EVR 2001 EXAM 2 STUDY GUIDE
Kinetic - Answers :energy of motion. Wind, for example, is solar energy converted into
moving air.
Potential - Answers :energy of position. Can be converted into kinetic energy by
allowing the object/substance to roll/flow/fall to a lower elevation.
Radiant - Answers :energy contained in electromagnetic radiation, e.g. solar radiation
Chemical - Answers :energy stored in molecular bonds. Photosynthesis converts radiant
energy into chemical energy.
energy quality - Answers :how easy it is to capture and use various types of energy
sources. Relates to energy density(amount of energy per unit volume).
Energy - Answers :Ability to do work (an amount), W or E, Joule (J)
Power - Answers :Rate at which energy is consumed or produced, Watt= 1 Joule,
Horsepower
Fossil Fuels - Answers :supply 88% of the world's commercial energy needs. Coal,
petroleum (oil and oil products), and natural gasAbout 81% in U.S.
What petroleum is used for... - Answers :Mostly Gasoline
Natural Gas - Answers :Often found alongside coal and oil reservesPrimarily methane
(CH4)The "cleanest" fossil fuel- half as much CO2as coalSometimes considered a
transition fuelon the path to renewable electricity. Utilization is quickly increasing.Used
primarily for electricity generation using gas turbines, but also for heating and
cookingNon-fossil methane is also produced in wetlands, wastewater treatment plants,
feed lots, and landfills. If those sources are tapped, it is called biogas or landfill gas.
This would also reduce climate change, since methane is a stronger greenhouse gas
than CO2.
Internal combustion engines and Gas turbines - Answers :Natural gas or syngas
turbines, vehicle combustion enginesThese release the energy contained in the fuel
through controlled burning (combustion). The resulting high-pressure gases are
converted into electrical or mechanical energy (without heating up water first).Discrete
ignitions (car engine) vs. continuous burning (turbine)
Combustion - Answers :release the energy contained in the fuel through controlled
burning
, Combined cycle power plants combine what? - Answers :combine gas turbines with
steam turbines to increase efficiency.They "recycle" the heat from a first pass through a
conventional gas turbine to drive a secondary steam turbine
Nuclear fuels - Answers :Primarily heavily processed uranium oreMined in surface and
underground minesU-235occurs naturally at 0.7% of uranium ore, but must be enriched
to 3%
Plutonium - Answers :is produced as a byproduct in reactors, which can be extracted to
provide additional fuel
Problem with Storage for Radioactive Wastes - Answers :we have no permanent
storage for it
How long will fossil and nuclear fuels last? - Answers :Coal is abundant - reserves will
likely last 200+ years
oil and natural gas- Cheap conventional sources of oil and natural gas are steadily
being exhausted. Horizontal drilling & fracking of shale deposits, mining of oil
sandsGreater environmental impacts than conventional drilling - more CO2emissions,
water consumption and pollution, air pollution, land degradation
Nuclear fuel- is relatively abundant. Technology also exists to "breed" nuclear
fuels.Unknown whether nuclear will play a significant role in the future due to economics
and public opposition
Biomass - Answers :Wood, animal dung, garden waste, agricultural waste, forestry
waste, As recently as 1850, wood supplied 90% of the fuel used in the United States.In
poor countries it is still a major source of energy and its use can result in habitat
destruction.
Problems with Biomass - Answers :Low energy density, use reduces in-situ
decomposition, potentially unsustainable
Ethanol - Answers :Food crops (corn, sugar cane) are often used to produce ethanol(a
transportation fuel)
In the future, ethanol could be made from cellulosic material such as wood chips, straw,
or from switchgrass grown where crops can't be.
Algae-based biofuels are... - Answers :are a promising approach for the future.
Concentrated Solar Thermal (CSP) - Answers :Large space requirementsNo need for
mines for fuel extraction, thoughWell-suited for desert environments with minimal cloud
cover and cheap land prices
still rare
Solar Energy Advantages - Answers :Inexhaustible
Kinetic - Answers :energy of motion. Wind, for example, is solar energy converted into
moving air.
Potential - Answers :energy of position. Can be converted into kinetic energy by
allowing the object/substance to roll/flow/fall to a lower elevation.
Radiant - Answers :energy contained in electromagnetic radiation, e.g. solar radiation
Chemical - Answers :energy stored in molecular bonds. Photosynthesis converts radiant
energy into chemical energy.
energy quality - Answers :how easy it is to capture and use various types of energy
sources. Relates to energy density(amount of energy per unit volume).
Energy - Answers :Ability to do work (an amount), W or E, Joule (J)
Power - Answers :Rate at which energy is consumed or produced, Watt= 1 Joule,
Horsepower
Fossil Fuels - Answers :supply 88% of the world's commercial energy needs. Coal,
petroleum (oil and oil products), and natural gasAbout 81% in U.S.
What petroleum is used for... - Answers :Mostly Gasoline
Natural Gas - Answers :Often found alongside coal and oil reservesPrimarily methane
(CH4)The "cleanest" fossil fuel- half as much CO2as coalSometimes considered a
transition fuelon the path to renewable electricity. Utilization is quickly increasing.Used
primarily for electricity generation using gas turbines, but also for heating and
cookingNon-fossil methane is also produced in wetlands, wastewater treatment plants,
feed lots, and landfills. If those sources are tapped, it is called biogas or landfill gas.
This would also reduce climate change, since methane is a stronger greenhouse gas
than CO2.
Internal combustion engines and Gas turbines - Answers :Natural gas or syngas
turbines, vehicle combustion enginesThese release the energy contained in the fuel
through controlled burning (combustion). The resulting high-pressure gases are
converted into electrical or mechanical energy (without heating up water first).Discrete
ignitions (car engine) vs. continuous burning (turbine)
Combustion - Answers :release the energy contained in the fuel through controlled
burning
, Combined cycle power plants combine what? - Answers :combine gas turbines with
steam turbines to increase efficiency.They "recycle" the heat from a first pass through a
conventional gas turbine to drive a secondary steam turbine
Nuclear fuels - Answers :Primarily heavily processed uranium oreMined in surface and
underground minesU-235occurs naturally at 0.7% of uranium ore, but must be enriched
to 3%
Plutonium - Answers :is produced as a byproduct in reactors, which can be extracted to
provide additional fuel
Problem with Storage for Radioactive Wastes - Answers :we have no permanent
storage for it
How long will fossil and nuclear fuels last? - Answers :Coal is abundant - reserves will
likely last 200+ years
oil and natural gas- Cheap conventional sources of oil and natural gas are steadily
being exhausted. Horizontal drilling & fracking of shale deposits, mining of oil
sandsGreater environmental impacts than conventional drilling - more CO2emissions,
water consumption and pollution, air pollution, land degradation
Nuclear fuel- is relatively abundant. Technology also exists to "breed" nuclear
fuels.Unknown whether nuclear will play a significant role in the future due to economics
and public opposition
Biomass - Answers :Wood, animal dung, garden waste, agricultural waste, forestry
waste, As recently as 1850, wood supplied 90% of the fuel used in the United States.In
poor countries it is still a major source of energy and its use can result in habitat
destruction.
Problems with Biomass - Answers :Low energy density, use reduces in-situ
decomposition, potentially unsustainable
Ethanol - Answers :Food crops (corn, sugar cane) are often used to produce ethanol(a
transportation fuel)
In the future, ethanol could be made from cellulosic material such as wood chips, straw,
or from switchgrass grown where crops can't be.
Algae-based biofuels are... - Answers :are a promising approach for the future.
Concentrated Solar Thermal (CSP) - Answers :Large space requirementsNo need for
mines for fuel extraction, thoughWell-suited for desert environments with minimal cloud
cover and cheap land prices
still rare
Solar Energy Advantages - Answers :Inexhaustible
