3.3 People, Energy, and Minerals

• Nonrenewable resources


  Natural resources that are present in limited supplies and are depleted as they are used
• Nonrenewable resources


  • Minerals such as aluminum, tin, and copper
  • Fossil fuels including coal, oil, and natural gas
• Fossil fuels are organic chemicals created by living organisms that were buried in sediments millions of years ago and transformed to energy-rich compounds
• Because fossil fuels take so long to form, they are essentially nonrenewable resources
• Coal


  The most abundant fossil fuel in the world, found primarily in the Northern Hemisphere
• According to the World Resources Institute, known world coal reserves could last for more than 200 years at the present rate of consumption
• Coal resources currently too expensive to develop have the potential to provide enough coal to last for 1000 or more years at current consumption rates
• Coal consumption has surged in recent years, particularly in the rapidly growing economies of India and China
• Surface mining


  The extraction of mineral and energy resources near Earth's surface by first removing the soil, subsoil, and overlying rock strata
• Subsurface mining


  The extraction of mineral and energy resources from deep underground deposits
• Surface mining


  • Cheaper, safer
• Subsurface mining


  • Less destructive to the environment
• Acid mine drainage


  Pollution caused when sulfuric acid and dangerous dissolved materials, such as lead, arsenic, and cadmium, wash from coal and metal mines into nearby lakes and streams
• Mountaintop removal


  • Air pollution (more than that of oil and natural gas)
  • Greenhouse gas emission (more CO2 than oil and natural gas)
• Fluidized-bed combustion


  A clean-coal technology in which crushed coal is mixed with limestone to neutralize acidic compounds produced during combustion
• Petroleum (crude oil)


  A liquid composed of hundreds of hydrocarbon compounds
• Oil


  Used to produce petrochemicals, compounds used to make products such as fertilizers, plastics, paints, pesticides, medicines, and synthetic fibers
• Petroleum refining


  The compounds are separated into different products—such as gases, jet fuel, heating oil, diesel, and asphalt—based on their different boiling points
• Natural gas


  Contains only a few hydrocarbons: methane and smaller amounts of ethane, propane, and butane
• Propane and butane


  Separated from the natural gas, stored in pressurized tanks as a liquid called liquefied petroleum gas, and used primarily in rural areas as fuel for heating and cooking
• Methane


  Used to heat residential and commercial buildings, to generate electricity in power plants, and for a variety of purposes in the organic chemistry industry
• Because it is a gas and less dense than a liquid, natural gas costs four times more to transport through pipelines than crude oil
• Environmental impacts of oil and natural gas


  • Air pollution (acid deposition) and GHG emissions (although less than that of coal)
  • Leaks (for natural gas, which can lead to massive explosion)
  • Spills (for oil, which can create environmental damage, particularly in aquatic ecosystems, where an oil slick can travel great distances)
• Nuclear energy


  The energy released by nuclear fission or fusion

  
• Nuclear fission


  The splitting of an atomic nucleus into two smaller fragments, accompanied by the release of a large amount of energy

  
• Nuclear fusion


  The process that powers the sun and other stars where two small atoms are combined, forming one larger atom of a different element
• Nuclear reactor


  A device that initiates and maintains a controlled nuclear fission chain reaction to produce energy for electricity
• Spent fuel (radioactive waste)


  Used fuel elements that were irradiated in a nuclear reactor
• Meltdown


  At high temperatures, the metal encasing uranium fuel can melt, releasing radiation

  
• Low-level radioactive wastes


  Solids, liquids, or gases that give off small amounts of ionizing radiation
• High-level radioactive wastes


  Radioactive solids, liquids, or gases that initially give off large amounts of ionizing radiation
• Renewable resources


  Resources that are replaced by natural processes and that can be used forever, provided they are not overexploited in the short term
• Active solar heating


  A system of putting the sun's energy to use in which collectors absorb solar energy and pumps or fans distribute the collected heat

  
• Passive solar heating


  A system of putting the sun's energy to use that does not require mechanical devices to distribute the collected heat

  
• Photovoltaic (PV) solar cell


  A wafer or thin film of solid-state materials, such as silicon or gallium arsenide, that is treated with certain metals in such a way that the film generates electricity when solar energy is absorbed

  
• Solar thermal electric generation (concentrated solar power or CSP)


  A means of producing electricity in which the sun's energy is concentrated using mirrors or lenses onto a fluid-filled pipe; the heated fluid is used to generate electricity

  
• Biomass energy


  Energy that uses plant and animal material as fuel
• Wind energy


  Electric energy obtained from surface air currents caused by the solar warming of air
• Hydropower


  A form of renewable energy that relies on flowing or falling water to generate electricity
• Geothermal energy


  Energy from Earth's interior, used for space heating or generation of electricity