Generating Electricity and Energy Resources

Generating Electricity

  • Force, such as moving water, pressurized steam, or wind, spins a turbine.
  • The spinning turbine turns a shaft connected to a generator.
  • The generator, with magnets spinning past copper wire coils, generates electricity.
  • Generators convert mechanical energy into electrical energy.
  • Electrical output travels through the network to homes, schools, and businesses.
  • Electrical energy is unique because its production can be controlled, and it can travel long distances.
  • Engineers design devices to convert electrical energy into motion, thermal energy, or light.
    • Example: An electric blender converts electrical energy into motion.
    • Example: A toaster converts electrical energy into thermal energy.

Non-Renewable Resources

  • Non-renewable energy resources include coal, natural gas, oil, and nuclear energy.
  • These resources cannot be replaced once used up.
  • Fossil fuels:
    • Oil: Liquid fuel, used to produce gasoline and diesel for vehicles and plastics manufacturing. Extracted through wells.
    • Natural gas: Used for cooking and heating. Consists mostly of methane, found near oil deposits, and extracted through wells.
    • Coal: Solid fossil fuel, used for heating and power generation. Dug up from the ground; found in fossilized swamps beneath sediment layers.
  • Nuclear energy: Comes from radioactive elements, mainly uranium, extracted from mined ore and refined into fuel.
  • Approximately 80% of global energy comes from fossil fuels.
  • Fossil fuels are energy-rich and relatively cheap to process.
  • Burning fossil fuels releases carbon dioxide into the atmosphere, contributing to global warming.

Renewable Resources

  • Renewable energy is naturally replenished and can't be depleted.
  • Important renewable resources include:
    • Wind
    • Solar
    • Tidal
    • Biomass
    • Hydro
    • Geothermal
  • The sources are always available, addressing sustainability concerns.
  • Important to provide enough energy to meet needs, heat homes, and power cities.
  • Consider how long these resources can be used.
  • Renewable resources also produce clean energy, meaning less pollution and fewer carbon emissions that contribute to climate change.
  • Some challenges exist with using renewable resources, such as less reliability compared to non-renewable energy due to daily or seasonal changes.
  • Scientists continuously address these challenges to improve accessibility and reliability of renewable energy.
  • Biomass includes organic material from plants and animals, such as wood, crops, vegetable oils, and animal manure.
    • This organic material has absorbed energy from the sun, which is then released as heat energy when burned.
  • Hydropower uses flowing water to generate electricity.
    • Water flows turning turbines, generating electricity
    • Power plants use the flow of rivers and streams to turn turbines, generating electricity.
  • Geothermal energy comes from heat generated deep within the Earth's core.
    • Geothermal reservoirs are found at tectonic plate boundaries near volcanic activity or deep underground.
    • Harnessed by drilling wells to pump hot water or steam to power plants for heating and electricity.
  • Wind energy generates electricity by turning wind turbines.
    • Wind pushes the turbine's blades and a generator converts mechanical energy into electricity, supplying power to homes and buildings, and can be stored in the power grid.
  • Solar energy - photovoltaic cells convert solar energy from the sun into electricity.
    • Individual cells generate enough power for a calculator, but combining them into solar panels or larger arrays provides more electricity.
  • Tidal energy is power produced by the surge of ocean waters during the rise and fall of tides and currents; not widely used yet.
  • Searching for the right method of using renewable resources is increasingly important.
  • Switching to renewable energy sustains the growing population and provides a cleaner environment for future generations.

Comparing Renewable and Non-Renewable Resources

  • Depletion:
    • Renewable: Cannot be depleted over time.
    • Non-Renewable: Deplete over time.
  • Sources:
    • Renewable: Sunlight, water, wind, geothermal (hot springs).
    • Non-Renewable: Fossil fuels (coal and petroleum).
  • Environmental Impact:
    • Renewable: Low carbon emissions and footprint.
    • Non-Renewable: Comparatively higher carbon footprint and emissions.
  • Cost:
    • Renewable: High upfront cost.
    • Non-Renewable: Comparatively lower upfront cost.
  • Infrastructure:
    • Renewable: Expensive and not easily accessible in most countries.
    • Non-Renewable: Cost-effective and accessible in most countries.
  • Area Requirements:
    • Renewable: Requires a large land/offshore area (wind and solar farms).
    • Non-Renewable: Comparatively lower area requirements.