Energy

• Ways of energy transfer:

  • Transferred mechanically by a force acting over a distance
  • Transferred by heating due to temperature difference
  • Transferred by propagation of EM waves
  • Transferred by propagation of mechanical sound waves
  • Transferred electrically by an electric current
• Energy trilemma:

  • Environmental: ensure energy is renewable and have minimum impact on environment
  • Energy security: Having different sources to ensure supply is not disrupted
  • Competitive pricing: Ensure energy remains affordable
• Energy from fossil fuels:

  • Examples include petroleum, natural gas, wood and coal
  • Has chemical potential energy that gets converted to heat when burnt
  • Advantages: Is reliable and has cheaper cost of production
  • Disadvantages: Non renewable energy source and can cause environmental pollution through gases produced apon burning
• Energy from nuclear fuels:

  • Nuclear fuels undergo nuclear reactions such as fission to generate electrical power
  • Advantages: Reduce greenhouse gas emissions that contribute to global warming, reliable in supplying uninterrupted power
  • Disadvantage: Non-renewable energy source and carries risk of accidents and pollution from improper disposal of radioactive waste
• Energy from biofuels:

  • Examples such as ethanol, biodiesel and biogas which are derived from biomass
  • Chemical potential store is transferred to internal stores when fuel is heated
  • Advantages: Is renewable energy source, widely available and has relatively cheaper cost of production
  • Disadvantages: Gases produced through combustion causes global warming
• Energy from wind:

  • Energy in kinetic store of wind transferred to electrical store in motor (got more steps but simplified)
  • Advantage: Renewable and cleam method of producing electricity
  • Disadvantage: Energy supply not constant, causes noise pollution and loss of habitat due to clearing of land
• Energy for tides:

  • Energy in kinetic store of water is converted to electrical power
  • Advantage: Renewable source that is more reliable than wind and sun, is a clean method to produce energy
  • Disadvantage: High cost to build tide barriers and generators, Marine life will be affected due to change in currents, noise and emission of EM fields
• Energy from hydropower:

  • Gravitational store of water is converted to electrical power
  • Advantage: renewable source of energy that can be continuously produced, clean method of energy production
  • DIsadvantage: High cost of building structures, may damage environment due to damming of river
• Energy from geothermal reservoirs:

  • Internal energy stores of earth's core heats water that generates power in turbines
  • Advantages: Renewable and clean source of energy
  • Disadvantages: Causes environmental pollution through release of poisonuos gases and is not widely available
• Energy from solar power:

  • Energy in nuclear store of sun generates electricity in solar panels
  • Advantages: Renewable and clean source of energy
  • Disadvantages: Not always available as it depends on presence of sunlight, takes up a lot of space