagram shows the peat layer within sedimentary rock, which is composed of the coal deposits found in this region.

(Diagram with energy idependent and dependent countries)

Which of the following statements about the global distribution and use of fossil fuels is best supported by the data on the map?

Responses

A. Saudi Arabia and Australia produce large volumes of fossil fuels with relatively low energy demand.

B. United States produces more fossil fuels than it consumes.

C. Japan has the greatest energy independence because there are abundant reserves of fossil fuels present in the country.

D. Russia and Indonesia are reliant on the export of other nations for their fossil fuels.

A. Saudi Arabia and Australia have the largest energy surplus based on the data on the map. These countries produce significantly more fossil fuels than they use.

(Diagram with rock cycle)

If a country possesses large oil and gas reserves within its borders, which of the labeled rock types must be present in the underlying geology of the country?

A. Magna

B. Igneous

C. Sendimentary

D. Metamorphic

C. The vast majority of oil and gas reserves around the world are found in sedimentary rocks. All the source rocks for oil and gas are sedimentary.

Which of the following describes a step in the generation of electricity using fossil fuels that can most directly lead to an environmental problem?

Responses

A. Fossil fuel is burned to boil water.

B. Water is converted to steam.

C. Steam turns a turbine.

D. Turbines power a generator.

A. One of the products of burning fossil fuel is carbon dioxide, a greenhouse gas that can cause increased global warming when released into the atmosphere. Burning fossil fuels can release other pollutants (depending on the type of fuel) such as particulates and mercury.

Which of the following best describes an environmental problem that is often linked to the process of fracking?

Responses

A. Fracking operations require large tracts of land, which degrades habitat and harms wildlife.

B. Fracking can increase stream flow and water volume, disrupting fish migration pathways.

C. Wastewater from fracking operations is injected into porous rock formations, which can induce seismic activity.

D. Excessive nutrients, such as nitrogen and phosphorus, run off the land near fracking sites, which can lead to large algal blooms in nearby waterways.

C. The disposal of wastewater from fracking operations is linked to an increase in earthquakes. Fracking extracts large amounts of water from underground oil-rich rocks, then pumps the water back underground, which sometimes triggers earthquakes.

Which of the following best describes a potential negative environmental effect of fossil fuel extraction?

Responses

A. Fossil fuel extraction requires new infrastructure and has a high start-up cost.

B. Birds are injured or killed when they fly around extraction sites.

C. Thermal energy produced during the extraction process is released into nearby streams and lakes.

D. Air pollutants, such as methane and particulate matter, are emitted into the atmosphere.

D. The extraction of fossil fuels creates air pollutants from leaking active oil and gas wells as well as from fossil fuel transportation and processing. Toxic air pollutants, such as benzene, formaldehyde, and very small particulate matter, are all negative effects of fossil fuel extraction.

(Diagram of pressurized water nuclear reactor)

In the diagram above, which letter correctly identifies the step where kinetic energy is converted to mechanical energy?

A. Control rod area

B. Going to steam line

C. wheel near generator

D. U-shaped part

C. The kinetic energy of the water molecules causes the turbine blades to spin, converting kinetic energy to mechanical energy.

Which of the following correctly depicts the nuclear chain reaction that occurs in a nuclear

power plant? (Diagrams)

A. neutron to atom to 2 electrons to 2 atoms to 4 electrons

B. neutron to atom to 2 neutrons to 2 atoms to 4 neutron

C. neutron to atom to electron/neutron/proton to 2 atoms to 4 electrons

D. neutron to atom to 2 neutrons to 2 atoms to 2 electrons 2 neutrons

B. Chain reactions occur because of an interaction between neutrons and isotopes, such as Uranium-235, which then releases additional neutrons. In this image, electrons are released from the reaction, which would not interact with other isotopes and continue the chain reaction.

(Diagram Nuclear power plant)

At which of the following locations in the nuclear power plant would an accident most likely result in the release of fission products?

A. tank

B. between transformer and turbine

C. In containment building

D. between pump and turbine

C. The reactor vessel holds the uranium fuel that is undergoing fission reactions that result in heat production.

Solar energy systems have been increasing the percentage of energy they contributed to the global energy supply. One of the fastest growing types of solar energy systems uses photovoltaic (PV) cells. (Diagram w/ energy usage in July with bell shape curve)

Which of the following best describes how a homeowner using an off-the-grid PV solar system, in the same country as seen in the graph above, can power a home between 9:00 PM and 6:00 AM?

Responses

A. Switching to the electrical grid to obtain power

B. Relying on sources like wind or hydroelectricity in times of darkness

C. Using excess energy from a sunny day stored in batteries for power

D. Burning wood to create heat and light for the home.

C. Batteries are the standard way to store energy for times when PV is not generating.

Solar energy systems have been increasing the percentage of energy they contributed to the global energy supply. One of the fastest growing types of solar energy systems uses photovoltaic (PV) cells. (Diagram w/ energy usage in July with bell shape curve)

Which of the following time periods has the highest energy output?

Responses

A. 10 am-12 pm

B. 12 pm-2 pm

C. 2 pm-4 pm

D. 4 pm-6 pm

B. For the entire time period between the hours of 12 pm and 2 pm, the energy output per hour is above 20Gw. The energy output is highest during this period of time

Solar energy systems have been increasing the percentage of energy they contributed to the global energy supply. One of the fastest growing types of solar energy systems uses photovoltaic (PV) cells. (Diagram w/ energy usage in July with bell shape curve)

Which of the following graphs best predicts the solar energy output in the country in the Northern Hemisphere in December?

A. Sharper peak

B. Smaller curve w/ less usage

C. larger curve with more usage

D. Dome shaped

B: In December, the length of daylight will be shorter and maximum solar radiation will decrease, resulting in the pattern of decreased solar energy output as seen in the graph.

Wind energy is increasingly relied upon to help meet global energy needs. Wind energy can be used to generate electricity using wind turbines.

Which of the following best describes electricity generation using wind turbines?

Responses

A. Newer wind turbines can generate consistent electricity even when there is no wind.

B. Wind turbines can be constructed on either vertical or horizontal axes.

C. Wind turbines are rarely used offshore because they tend to float in rough seas.

D. Wind turbines can be used by individual homeowners but have limited effectiveness when connected to the electrical grid.

B: Axes of wind turbines can be either vertical or horizontal; there are benefits (and drawbacks) to each type. Turbines aligned on a horizontal axis are the primary type seen and are common in large-scale operations. Turbines with vertical axis blades are perpendicular to the ground and work well in more extreme conditions.

Wind energy is increasingly relied upon to help meet global energy needs. Wind energy can be used to generate electricity using wind turbines.

Which of the following correctly identifies the sequence of energy conversions that occur in a wind turbine?

Responses

A. Mechanical energy → kinetic energy → electrical energy

B. Potential energy → mechanical energy → kinetic energy

C. Kinetic energy → mechanical energy → electrical energy

D. Potential energy → electrical energy → mechanical energy

C: The kinetic energy of the wind spins the blades. The main shaft of the rotor spins (mechanical energy) a generator to generate electricity (electrical energy).

Wind energy is increasingly relied upon to help meet global energy needs. Wind energy can be used to generate electricity using wind turbines.

Which of the following are often used for energy storage of wind power?

Responses

A. Converters

B. Generators

C. Batteries

D. Rotor blades

C: Batteries are a common way to store electricity generated by wind turbines. When the wind blows, batteries can be charged, and then, when the wind slows down or stops, the batteries can supplement power requirements.

Refrigerator A uses 500 watts per hour when the motor is operating. The motor needs to run an average of 12 hours per day, every day, to stay at a constant, cold temperature. This model of refrigerator lasts an average of 20 years before it needs to be replaced and costs $1,000.

Each kWh of electricity costs $0.12.

How many kilowatt hours (kWh) per year does refrigerator A use?

Responses

A. 6kWh

B. 182kWh

C. 2,190kWh

D. 2,190,000 kWH

C: The usage is converted from W to KW. Then the value is multiplied by the number of hours the motor runs per day and then by the number of days in a year. 500Wx (1kW/1,000W)

(2hours/1day) (365days/lyear) =2,190kWh

Refrigerator A uses 500 watts per hour when the motor is operating. The motor needs to run an average of 12 hours per day, every day, to stay at a constant, cold temperature. This model of refrigerator lasts an average of 20 years before it needs to be replaced and costs $1,000.

Each kWh of electricity costs $0.12.

The homeowner is considering purchasing a new model of refrigerator, Refrigerator B. This model uses 50 percent less energy per year. Which of the following would be the estimated cost savings for the homeowner in a year if she replaces Refrigerator A with Refrigerator B?

Responses

A. $30.00

B. $131.40

C. $262.80

D. $500.00

B: This value is obtained by taking the annual energy usage for refrigerator A (as determined in the previous question) multiplying it by the cost per KWH and then dividing it by 2 to account for the statement that refrigerator B is 50% more efficient. The cost should be half as much for refrigerator B.

(2,190kWHx$0.12)/2=$131.40

Which of the following statements correctly describes a difference between biomass-fired

power plants and traditional fossil-fuel-burning power plants, such as coal-fired plants?

Responses

A. The production of biomass does not release carbon dioxide but burning fossil fuels does.

B. The operational costs of biomass plants are very high when compared with traditional fossil fuel plants.

C. Biomass plants produce higher levels of mercury emissions than fossil fuel plants.

D. Biomass as a fuel source is not widely available all over the world while fossil fuels are abundant around the world.

B: The production of biomass plants is very expensive, and in some cases, the benefits may not be worth the costs. Transport and resource-gathering expenses are high and will likely be incurred every day. Compared to using fossil fuels, the cost of biomass energy is much higher.

Which of the following identifies the air pollutants most commonly released during the burning of biomass?

Responses

A. Lead ( Pb), carbon monoxide (CO), and nitric acid (HNO3)

B. Particulate matter ( PM ), ozone (03 ), and carbon monoxide (CO)

C. Carbon dioxide (CO2 ), particulate matter ( PM ), and carbon monoxide (CO)

D. Polychlorinated biphenyls ( PCBs), carbon dioxide (CO2 ), and chlorofluorocarbons ( CFCs)

C: All three pollutants are commonly released during the burning of biomass.

Which of the following is an environmental benefit associated with substituting ethanol for gasoline?

Responses

A. Ethanol is more energy efficient than gasoline.

B. Ethanol has a lower cost than gasoline.

C. Burning ethanol produces fewer air pollutants than burning gasoline alone.

D. Burning ethanol removes carbon dioxide from the atmosphere.

C: Ethanol is an oxygenated fuel, which has oxygen as part of its molecular structure. One environmental benefit of adding ethanol to gasoline or switching to 98 percent ethanol is that it produces lower carbon dioxide emissions and lower levels of hydrocarbons and nitrogen oxides than gasoline.

Which of the following best describes a potential advantage of using geothermal energy instead of solar farms for power generation?

Responses

A. Harnessing geothermal energy does not release hydrogen sulfide gas, whereas solar farms do.

B. Geothermal energy does not release greenhouse gases, whereas solar farms do.

C. Geothermal energy can be harnessed without destroying large tracts of habitat, whereas solar farms require large amounts of space.

D. Geothermal energy is easily accessible and can be harnessed in most parts of the world, whereas solar energy is difficult to harness.

C: Solar farms require large areas of land, including wildlife habitats and forests, to be cleared, whereas geothermal energy does not require large expanses of land for use.

Geothermal energy is used to run large and complex power stations as well as small and relatively simple pumping systems.

Which of the following most accurately explains how geothermal energy is produced and utilized in these applications?

Responses

A. Geothermal energy uses heat from the Sun to raise the Earth's surface temperatures to a point where these applications can heat homes and buildings.

B.Geothermal energy uses heat from the Sun to create atmospheric temperature gradients, which in turn power turbines to generate electricity.

C. Geothermal energy uses the natural insulating power of Earth to create temperature differentials that are used to heat buildings in the winter and cool them in the summer.

D. Geothermal energy cannot be tapped directly from heat generated by volcanoes or other geologically active areas.

C: Earth acts as a heat exchanger and can be used to generate heat in the winter and provide cooling in the summer. Ground-sourced heat pumps take advantage of the constant temperature of about 50°F that is found just a few feet below the ground's surface. In the summer, the pump moves heat from the building into the ground. In the winter, it does the opposite, providing warmed air and water to the heating system of the building.

Which of the following is required to convert geothermal energy into electricity?

Responses

A. Wind

B. Groundwater

C. Fossil fuel

D. Sunlight

B: Steam, which comes from groundwater, is evaporated by Earth's internal heat sources, and is used to turn turbines that generate electricity.

A hydrogen fuel cell-powered car driving on a highway is different from gasoline-powered cars because hydrogen fuel cell-powered cars only emit

Responses

A. carbon dioxide and hydrogen gas

B. carbon dioxide and heat

C. water vapor and hydrogen gas

D. water vapor and heat

D: Hydrogen fuel cells use the chemical potential energy stored in molecules of hydrogen and oxygen gas to generate electricity. This process produces water molecules and heat.

Which of the following best explains energy transformation in hydrogen fuel cells?

Responses

A. Methane reacts with oxygen to produce carbon and hydrogen atoms, which releases energy.

B. Hydrogen reacts with oxygen to produce water, which releases energy.

C. In the presence of sunlight, carbon dioxide reacts with water to produce sugar and oxygen, requiring energy.

D. Hydrogen chloride is dissolved in water, requiring energy.

B: Hydrogen reacts with oxygen to produce water and energy in a hydrogen fuel cell.

Which of the following is a disadvantage of using hydrogen fuel cells?

Responses

A. Hydrogen gas is not readily available on Earth.

B. The products of the reactions in hydrogen fuel cells damage the environment.

C. Hydrogen fuel cells are much less efficient in powering vehicles than internal combustion engines are.

D. Hydrogen fuel cells need to be very large to generate electricity.

A: Though abundant in the universe, hydrogen gas is relatively rare on Earth. Electricity is required to produce the hydrogen gas needed to make hydrogen fuel cells viable.

A state is looking to reduce the cost of transportation, which uses 7.10×1014 BTUs per year. Currently the cost of 106 BTUs is $20.00.

How much will the state save in one year if they implement regulations requiring all transportation methods to be 20% more efficient?

Responses

A. 2.10×107dollars

B. 2.84×109dollars

C. 1.42x1014dollars

D. 2.84x1015dollars

B: The state is requiring a 20% reduction in current energy use. That would make the current energy use (7.10×1014BTUsx0.20)=1.42x1014BTUs. If the current cost of one million BTUs is $20, then 1.42×1014/1×106=1.42×108*$20=$2.84×109, or 2.84 billion dollars in savings.

Burning one gallon of gasoline in a car releases approximately 20 pounds of CO2 into the atmosphere. One person drives 60,000 miles in a car that averages 30 miles per gallon (mpg), while another person drives 60,000 miles in a car that averages 20 mpg. Over the course of the 60,000 miles, how many fewer pounds of CO2 are released by the 30 mpg car than by the 20 mpg car?

20,000