25 - Energy

• Water transfer


  Moving water from areas of surplus to areas of deficit
• Water transfer in the UK

  • Water is moved from the mountains of mid-Wales with heavy rainfall to supply the large urban populations of the West Midlands
  • Water is diverted from the River Severn near Gloucester and moved by canal to supply the city of Bristol with half its water
• Large-scale water transfer schemes

  • Tagus-Segura transfer project in Spain
  • Murray-Darling scheme in Australia
  • Colorado scheme in the USA
  • South-North scheme in China
• Water transfer schemes may help relieve water shortages in one area but they do pose challenges
• Diverting water


  Diverting surface water to underground storage areas such as aquifers to prevent evaporation and enable the water to be used when less is available
• Building dams and reservoirs

  Collecting rainwater by building more and larger reservoirs to create artificial lakes from which water can be released during drier periods
• Disadvantages of building dams and reservoirs

  • Economic costs - dams are very expensive to build
  • Social costs - large-scale construction causes disruption and displacement of people
  • Environmental costs - ecosystems are destroyed by flooding
  • Physical costs - huge losses of water through evaporation from the reservoir surface
• Desalination


  The removal of salt and other minerals from seawater to produce freshwater suitable for human consumption and irrigation
• Desalination has been costly but the situation is changing as water prices rise and technology becomes cheaper</b>
• Disadvantages of desalination include the vast amounts of energy needed and the environmental impacts of the salt deposited back into the sea
• South-North Water Transfer Project (SNWTP)

  A scheme in China to move huge quantities of water from the humid south to the arid north
• The SNWTP was needed due to the mismatch between water availability and water demand in China, with the North China Plain having a huge water demand but shortage of rainfall
• The SNWTP


  1. Eastern route completed in 2013 to provide water for Tianjin and Weihai

  2. Central route opened in 2014 to provide water for 20 large cities including Beijing

  3. Western route planned but controversial and put on hold
• Advantages of the SNWTP

  • Provides a reliable water supply in the water deficient north
  • Improves availability of safe water and reduces health risks
  • Provides water for industrial growth
  • Provides water for irrigation and increased food production
• Disadvantages of the SNWTP


  • Displacement of large numbers of people
  • Wildlife and ecosystems badly affected
  • Loss of historical sites
  • High cost paid for by taxes
  • Danger of droughts in the south
  • Water losses through evaporation from open canals
  • Risk of damage from earthquakes
• The SNWTP is increasingly being recognised as needing alternatives that are cheaper and more environmentally friendly
• Sustainable water supply


  Achieving a balance between water consumption and water supply, and maintaining this balance in the long term as water demand rises
• Energy security


  Energy is available for all at an affordable price
• Energy insecurity


  Energy is not available for all at an affordable price
• Nearly 90% of the world's energy supply comes from three non-renewable fossil fuels: oil, natural gas and coal
• The other renewables category is made up of geothermal, wind and solar energy, biofuels, biomass and waste
• The world's major consumers of energy


  Are also the major producers of energy, mainly high-income countries (HICs)
• Energy production is low


  In countries where the demand for energy is also low, mainly low-income countries (LICs)
• Energy gap


  The use of fossil fuels is being phased out but the resulting loss of energy is greater than the amount of energy being produced from alternative renewable sources, leading to energy balances increasingly in deficit
• Energy insecurity is increasing, particularly when there is more reliance on imported supplies of energy
• Low-income countries (LICs) mostly have energy insecurity
• Parts of the world with the lowest risk of energy insecurity

  • Canada
  • Russia
  • Most Middle Eastern countries
  • Indonesia
  • Australia
• High-risk countries for energy insecurity

  • Africa
  • Parts of Asia
  • Parts of Latin America
• Some high-risk countries have small energy demands so don't need to import large quantities
• Energy gap


  An increasing number of countries face an energy gap where the loss of energy from phasing out fossil fuels is greater than the amount of energy being produced from alternative renewable sources
• In the UK and elsewhere, the energy gap is becoming wider
• Energy insecurity


  • Low
  • Medium
  • High
  • No data
• Global energy consumption has nearly tripled over the last 50 years
• Economic development


  Increases energy consumption, particularly advances in agriculture, industry and transport
• Population growth


  Increases energy consumption as each person consumes energy directly and increases demand for food and transport
• Modern technology


  Increases access to various forms of energy, particularly electricity, and helps lower energy costs
• Geology


  Determines whether a country contains fossil fuel deposits and whether they can be easily extracted and exploited economically
• Climate


  Affects the potential for renewable energy generation from hydroelectric power, photovoltaic cells and wind turbines
• Environmental conditions


  Affect the accessibility and costs of energy sources, e.g. harsh climates and difficult terrain
• Low production costs


  Relatively cheap energy supply