how can we obtain energy

• fossil fuel as energy resource

  example of fossil fuels are pertoleum, natural gas, wood and coal

  fossil fuels have energy in the chemical potential store

  when fuel is burnt in air for cooking food, heating transfers energy from the chemical potential store of the fuel to the internal store of the food and surroundings
• nuclear fuels as energy resource


  nuclear fuels undergo nuclear reactions to release energy, most nuclear fuels undergo a nuclear reaction called nuclear fission

  during nuclear fission, the nuclei of the nuclear fuel splits into two or more parts, energy is transferred from the nuclear store of this nuclei to the large kinetic stores of these two or more moving parts which in turn increases the temperature of the water surrounding the fuel rods, producing steam

  electrical power is generated when steam moves the turbines in a nuclear reactor
• biofuels as energy resource


  examples of biofuels are ethanol, biodiesal, and biogas, all derived from biomass. biomass comes for living materials such as corn and animal manure

  biofuels have energy in the chemical potential stores

  when cooking, heating transfers energy from the chemical potential store of the biofuel to the internal store of the food and surroundings
• wind as energy resource

  energy in the kinetic store of the wind is transferred mechanically to the kinetic store of the rotor blades of the wind turbine

  electrical power is generated when the rotor blades connected to the generators rotate
• tides as energy resource

  water movements from changing high and low tides causes the turbines below the water surface to rotate

  energy in the kinetic store of the water is transferred mechanically to the kinetic store of the turbines

  electrical power is generated when the turbines connected to the generators rotate
• hydropower as energy resource

  can be obtained from water behind hydroelectric dams

  water behind hydroelectric dams has energy in the gravitational potential store. by releasing the water and letting it flow downwards, energy in the gravitational potential store is transferred mechanically to the kinetic store of the water

  the flowing water causes turbines to spin, electrical power is generated when the turbines connected to the generators rotate
• geothermal reservoirs as energy resource

  in volcanic regions, geological force push large amounts of hot molten rocks near the earth's surface, these places are known as geothermal hotspots

  water that makes its way to these geothermal hotspots is heated and subjected to great pressure

  heated water has large amounts of energy in the internal store, the water is forced to the surface as boiling water and steam to drive turbines
• solar power as energy resource

  comes from the sun, sun has energy in the nuclear store and the energy is transferred by electromagnetic waves from the sun to the internal stores of solar panels

  when the solar panels are irradiated by sunlight, electricity is generated
• advantages of fossil fuels

  more reliable than other factors as fossil fuels do not rely on environmental factors

  cheaper cost of production compared to other resources
• advantages of nuclear fuels

  low carbon energy, do not produce a lot of greenhouse gases that causes global warming

  higher reliability in supplying uninterrupted power
• advantages of biofuel

  renewable energy resource

  widely available on a large scale

  relatively cheaper cost of production compared to other resources
• advantages of wind

  renewable energy resource

  clean method of producing electricity, no harmful produced
• advantages of tides

  renewable energy resource

  more reliable than wind or sun

  clean method of producing, no harmful gases produced
• advantages of hydropower

  renewable energy and water can be continually regenerated

  clean method of producing electricity, no harmful gases are produced
• advantages of geothermal reservoirs

  renewable energy resource

  clean source of naturally available energy in the internal store as long as you are in a volcanic region
• advantages of solar power

  renewable energy resource

  clean method of producing electricity, no harmful processes are produced
• disadvantages of fossil fuels

  non renewable energy resource

  environmental pollution from the gas produced, contributing to global warming
• disadvantages of nuclear fuels

  non renewable energy resource

  risk of accidents and pollution due to improper disposal of radioactive waves
• disadvantages of biofuels

  environmental pollution due to the harmful gases produced that contributes to global warming
• disadvantages of wind

  intermittent power as it is not easy to find places where there is a steady wind blowing at a speed of 20-25km/h

  noise pollution and loss of habitat for wildlife
• disadvantages of tides

  high cost of building, marine life affected due to alterations of water currents, noise and emission of electromagnetic fields
• disadvantages of hydropower

  high cost of building

  possible damage to the environment surrounding the river
• disadvantages of geothermal resrvoirs

  environmental pollution due to the release of poisonous gas such as hydrogen sulfide

  not widely available, only found in certain areas in the world
• disadvantages of solar power

  not always available, weather dependant

  takes up space