9. Energy resources

• Heat - anything above absolute zero degrees emit heat energy. Heat energy moves down a temperature gradient.
• Light - composed of photons and defined by its wave length
• Sound - vibrations of air, liquids, solids
• Potential - Stored energy/energy stored at a raised height
• Kinetic - energy of movement. defined by velocity + mass
• Electrical - movement of electrons in a circuit
• Chemical - Form of potential energy which has to go through transformation to be useful (coal, oil, gas)
• Nuclear - energy stored in nucleus of an atom
• Energy = measure of workdone
• Power = measure of workdone per unit time

  power = energy/time
• Uses of energy

  • Domestic appliances
  • Fuel
  • Clothes production
  • Farming
  • Water
  • Heating
  • Power
  • Cooking
• Why does per capita energy vary from country to country?

  • Affluence - e.g. beach holiday
  • Types of industry - e.g. China
  • Availability of resources
  • Infrastructure for energy
  • Environmental/social awareness
• primary industry - exploiting resources from the environment e.g. agriculture, fishing, mining (High energy use)
• secondary industry - Processing raw materials e.g. manufacturing, textiles (high energy use)
• tertiary industry - services e.g. retail, hospitals (medium energy use)
• quaternary industry - research, IT, communication
• How does environmental awareness help reduce energy use?

  • Puts pressure on companies to use paper over plastic packaging
  • energy efficient appliances
  • Double/triple glazing windows
• Energy infrastructure - distribution of energy through cables e.g. cables, national grid, gas and oil pipelines
• the power ratings of domestic electrical appliances is stated in W - this is the amount of power that the appliances use
• Kilowatt-hour (measure of energy demand)

  The amount of energy involved if one kilowatt of power is used for one hour

  e.g. 1 kWh = 1000 J of energy used every second for 3600 seconds

  1 kWh = 3,600,000J
• renewable - Energy resources that are replaced over a timescale useful to humans e.g. solar, wind, tidal, geothermal, hydroelectric
• non renewable - energy resources that are not replaced over a timescale useful to humans e.g. coal, oil, natural gas, nuclear
• Depletable - If more is being exploited/used than being replaced, supplies will diminish e.g. fossil fuels, nuclear
• non depletable - supply will not diminish no matter how much is used e.g. solar, wind, tidal, wave
• abundance - how much there is of that energy resource that is useful e.g. oil, gas
• local constraints - energy resources are not evenly distributed. energy sources are dependent on climate and topography e.g. wind, solar
• intermittency - energy sources are not constant, cannot rely on them and wont always meet demand e.g. solar, tidal, wave
• predictability - you know when its going to happen e.g. fossil fuels
• energy density - the measure of the amount of energy in a given mass of energy resource e.g. nuclear fusion + fission
• Resource availability - can you get to the reserve, is it a high enough grade (COOG) e.g. deep coal reserves, high altitude winds
• need for conversions - the form that the energy is harnessed in may be different to the form that it is delivered to the end user in e.g. burning fossil fuels
• applicability for specific uses - the available energy resources have shaped the way that societies have developed and it can be difficult to change to different energy sources e.g. technological development
• ease of storage - how much can be stored and how easy it us to be stored e.g. fossil fuels such as coal needs lots of space
• ease of transportation - energy resources are rarely found in areas where demand is highest, also affected by form of energy + density e.g. ship, train, pipeline
• environmental impacts - the exploitation all energy resources damages the environment damages the environment in a variety of ways e.g. pollution from extraction
• technological development - all technologies have a period of development before they can be used e.g. nuclear
• political influences - governments may decide to provide assistance to particular sections of the energy industry e.g. legislation
• economical influences - not always easy to calculate the full cost of using energy e.g. changing energy costs
• energy density - a measure of the amount of energy that can be from a given quantity of a resource. Usually expressed as energy content per unit mass but can be expressed per unit volume
• Uses of resources with different energy densities:

  • Straw has a low energy density so long distance transport could use more energy in moving it than it releases when burnt
  • Crude oil has a high energy density, so fuel can power aircraft without being so heavy
  • Uranium has a very high energy density so nuclear power stations do not need the infrastructure for delivering large amounts of energy