Energy Sources and Environmental Impact

Energy Sources and Environmental Impact

  • Dependency on Petroleum: Current heavy reliance on petroleum in the U.S. is a recent trend.
  • Formation of Fossil Fuels: Petroleum and natural gas likely formed from marine organisms over 500 million years.
  • Composition of Hydrocarbons: Petroleum consists of hydrocarbon chains, primarily carbon and hydrogen.

Natural Gas and Fracking

  • Natural Gas Constituents: Mainly methane; also includes ethane, propane, and butane.
  • Shale Deposits: High reserves in shale; challenges include low permeability affecting gas flow.
  • Hydraulic Fracturing (Fracking): Method used to access shale gas, raises environmental concerns such as groundwater contamination.

Petroleum Use & Processing

  • Fractional Distillation: Separates petroleum into usable fractions based on boiling points:
    • Gasoline (C5-C10)
    • Kerosene (C10-C18)
    • Diesel Fuel (C15-C25)
  • Pyrolytic Cracking: Increases gasoline yield from kerosene.
  • Lead as an Antiknock Agent: Tetraethyl lead was commonly added to gasoline, phased out due to environmental concerns.

Coal: Composition and Energy

  • Formation of Coal: Created from plant remains under high pressure and heat, maturing through stages (lignite, subbituminous, bituminous, anthracite).
  • Energy from Coal: Higher carbon content increases energy yield; anthracite is the most valuable.
  • Environmental Concerns: Coal combustion produces pollutants (e.g., sulfur dioxide) and contributes to acid rain and climate change.

Greenhouse Effect and Climate Change

  • Greenhouse Gases: Water vapor and CO2 trap heat, affecting Earth's climate.
  • Impact of CO2 Levels: Increased atmospheric CO2 contributes to global warming, with potential temperature increases of 3°C.

Alternative Energy Sources

  • Hydrogen Fuel: Burns cleanly with water as the only byproduct, but presents production, storage, and transportation challenges.
  • Coal Gasification: Converts solid coal to syngas, which can be used as a cleaner fuel.
  • Wind Power: Growing potential for electricity generation; requires infrastructure improvements for large-scale use.

Conclusion

  • Future Energy Strategies: Must balance fossil fuel conservation with the development of alternative energy sources, considering environmental impacts.