3.5 Energy and Water Resources

syllabus_link_buttonDescribe the significance of fuelwood in LEDCs and of non-renewable fossil fuels in terms of their availability in certain areas and in terms of the contribution made by coal, oil, natural gas and wood in supplying vast amounts of energy.

Fuelwood

Developing countries rely heavily on wood as a source of fuel, especially in the rural areas.  The primary adfuel woodvantage of wood is that it can be collected for free or a little money, it is easy to collect and relatively easy to transport.  Wood can be burnt easily, releases a significant amount of heat, can be made into charcoal and is easy to store.

Many rural areas in developing countries do not have mains electricity so use wood for their cooking and heating.  If managed correctly, wood will regenerate and can become a sustainable source of energy.

Unfortunately in many developing countries the increasing population has led to unsustainable collection of wood.  Deforestation has occurred, people have to walk further to collect wood and increased pressure is put on remaining wood supplies.

 

Fossil Fuels

coal

Fossil fuels are used to generate electricity in many LEDCs.   Coal is relatively abundant, often easy to get to if it is in rock layers close to surface and it burns easily.  The technology for using coal is established aswell as being relatively quick and cheap to build.  NICs such as China and India need plentifull energy for their rapidly expanding industries and fossil fuels are generally the most economical.

Burning fossil fuels is a significant contributor to the greenhouse effect, and coal is the worst of the fossil fuels for this.  There is increasing global concern about the use of fossil fuels and a desire to use more renewable sources but the cost of these is prohibitive for many developing countries.

 

syllabus_link_buttonDescribe the growing significance of renewable energy supplies (geothermal, wind, running water, solar, biofuels) to reduce dependence upon fossil fuels, to alleviate the world’s energy crisis, and to offer opportunities for the development of alternative energy sources.

 

Renewable Energy Supplies

The rising price of fossil fuels and increasing concern about atmospheric pollution and international agreements on  carbon emission levels are leading to rapid growth in the use of renewable energies.

Solar Power

Solar power can be used to either heat water or to generate electricity.  Small scale water heating pannels are common throughout Spain and reduce household consumption of electricity.

Ikea malaga solar pannels
solar panels: Ikea, Malaga, Spain

 

Photovoltaic cells generate electricity from sunlight but are more expensive to install.  Government subsidies have vastly increased the number of households with these on their roof. Ikea in Malaga, Spain has covered its car park in these panels to provide its electricity.

Large scale solar plants with arrays of mirrors that concentrate the sunlight onto a central unit are also increasingly being built.  Seville in Spain has a large solar plant that has the ability to store the energy for a limited time and supply it after dark when the demand is higher.

Solar power has huge potential in countries with sunny climates but the cost is still much higher than using traditional fossil fuels.

 

Wind Power

Wind farms are being invested in by many European countries.  Initial set up costs are high and there has been opposition to them in many places due to the impwindact on the scenery, noise pollution and danger to birds.  Concerns about the unreliability of the wind in many locations exist.

Large offshore wind farms are being developed and larger windmills are increasing efficiency.

Spain, Nicaragua and the UK are examples of countries that have large windfarm developments.

 

Hydro-Electric Power (HEP)

Electricity generated by released water spinning turbines. This requires fast flowing water or high water pressure (dams).

A very clean form of energy (after the initial building of the dam).

HEP

Many of the most suitable rivers have already been used to harness HEP. New projects are larger in scale and the turbines are more efficient.

HEP dams destroy large areas of vegetation & can cause environmental problems downstream due to changes in river flow.

The 3 Gorges Dam in China is perhaps the most famous example.  The worlds largest dam is designed for power generation, flood control and navigation of the river.

 

Geothermal Power

Using the heat of the earth to generate power.

geothermalIt is commonly used as a source of heating for buildings through pipes that heat water underground & then run through houses.

In some places it is used to generate electricity by using the steam to turn turbines. Indonesia & the U.S.A use geothermal power sources.

It is very expensive to set up but then requires no additional fuel once established.



 

syllabus_link_buttonDescribe the uses made of water for agriculture, domestic and industrial demand. Candidates should also recognise that in certain areas there are water shortages which impact upon the local people and the potential for development. This leads to competition for the use of the available water resources and requires careful management.

Demand for Water

Agriculture is a major user of water. The increased demand for food has led to more intense methods of farming that require extensive irrigation to grow crops in arid regions. The Colorado river supplies vast areas of arid land with water to produce huge quantities of food for the United States.

Many industries use substantial amount of water in the production of goods. Improvements in efficiency and recycling techniques are enabling industries to reduce the quantities that they consume. Industries that require large quantities of water often locate in regions where the supply of water is sufficient.

Domestic water consumption relates to household water use. Households in developed countries tend to have higher consumption per person.

Water Scarcity and Management

Many regions of the world are experiencing increasing water shortages (scarcity). This is mainly due to rising population levels and the need to produce more food. Climate change is also affecting rainfall patterns.

Many large scale dams have been built and are planned to try and meet the increasing demands for fresh water but these alone will not solve the problem. Desalinisation of sea water is being increasingly used but the cost is still too high for many developing countries. Decreasing the demand for water through more efficient use of it in industry and households should play a vital part in reaching sustainable levels of use.

The Colorado River, USA

The Colorado river is one of the most managed water systems on the planet. It has over 20 dams along its 2000km length which store water for irrigation, supply water for desert cities and produce electricity. Las Vegas, Phoenix and Tuscon rely on the Colorado. Despite vast quantities flowing through the Colorado so much is extracted for human uses that it barely flows in some sections. careful future management of the river and

The Nile

The River Nile is one of the major river s of the world. Flowing through 9 countries and passing through deserts regions before it reaches the Mediterranean Sea it is highly valued. Rapid population increase, the need for more electricity and a desire to use more water for irrigation in many of the countries has led to international tension over extracting water. Ethiopia and Uganda (the sources of the Nile) are keen to build large dams to store and use some of the water for irrigation and energy. Egypt is against them taking more water from the Nile since it is the supplier of virtually all their freshwater.

 

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Question 1 of 3

Practice Questions

  1. What is meant by non-renewable resources? [2 marks]
  2. Give 2 examples of fossil fuels? [2 marks]
  3. Describe the importance of fuelwood in developing countries. [4 marks]
  4. Describe the costs and benefits of a renewable energy resource. [4 marks]
  5. With reference to a named example, describe the competing demands for water. [7 marks]