GEOGRAPHY O LEVEL(FORM TWO) NOTES SUSTAINABLE USE OF POWER AND ENERGY RESOURCES

SUSTAINABLE USE OF POWER AND ENERGY RESOURCES

Energy

Energy is defined as the power required to carry out an activity. It is one of the most important resources in the world. To do work, one needs energy or power.

Power

Power is the rate of doing work. It is equivalent to the amount of energy per unit time. Therefore, energy produces power, and power is used to carry out activities.

Energy uses

1. Used in running machines in industrial, agricultural, and transport sectors.
2. Used in cooking, warming bodies, lighting, etc.
3. Facilitates photosynthesis in plants.

A. MAJOR SOURCES OF POWER

Energy resources are classified as renewable and non-renewable resources.

Non-renewable energy resources

Also known as exhaustible resources, these cannot be replaced once used up. Examples include:

• Coal
• Petroleum
• Natural gas
• Fuel wood
• Nuclear resources

Renewable energy or power resources

These resources can be replaced after use. They are inexhaustible and sustainable. Examples include:

• Hydroelectric power
• Tidal energy
• Solar energy
• Wind
• Geothermal power
• Biogas/biomass

Inexhaustible energy resources are those that can never be depleted through use. Examples are:

• Solar energy
• Wind energy

Human beings cannot exhaust or deplete these resources.

B. METHODS OF EXTRACTING POWER AND ENERGY

(i) Non-renewable energy sources

Coal

• Coal is a black or brown rock consisting mainly of carbon.
• It supplies energy when burnt.
• It is used in various ways worldwide.
• Countries mining coal include:

• USA
• China
• Russia
• Zimbabwe
• South Africa
• Nigeria

• Uses include generating electricity, heating, cooking, and producing gas, cosmetics, adhesives, fertilizers, dyes, perfumes, and synthetic fibers.

Advantages

1. Promotes industrial development, especially in iron and steel industries.
2. Creates employment opportunities.
3. Stimulates transport development through manufacturing locomotives and ships.
4. Facilitates domestic activities like cooking and warming.
5. Used in producing other energy sources like oil and gas; South Africa uses coal to produce oil.

Disadvantages

1. Non-renewable; once exhausted, it cannot be replaced.
2. Causes air pollution by emitting carbon dioxide (leading to global warming) and sulfur dioxide (leading to acid rain).
3. Mining causes land degradation and landscape destruction.
4. Heavy and bulky, causing transport problems.
5. Requires significant capital for exploitation, potentially leading to decline in other sectors.
6. Oil spills are dangerous to ecosystems.
7. Risk of accidents due to fire outbreaks and explosions.

Demand for coal has been declining due to:

1. Low calorific value.
2. It is dirty.
3. High production costs due to reopening mines.
4. Transport difficulties because of bulkiness and weight.
5. Competition from more efficient and environmentally friendly energy sources.

Oil

• Non-renewable source formed underground from decaying plants and animals.
• Main producers include:

• Middle East
• USA
• Russia
• Mexico
• China
• UK

Uses include:

• Generating electricity
• Fuel energy
• Producing petroleum gas
• Cooking
• Making fertilizers
• Medicine and plastics

Natural gas

• Non-renewable resource formed underground from decaying animal and plant material.
• Main producers include:

• USA
• Canada
• Russia
• Mexico
• Venezuela
• Algeria
• China

• Tanzania has discovered natural gas deposits at Songosongo.
• Used for cooking, heating, and electricity production.

Advantages of natural gas

1. Efficient.
2. Cleanest fossil fuel, least polluting.
3. Easy to transport.

Disadvantages

1. Explosive, causing destruction and death.
2. Causes some air pollution.
3. Exhaustible (non-renewable).
4. Oil, coal, and gas are referred to as thermal energy sources.

Nuclear energy

• Non-renewable source.
• Produced by reactions of nuclei of radioactive metals like uranium.
• Countries with nuclear power stations include Britain (about 35), USA (about 80), France (about 36), former USSR (about 43), Japan (about 28), Germany, Canada, Sweden, Belgium.

• Coal is used for producing heat for electricity and making nuclear bombs.

Advantages of nuclear energy

1. Clean, producing fewer greenhouse gases.
2. Efficient in use.
3. Economical, using small amounts of raw materials and producing little waste.

Disadvantages

1. Radiation is dangerous, e.g., Chernobyl leakage in Russia caused cancer.
2. Building nuclear plants is very expensive.
3. Waste disposal is problematic due to radioactivity.
4. Has increased terrorism risks, such as bombings of American embassies in Kenya and Tanzania.

Fuel wood

• Non-renewable fossil fuel.
• Provided by trees.
• Mainly produced in less economically developed countries (LDCs) in Africa and Asia.
• Can be converted to charcoal by heating under limited oxygen supply.
• Used for cooking and heating.

Advantages

1. Easily available.
2. Inexpensive and largely obtained freely from forests.
3. Replacement possible by planting new trees.

Disadvantages

1. Not efficient and time-consuming.
2. Collection leads to deforestation, causing soil erosion and desertification.
3. Non-renewable as replanting cannot keep pace with consumption.
4. Contributes to environmental pollution.

The use of fuel wood in Tanzania

People in Tanzania will continue using wood for many years due to:

1. Poverty.
2. High expenses associated with other sources.
3. Unreliable supply of other sources.
4. Lack of strict policies controlling fuel wood use.
5. High population growth.
6. Some tribes believe food cooked with fuel wood tastes better.
7. Poor knowledge and skills in using other energy sources, especially in rural areas.
8. Lack of awareness of environmental impacts of fuel wood use.

Ways Tanzania can reduce or avoid the use of fuel wood

Methods include:

1. Encouraging use of alternative energy sources like solar, hydroelectric, natural gas, and kerosene, with affordable prices.
2. Educating people on economical energy use, such as modern stoves that use less fuel wood.
3. Encouraging tree planting to counter wood shortages.
4. Formulating policies restricting excessive firewood extraction.
5. Encouraging population control to reduce energy demand.

(ii) Renewable resources

Hydroelectric power

• Requires a regular water supply to drive turbines.
• Producing countries include:

• Canada
• Norway
• Tanzania
• Russia
• Brazil
• China

Used for electricity production, lighting, and heating.

Advantages

1. Very clean and environmentally friendly.
2. Reservoirs/dams help control floods and provide water during shortages.
3. Often located in remote mountainous areas with low population.
4. Stimulates industrial development; South Korea has benefited greatly.
5. Improves communication systems like internet, radio, TV, and satellites.

Disadvantages

1. Dam construction floods large areas and displaces people, e.g., Akosombo dam in Ghana.
2. Lack of rainfall and dam silting affect power generation.
3. Pylons cause visual pollution.
4. Dams can lead to disease outbreaks.

Hydroelectric schemes in Africa include:

• Kidatu
• Mtera
• Stiegler’s Gorge
• Kihansi in Tanzania
• Orange River Project
• Nkula Falls in Malawi

Tidal power source

• Renewable source; power produced when tidal water drives turbines along the coast.

Main producers:

• France
• USSR
• China
• Canada

Used to produce electricity.

Advantages

1. Clean and does not pollute the environment.
2. Barrages protect coasts from erosion.
3. Large schemes produce significant electricity.
4. Encourages fishing and tourism industries.

Disadvantages

1. Expensive to construct.
2. Few suitable sites; must be coastal, disadvantaging inland areas.
3. Can damage coastal areas and disrupt shipping.

Solar energy

• Renewable energy from the sun.
• Used for direct heating, drying clothes and crops, and electricity production.
• Potential areas are tropical regions with abundant sunshine.
• Examples include:

• USA
• India
• Kenya (Kibwezi and Ikutha Health centers in Machakos and Kitui districts) and parts of Tanzania

Advantages of solar energy

1. Usable in many parts of the world.
2. Renewable and unlimited supply.
3. Non-pollutant, clean, and efficient.
4. Easy to install in new buildings.
5. Promotes tourism in sunny countries.
6. Provides vitamin D, essential for strong bones; deficiency causes rickets.
7. Facilitates rainfall formation through evaporation.

Disadvantages of solar energy

1. Expensive to install; requires high capital for equipment.
2. Supply stops during cloudy weather or at night, causing energy shortages.
3. Produces less energy compared to hydroelectric power.

Wind energy

• Energy produced by moving air masses.
• Renewable source as it does not get exhausted.
• Used for generating electricity and pumping water from underground.
• Important for pollination, rainfall distribution, temperature regulation, and evaporation.
• Used in areas such as:

• Denmark
• California
• UK (with many forms of wind)

• In Tanzania, turbines are installed in Singida and Dodoma for water pumping.
• A group of turbines in one place is called a wind farm.

Advantages of wind energy

1. Very clean energy.
2. Non-pollutant to air.
3. Cheap to harness and operate.
4. Suitable for small and large scale schemes.
5. Used to produce electricity by driving turbines.

Disadvantages of wind energy

1. Winds are unpredictable and intermittent; energy production stops when wind stops.
2. Causes visual and noise pollution in quiet areas.
3. Many turbines needed for large energy production, increasing costs.

Geothermal power

• Renewable energy source.
• Heat energy generated from the earth’s interior.
• Produced through volcanic activity like geysers and hot springs.
• Examples of geothermal areas:

• Kenya
• Japan
• Russia
• New Zealand

Advantages of geothermal power

1. Used for electricity generation and direct heating.
2. Many potential areas, especially volcanic regions.
3. Attracts tourists and earns foreign exchange.
4. Supports development of communication networks needing electricity.
5. Used for heating in cold areas during winter.

Disadvantages of geothermal power

1. Water from the ground can release sulfuric gases causing acid rain if tapped improperly.
2. Geothermal plants are expensive to develop.
3. High temperatures can cause maintenance issues by melting metallic parts.
4. Plants are built in geologically weak areas like rift valleys, risking energy supply interruptions.

Factors limiting geothermal power development in Tanzania

1. Low capital investment.
2. Presence of other energy sources like hydroelectric, fuel wood, wind, and oil.
3. Costly exploration of potential areas.
4. Low market demand due to poverty and rural economy.
5. Low affordability of supply charges.
6. Low technology levels among the population.

C. THE IMPORTANCE AND USES OF POWER AND ENERGY

Power and energy resources are important in:

• Industry: Used to run machines, provide light, electricity, and heat for processes like welding, promoting industrial and economic development.
• Agriculture: Powers heavy machinery for ploughing and harvesting, mostly running on diesel, supporting agricultural growth.
• Transportation: Fuels motorcycles, vehicles, airplanes, trains, and ships, facilitating movement of people and goods.
• Mining: Powers machines and lighting for mining activities.

They also provide employment, foreign exchange, government revenue, improve transport and communication infrastructure, and promote trade and industries.

D. PROBLEMS FACING POWER AND ENERGY PRODUCTION

1. Changing climatic conditions: Droughts and reduced rainfall lower water levels at hydroelectric stations.
2. Lack of capital: High costs limit developing countries from setting up energy facilities.
3. Lack of varied energy resources: Some countries lack geothermal steam, uranium, and other sources.
4. Poor technology and skilled personnel: Developing countries often use outdated, inefficient technology.
5. Environmental pollution: Energy production causes pollution through spills and nuclear accidents.

E. Ways to address problems of power and energy production

1. Regular dredging to maintain dam capacity.
2. Diversify energy production to reduce effects of price and climate changes.
3. Adopt technological advancements for efficient energy production.
4. Research to improve production methods and reduce pollution.
5. Establish institutions to train energy professionals.
6. Partner to raise capital for energy facilities.

F. FOCAL STUDIES

Solar and Wind power in the USA

The USA is technologically advanced with high energy demand for industries and population.

Solar power contributes a small percentage of total energy, mainly in sunny areas like California and Nevada. The government and organizations promote solar energy investment.

Wind power is more widely used, generating about 0.7% of electricity. Texas is the largest producer, followed by California, using windmills.

Importance of solar and wind power in the USA

1. Source of employment.
2. Industrial development.
3. Agricultural support.
4. Conservation of non-renewable resources.
5. Reduced environmental pollution.

Problems facing solar and wind power in the USA

1. Dependence on weather; low sunshine or wind reduces electricity generation.
2. Reluctance to shift from traditional sources like hydropower.
3. High equipment costs limit large-scale investment.

Biogas

• Renewable energy derived from decay of plant and animal (including human) waste.
• Produces gases like ethanol and methane from fermentation.
• Used for:

• Heating
• Lighting
• Generating electricity

Main producers of biogas

• Brazil
• Japan
• China
• Germany
• Denmark
• India
• Tanzania
• Kenya

Advantages of biogas

1. Cheaply produced and widely used.
2. Affordable in developing countries.
3. Requires intermediate technology.
4. Usable at local level.
5. Helps waste management by recycling and pollution control.
6. Digestate used as fertilizer to boost crop production.
7. Improves living standards by providing cheap energy.
8. Gas can be exported, earning foreign currency.

Disadvantages of biogas

1. Requires careful handling; careless use can cause destruction after burning.
2. Needs large, regular supply of suitable waste, which can be cumbersome.
3. Expensive to set up; digesters require capital.
4. Methane emissions contribute to air pollution.
5. Some wastes used as fertilizer can cause water pollution and disease spread.

Biogas in Tanzania

Factors influencing biogas development in Tanzania

1. Need to reduce costs of other energy sources.
2. Reduce dependence on fuel wood in rural areas.
3. Abundant plant and animal waste supply.
4. Improve rural living standards.
5. Government and international support, e.g., Ministry of Water, Energy and Minerals, Khadi and Village Industries Commission of India, missionaries.

Major constraints to widespread biogas use in Tanzania

1. Shortage of building materials for digesters.
2. Transportation problems for materials and raw inputs.
3. High cost of digesters, unaffordable for many locals.
4. Resistance to new technology due to traditional fuel wood use and low technology levels.
5. Siltation reducing dam water volume, lowering electricity generation.

G. Solutions to problems facing power production

1. Frequent dredging of reservoirs to prevent siltation.
2. Develop alternative power sources.
3. Establish training institutions for skilled personnel.
4. Liberalize power generation to increase funding for biogas and hydroelectric power.
5. Government and organizations should aggressively market biogas production and use.

H. Lessons for Tanzania from the USA

1. Diversify energy sources to reduce risks from reduced production of any one source.
2. Government should create departments to promote alternative energy sources like solar and wind.
3. Government support through funding and policy formulation is essential for energy development.