Chapter 12: Non-Renewable Energy Sources

Chapter 12: Non-Renewable Energy Sources

• Global fossil fuel use: 81% of total energy, utilizing 570 exajoules annually.
• Renewable energy use: 14%.
• Leading energy consumers: China (highest annual), US (highest per capita).
• Commercial energy: purchased and sold, including fossil fuels, nuclear, and renewables.
• Subsistence energy: directly obtained from natural resources (firewood, foraging, etc.).
• US energy consumption patterns: Petroleum highest, followed by natural gas, then coal; with a trend towards less reliance on coal and oil for energy.
• Annual US energy consumption: 103 exajoules; similar fossil fuel dominance to global patterns.
• Transportation: consumes nearly 30% of US energy, primarily due to cars, trucks, etc.
• US fuel economy: declined from past levels, then later saw improvements to reduce consumption and emissions.

Electricity Generation and Efficiency

• Electricity generation: accounts for ~40% of US energy use.
• Energy carriers: move energy in usable forms (electricity).
• Thermal power plants: convert fuel potential energy into electricity using turbines and generators.
• Steam generation: water boils to create steam, driving turbines connected to generators.
• Coal-fired electricity: combustion transfers heat to water generating steam, driving turbines, generating electricity.

Cogeneration

• Cogeneration: generates electricity and useful heat from a single fuel source, maximizing efficiency.
• Combined cycle systems: utilize exhaust gases from gas turbines to generate additional steam and thus more electricity.

Fossil Fuels

• Coal: solid fuel formed from ancient plant matter; major reserves in the US, Russia, China, and India.
  • Advantages: energy-dense, plentiful, inexpensive, easy to extract by surface mining.
  • Disadvantages: impurities, pollutant emissions (Hg, Pb, As), ash, CO₂ release.
• Peat: precursor to coal; formed in bogs where decaying vegetation accumulates.
• Coal types: lignite < bituminous < anthracite (increasing energy density).
• Petroleum: liquid mixture of hydrocarbons, water, and sulfur; cleaner than coal than coal and convenient for use and transport.
  • Advantages: energy-dense, relatively clean burning.
  • Disadvantages: CO₂ release, potential leaks during extraction and transport, air and water pollution.
• ANWR: Arctic National Wildlife Refuge (ANWR); debate about oil extraction vs. environmental impact.
• Natural gas: cleanest fossil fuel; mostly methane; used for electricity, industrial processes and in residences.
  • Advantages: low emissions, fewer impurities.
  • Disadvantages: still emits greenhouse gases (methane), potential groundwater contamination from extraction (fracking).

Other Fossil Fuels

• Oil sands and liquid coal: bitumen (degraded petroleum) and CTL (coal-to-liquids) technologies.
• Energy intensity: energy use per unit of GDP; decreasing energy use per capita is beneficial to the environment.
• Hubbert curve: graphical representation of a resource's production over time; used to predict oil production peaks.
• Peak oil: highest point of global oil production.

Nuclear Energy

• Nuclear fission: splitting atomic nuclei to release energy.
• Uranium-235: main fuel source for nuclear power plants.
• Chain reaction: fission triggers a self-sustaining process.
  • Advantages: no air pollution.
  • Disadvantages: accidents (Chernobyl, Fukushima), waste disposal concerns, potential for misuse of material.
• Radioactive waste: high-level (spent fuel rods) and low-level (protective clothing, tools); safe disposal methods are crucial.
• Half-life: time required for half a substance to decay.
• Nuclear fusion: combining lighter nuclei to release energy (theoretical future energy source).

Chapter 13: Energy Conservation and Increasing Efficiency

• Energy conservation: reducing energy consumption.
• Energy efficiency: maximizing the output of useful energy.
• Tiered rate system: pricing electricity based on usage levels (higher rate for higher use) in order to encourage conservation.
• Peak demand: highest energy usage at a time.
• Sustainable design: improving building efficiency and use of renewable resources (Passive solar technology, thermal mass).
• Passive solar Design: utilizing natural sunlight for heating and cooling (overhangs, window placements, thermal mass).

Renewable Energy

• Renewable/Nondepletable Energy Sources: energy that can be regenerated (Potentially renewable) or is effectively limitless on Earth's time scale.
• Biomass: energy from plant matter; modern carbon vs fossil carbon; sustainable use is essential
  • Solid biomass (wood, charcoal, manure).
• Biofuels: liquid fuels from biomass (ethanol, biodiesel).
• Hydroelectric power: electricity generated using moving water.
  • Run-of-the-river: hydroelectricity using natural river flow without dam storage.
  • Water impoundment (dams): storing water behind a dam to generate power; benefits and environmental impacts (ecosystem disruptions, flooding land).
• Tidal energy: energy from water movement caused by tides.
• Solar power: harnessing sunlight energy.
  • Active solar: photovoltaic panels, water heaters.
  • Concentrating Solar Power (CSP): use of mirrors or lenses to concentrate sunlight for thermal energy production.
• Wind power: using wind turbines to generate electricity.
• Geothermal energy: heat energy from within the Earth.
  • Direct heat use.
  • Electricity generation via steam turbines.
  • Ground source heat pumps.
• Hydrogen fuel cells: converting hydrogen into electricity chemically.
• Smart Grid: a digital grid that optimizes energy distribution and consumption.
• Energy Future Consideration: balancing practicality requirements against environmental responsibility to achieve environmentally conscious energy strategies.