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IGCSE Geography - Revision guide: Energy and water resources

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On this page you will find resources on

- Renewable and non-renewable energy sources

- Three Gorges dam - benefits, consequences

- Site selection criteria for Electric, nuclear power stations, wind farms

- Lesotho highlands water project

- Water scarcity causes, impacts

Renewable sources of energy

Renewable energy is the energy which is generated from natural sources i.e. sun, wind, rain, tides and can be generated again and again as and when required. They are available in plenty and by far most the cleanest sources of energy available on this planet.

Pros

  • The sun, wind, geothermal, ocean energy are available in the abundant quantity and free to use.
  • The non-renewable sources of energy that we are using are limited and are bound to expire one day.
  • Renewable sources have low carbon emissions, therefore they are considered as green and environment friendly.
  • Renewable helps in stimulating the economy and creating job opportunities. The money that is used to build these plants can provide jobs to thousands to lakhs of people.

Cons

  • Initial costs are quite steep.
  • Solar energy can be used during the day time and not during night or rainy season.
  • Geothermal energy which can be used to generate electricity has side effects too. It can bring toxic chemicals beneath the earth surface onto the top and can create environmental changes.
  • Hydroelectric provide pure form of energy but building dams across the river which is quite expensive can affect natural flow and affect wildlife.

source : 1

Benefits of Three Gorges project

Three Gorges Dam, China (30°44'18" North, 111°16'27" East), crosses theYangtze River at Sandouping, Yichang, Hubei province, China. The dam’s name refers to the majestic limestone cliffs of the Qutang, Wu, and Xiling gorges, which stretch for about 200 kilometers (124 miles) from Fengjie, in Sichun province, to Yichang, in Hubei province, in China's heartland. The Yangtze is the longest river in Asia and the third longest in the worldsources :1,2

Three Gorges dam

In June 2003, nine years after construction began, the state-owned China Yangtze Three Gorges Development Corporation (CTGPC) filled the reservoir with 445 feet (135 meters) of water, the first of three increments in achieving the eventual depth of 575 feet (175 meters). The result is a narrow lake 410 miles (660 kilometers) long—60 miles (97 kilometers) longer than Lake Superior—and 3,600 feet (1,100 meters) wide, twice the width of the natural river channel.

Wrong climate for damming rivers

Take some time out to watch this interesting video on the 'dam' projects of the world and their impact, narrated by Nigerian environmental activist Nnimmo Bassey

Duration: 12 min 

Siting criteria for Electric Power Plants

Site Requirements 
•  Access
•  Air quality
•  Air space restrictions
•  Buffering
•  Floodplain
•  Fuel delivery
•  Need
•  Site adaptability
•  Site expandability
• Site geography
•  Site size
•  Solid waste management
•  Transmission
•  Water discharge
•  Water supply
 
Community Impacts
·   Aesthetics
•  Archeology-historic sites
•  Community service costs
•  Effects on wells
•  Labor availability
•  Number of relocations
•  Public attitude
 
Public Health & Safety Concerns 
•  Degradation of local air quality
•  Dust
•  EMF
•  Noise
•  Operational odors
•  Traffic safety
•  Water treatment
 
Environmental Impacts 
•  Air quality
•  Groundwater impacts – recharge, discharge, quantity, quality
•  Protected species
•  Stormwater runoff
•  Waste minimization, recycling, reuse
•  Wastewater treatment
•  Wetlands
•  Prime agricultural land
•  Recreational areas
 
Land Use Impacts 
•  Industrial forests
•  Land acquisition
•  Land use compatibility
•  Previous land use
 
Economic Impacts 
•  Delivered costs of energy
•  Future development
•  Jobs and purchases
•  Local tax impact
•  Property values
•  Transmission and distribution changes

Lesotho highlands water project

Lesotho Highlands Water Project (LHWP) is the largest bi-national infrastructure project between Lesotho and South Africa. It involves the construction of an intricate network of tunnels and dams to divert water from the mountains of Lesotho to South Africa. It will provide water for South Africa and money and hydroelectricity for Lesotho. 

Purpose of the Lesotho Highlands Water Project

Lesotho has abundant water resources that exceed requirements for possible future irrigation projects and development.
 

The Objectives of the Project are :

i) To provide revenue to Lesotho by transferring water from the catchment of the Senqu/Orange river in Lesotho to meet the growing demand for water in the RSA's major industrial and population centres

ii) To generate hydro-electric power for Lesotho in conjunction with the water water transfer

iii) To promote the general development of the remote and underdeveloped mountain regions of Lesotho, while ensuring that of Lesotho, while ensuring that comprehensive are taken to counteract any adverse effects which the  Project might have on the local population and their environment

iv) To provide the opportunity to undertake ancillary developments such as the the provision of water for irrigation and potable water supply 

sources: 1,2

Water around the world

'Water for Life Decade ' 2005 - 2015

Water scarcity already affects every continent. Around 1.2 billion people, or almost one-fifth of the world's population, live in areas of physical scarcity, and 500 million people are approaching this situation. Another 1.6 billion people, or almost one quarter of the world's population, face economic water shortage (where countries lack the necessary infrastructure to take water from rivers and aquifers).

Non-renewable sources of energy

Non-Renewable energy is the energy which is taken from the sources that are available on the earth in limited quantity and will vanish fifty-sixty years from now.

Pros

  • Non-renewable sources are cheap and easy to use. You can easily fill up your car tank and power your motor vehicle.
  • You can use small amount of nuclear energy to produce large amount of power.

Cons

  • Non-renewable sources will expire some day and we have to us our endangered resources to create more non-renewable sources of energy.
  • The speed at which such resources are being utilized can have serious environmental changes.

 source : 1

Three Gorges dam project

image source 

Positive Impact

  1.  Since the Yangtze River has a tendency to flood frequently, measures have been taken in the past to lessen the impacts on the area. With the building of the Three Gorges Dam, the flood frequency is increased to one-hundred years, thus lessening the impact floods with have on the economy.
  2. The dam will also provide energy for much of China. Hydroelectric power is a self-sustaining, renewable, clean energy resource
  3. It will aid in boosting agriculture, since the reservoir will hold more water for irrigation. It also will provide the surrounding areas with a stable source of drinking water.
  4. With a final depth of 525 ft, larger ships can be used to transport products up and down the Yangtze River. This increased navigability will increase the economy in the area. Trade is estimated to increase five times in the Central China. Transportation costs are expected to reduce by 35-37%.

Negative Impact

Environmental Impact 

  1. one of the most immediate environmental effects of the Three Gorges Dam has been an increase in landslide activity. This results primarily from erosion caused by the drastic increases and decreases in reservoir water levels, which, when at their peak, create a body of water almost as long as Britain
  2. The submergence of hundreds of factories, mines and waste dumps, and the presence of massive industrial centers upstream are creating a festering bog of effluent, silt, industrial pollutants and rubbish in the reservoir. Erosion of the reservoir and downstream riverbanks is causing landslides, and threatening one of the world’s biggest fisheries in the East China Sea

Social Impact

The most important effect that the construction of the Three Gorges Dam has had on Chinese society has been the displacement of millions of people from the Yangtze river region.

  1. China will lose money due to the inundation of fertile farming land. The 100,000 acres that will be flooded accounts for 10% of the grain supply, 50% of which is rice. The new land is less fertile, and therefore the growing of grain and rice will be harder and more expensive. Instead, value added products, such as citrus fruits, are more viable to grow. However, since these farmers may be unfamiliar with growth citrus fruits or other products, production on these new farms may be slower and yield less economic trade.
  2. The people who are not granted land to farm will be trained to work in cities and towns. The majority of the people living in the reservoir area are uneducated, thus making this transition more difficult.The majority of the people living in the reservoir area are uneducated, thus making this transition more difficult.
  3. A number of cultural and archeological sites will be lost when the reservoir reaches its full depth. These sites are valuable because they are a way to document the nations past. Some sites also hold religious significance. The Chinese government did set aside funds to protect the sites and artifacts that could be saved. However, due to the time constraints and shortage of capable personnel, some of these artifacts may not have been saved or preserved correctly

sources : 1, 2 

A simple dam animation video

Site selection for dams

Factors Affecting the Selection of Site for Dams

1) Good topographical location along the path of river: The best location along the path of the river is river canyon or at the location where there is narrowing of the river. If the aim is to store maximum amount of water, then the volume of basin above dam should be calculated so that sufficient quantity of water can be stored in it. The perfect site is one where there is wide and flat valley.

2) Right geological structure: The rock structure on which the dam will be constructed should be strong enough to sustain the weight of dam and water stored in the dam. The rock structure should be able to sustain all the visible and invisible forces. The rock structure should be stable and there should be least occurrence of the earthquakes in the region. The rock structure should not allow the seepage of water and it should be waterproof.

3) Sufficient water is available: The flow of water where dam is constructed should be sufficient enough to fill the dam. There is lots of loss of water from dam due to evaporation, the flow of river water should be able accommodate this loss of water without affecting the production of electricity from the hydroelectric power plant.

People living around the areas where storage basin is going to be constructed and the areas that will be submerged should be convinced to move from there and they should be given proper compensation and suitable resettlement areas. If this factor is ignored the chances of the success of the hydroelectric power plant will reduced.

Locating Nuclear Power Stations

This slideshow lists the factors for choosing the location of Nuclear power plant in Britain

Wind Farm location factors

Wind Consistency

Wind consistency is probably the biggest factor in choosing where to build a wind farm. It doesn’t matter if the wind blows at 100 MPH if the gust only lasts a second

Ease of Construction

The winds off the coasts are the best wind conditions on earth for power generation. So why are so few wind turbines water bound? It’s a simple matter of economics

Distance to People

There are actually two different considerations here: distance to those who need power and distance from those who will be upset by the noise.

Locating power plants that are long distances from people is generally a bad idea. In order to keep a high-efficiency link with the rest of the power grid, an expensive array of inverters and transformers is needed...

source

Water scarcity

Why is Water So Important?

Learn about the importance of water and how it effects so many aspects of our lives. Click on these links to find out more about...

   
   

 Water scarcity is either the lack of enough water (quantity) or lack of access to safe water (quality).

It's hard for most of us to imagine that clean, safe water is not something that can be taken for granted. But, in the developing world, finding a reliable source of safe water is often time consuming and expensive. This is known as economic scarcity. Water can be found...it simply requires more resources to do it.

In other areas, the lack of water is a more profound problem. There simply isn't enough. That is known as physical scarcity.

source:1,2

Water scarcity - FACT FILE

Did you know that ?

-   Almost one fifth of the world's population (about 1.2 billion people) live in areas where the water is physically scarce. One quarter of the global population also live in developing countries that face water shortages due to a lack of infrastructure to fetch water from rivers and aquifers.

- Water scarcity encourages people to store water in their homes. This can increase the risk of household water contamination and provide breeding grounds for mosquitoes - which are carriers of dengue fever, malaria and other diseases.

FIND more such facts by clicking image below