Energy (topic 1 )

• Non renewable resources :


  Coal, oil, (natural) gas
• renewable resources:


  solar, wind, water waves, hydro-electricity, bio-fuel, tides, geothermal
• Transport using Non Renewable resources 


  Petrol and diesel powered cars use fuel created from oil

  Coal is used in some old fashioned steam trains
• Transport using renewable resources 


  Vehicles that run on pure bio fuel or a mix of bio fuel and petrol (only the bio fuel bit is renewable though)
• Heating using non renewable sources

  Natural gas is the most widely used fuel to heat homes in the UK (heats water for radiators)

  Coal is also commonly burnt in fire places
• Wind power: benefits

  • no fuel costs and minimal running costs
  • no pollution (except for the little produced when they are manufactured)
  • no permanent damage to the landscape
  • renewable energy resource
• Wind power : problems

  • spoils the view
  • need about 1500 wind turbines to replace one coal-fired power station- need a lot of space
  • very noisy
  • initial costs are quite high
  • wind turbines only produce electricity 70-85% of the time, and its impossible to increase supply when there's extra demand
• Solar cells:

  • they generate electricity directly from sunlight
  • often used in remote places (e.g the Australian outback), and to power road signs and satellites
  • usually used to generate electricity on a relatively small scale
• Solar cells: benefits

  • No pollution (although they do use a lot of energy to manufacture in the first place )
  • after initial costs energy is free and running costs are almost nothing
• solar cells : problems

  • Can only produce energy when there's sunlight (wont work at night or when its cloudy )
  • high initial costs
  • cant increase power output when there is extra demand
• Geo thermal power

  • possible in volcanic areas or where hot rocks lie quite close to the surface
• Geothermal power: benefits

  • reliable, free source of energy
  • does very little damage to the environment
  • used to generate electricity or directly heat buildings
• Geothermal power : problems

  • not many suitable locations
  • cost of building the power plant is often high compared to the amount of energy it produces
• Hydroelectric


  requires the flooding of a valley by building a big dam, water is allowed out of turbines
• Hydroelectric : benefits

  • no pollution
  • can provide an immediate response to increased demand
  • high initial costs
  • reliable (except during droughts)
• Wave pollution

  lots of small wind powered turbines required located around the coast, the moving turbines are connected to a generator
• Wave power :benefits

  • no pollution
  • no fuel costs and minimal running costs
  • likely never be used on a large scale but usefull on small islands
• Wave power : problems

  • disturbing the seabed and habitats
  • spoils the view
  • hazard to boats
  • fairly unreliable
  • high initial costs
• Tidal barrages

  • big dams built across river estuaries with turbines in them, as the tide comes it fills up the estuary, the water is then allowed out of the turbines at a controlled speed
  • tides are produced by the gravitational pull of the sun and moon
• Tidal barrages: benefits

  • no pollution
  • tides are pretty reliable (happen twice a day ) but the height of them is unpredictable sometimes
  • no fuel costs and minimal running costs
  • has the potential to produce significant amounts of energy
• Tidal barrages : problems

  • preventing free access by boats
  • spoiling the view
  • altering the habitat
  • moderately high initial costs
• Bio fuels

  • created from either plant products or animal dung
  • can be solid, liquid or gas and can be burnt to produce electricity or to run cars
  • supposedly carbon neutral although this is up for debate
• Bio fuels : benefits

  • fairly reliable however they cannot respond to immediate energy demands
  • can be stored for when they are needed
• Bio fuels : problems

  • high cost to refine them
  • requires space and water to grow the crops required
  • in some regions forests have been cleared to make room to grow said crops resulting in in the loss of habitats
• Non renewable:

  • fossil fuels and nuclear energy are reliable, theres enough to meet current demand and they are extracted from the earth at a quick enough rate that power plants always have fuel in stock
  • these fuels are slowly running out
  • low running costs and low fuel extraction costs making fossil fuels a cost effective way to produce energy
• Problems of Fossil fuels

  • release CO2 when burned contributing to the green house effect
  • burning coal and oil releases sulfur dioxide which causes acid rain
  • coal mining makes a mess of the landscape
  • oil spillages cause serious environmental problems
• Problems of Nuclear power

  • clean but the nuclear waste is very dangerous and difficult to dispose of
  • overall cost of nuclear power is high due to the cost of the power plant
  • carries the risk of a major catastrophe
• The Uk's use of Fossil fuels

  • some of our electricity is produced using fossil fuels and nuclear power
  • we also burn oil to use as petrol/diesel and oil to heat homes and cook food
  • electricity use in the Uk has been decreasing due to appliances becoming more efficient and people becoming more careful about energy use in their homes
• Why use renewable sources?

  • burning fossil fuels is very damaging to the environment
  • non renewable sources will run out
  • pressure from other countries and the public has made the government put targets in place for using renewable resources
• The use of renewables is limited...

  • building new power plants costs money
  • many people do not want the new power plants built near them
  • some of these energy resources are not as reliable as traditional fossil fuels
  • research on improving the reliability and cost takes time and money
  • making personal changes (e.g. having an electric car) can be expensive
• What are the eight energy stores ?


  • Thermal
  • Kinetic
  • Chemical
  • Gravitational potential
  • Elastic potential
  • Nuclear
  • Magnetic
  • Electrostatic
• what is a system


  a single object or a group of objects that you are focusing on
• What happens when a system changes ?


  energy is transferred

  it can be transferred into or out of the system, between different objects in the system or between different types of energy stores
• What are closed systems?

  systems where neither matter nor energy can leave or enter

  the net change in the total energy of a closed system is always zero
• What are the 4 energy transfers?


  • mechanically (by force)
  • electrically (work done or by moving charges )
  • by heating
  • by radiation (e.g. light or sound)
• Work done is just another way of sayinf energy transferred

  Work can be done when current flows or by force moving an object
• When is energy tranferred to the kinetic store of an object ?


  when that object speeds up (energy is transferred away from its kinetic store when it slows down)
• An objects kinetic energy depends on its mass and speed:

  the greater its mass and the faster its going the more energy there will be in the kinetic store
• Lifting an object in a gravitational field requires work. This causes a transfer of energy to the gravitational potential energy store of the raised object. The higher the object is lifited the more energy will be transferred into this store.
• The amount of energy in a G.P.E store depends on the objects mass, its height and the strength of the gravitational field the object is in