ENERGY RESOURCES IN THE ENVIRONMENT

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ENERGY RESOURCES IN THE ENVIRONMENT

RESOURCES:

1.  Resources are things we use / need to produce the materials we use in our everyday life.

2.  Energy is the ability to do work.

3. Things that we use / need to produce energy used to do work are called energy resources.

4.  Some of these resources are renewable or non-renewable energy resources.

Renewable energy resources.

5.  These are resources that can be replaces by natural process of reproduction and growth.

6.  Plants and plants are renewable sources.

Examples of Renewable energy resources.

  1. The sun
  2. Water
  3. Plants
  4. Animals
  5. Wind.

Non renewable energy resources.

These are resources that cannot be replaced by any means once they are used.

Examples of non renewable

  1. Fossil fuels
  2. Minerals

Water as an energy resource.

Water can be used as an energy resource in three ways: –

  1. Running water                      
  2. Steam                          
  3. Tidal form

Running water.

1. Water running along rivers can be used to produce (H.E.P) electricity.

2.  Running water helps to move boats and other floating materials along the river.

3.  It is useful in games and entertainment when flying kites.

4.  Plants use the running water as an agent of seed dispersal.

Steam as an energy resource.

1. Steam is a hot gas as a result of water being changed to gas on heating. Steam has kinetic energy that can drive machines.

2. Steam can drive turbines during the production of electricity. Geothermal electricity uses steam after water is heated by underground heat.

3. Steam was used long ago to drive engines of trains called locomotives

4. It was also used to drive engines of steam ships called steamers.

5. At home steam is used to cook food.

Tidal Power as an energy resource.

  1. A tide is a regular rise and fall of the level of the sea.
  2. Tides posses kinetic energy in the moving waves at sea or ocean.
  3. Tides are caused by the attraction between the moon, sun and earth.
  4. The kinetic energy can be tapped using tidal barriers.
  5. At sea, tidal barriers are placed and water is directed through holes which turns turbines and electricity is produced.
  6. Tidal barriers are strong walls built across a tide.

The sun.

  1. The sun is the main source of energy on earth. 
  2. This is because all energy resources directly or indirectly originate from the sun.

The sun as an energy resource.

    The heat from the sun is used for:-

  1. Drying clothes.
  2. Preserving food during direct sun drying of food, using solar driers.
  3. It can be tapped using a solar cooker and its used for cooking.
  4. It is used for evaporating water from water bodies  such as lakes and from plants which forms clouds and rainfall is got.
  5. It is used for animals and people warming themselves.
  6. Energy from the sun is changed into solar electricity by the solar panels. This is used for lighting at night, operating radios, TV, etc
  7. Plants use solar energy to manufacture their own food during the process of photosynthesis.

Minerals as energy resources.

  1. Uranium is the commonest mineral used as an energy resource.
  2. It is a grey metal used as a source of nuclear energy.
  3. Heat from uranium is used to boil water to produce steam that produces electricity.
  4. Uranium is also used in the production of bombs. (nuclear bombs)

Fossils as energy resources.

Fossils are remains of plants and animal of long ago buried between rocks underground.

Examples of fossils

  1. Petroleum or crude oil
  2. Natural gas and
  3. Coal

Petroleum or crude oil.

  1. Petroleum is a thick dark brown or black sticky liquid. It is mined by boring holes through the ground to the oil well underground.
  2. It is them taken for refining at the oil refinery.

Products of petroleum

  1. Diesel
  2. Petrol,
  3. Paraffin,
  4. Aviation fuel, fuel,
  5. Plastic and nylon.
  • Diesel, petrol, paraffin and aviation fuel are resources used to produce heat and light when burnt.
  • Fuels from petroleum are used in running machines, heating and, cooking food.
  • They are also burnt to provide light.

Natural  gas.

  1. During the formation of petroleum or coal, a gas is formed above them.
  2. This gas can be tapped after drilling.
  3. It is then put under a lot of pressure and is liquefied.
  4. It is stored in cylinders.
  5. It is used for lighting, cooking, heating and refrigeration.

Coal

Coal is another fossil which used as an energy resource.

  1. Coal is a hard black material found underground.
  2. It burns with a lot of heat.
  3. When burnt, coal can be used in warming houses in cold regions.
  4. It is used in industries to provide heat that smelts metals
  5. Coal is also used to heat water to steam during the generation of thermal electricity.

Conserving fossil fuels.

Fossils are non-renewable resources. They can get exhausted if not sustainably used and cannot be replaced.

They can sustainably be used by;

  • using less fuel consuming
  • using alternative sources of energy like H.E.P instead.

Plants as energy resources.

Plants are sources of energy when used as;

  1. Plant fuel such as firewood, charcoal, briquettes, and husks.
  2. Food.
  3. Bio-gas.

Plant fuel as source of energy.

A fuel is anything that can burn to produce heat and light.

Wood can be used as a fuel in the following ways:

  1. When fire wood is burnt, it produces heat and light. This heat is used for cooking and lighting.
  2. Charcoal which is a product of wood burnt in limited oxygen, can also be burnt to produce heat.
  3.  Briquettes are products that are made by pressing saw dust or other plant residues like coffee husks or rice husks. These can also be used as fuel.
  4. Saw dust can also be burnt to produce heat and light.
  5. Other plants remains such as coffee husks, rice husks can also be burnt to produce energy.

Food as a source of energy

  1. Green plants make their own food from water and carbon dioxide by the help of sunlight.
  2. This food is stored by the plants in form of chemical energy..
  3. People harvest these plants and use them as food.
  4. During the process of respiration, food from plants is used to provide energy to people and animals to do different types of work.

Bio-gas as an energy  resource.

  1. Biogas is a gaseous fuel that can be got from fermenting animal and plant wastes.
  2. If the wastes are allowed to ferment, they form a gas that can be collected and then later burnt to produce heat and light.
  3. This gas mainly contain methane gas.

Diagram of a bio-gas digester.

bio digester
  • Fermented molasses from sugar cane can also be distilled into ethanol alcohol.
  • This can be burnt to produce heat and light. It can also be mixed with little petrol to run car engines.

Conserving energy from plants.

Wood from plants can be sustainably be used by:-

  1. Using sustainable harvesting methods i.e. copping, lopping and selective felling.
  2. Planting other trees after cutting which take less time to mature.
  3. Use of fuel saving cooking materials.

These includes: –       

a).    fuel saving stoves or fire places

        b).    pressure cookers

        c).    heat conserving cooking materials like pots

  1. Using fuel conserving methods of cooking i.e.

a).    covering food when cooking

b).    cooking more than one items at ago.

c).    soaking dry foods first before cooking ie beans

  • Using alternative sources of fuel instead of wood fuel ie bio-gas, electricity, natural gas etc.

Animals as an energy resources.

Animals obtain their energy from eating plants. Even carnovorous animals in one way depend on plants since they feed on animals that eat  plants.

This results into a food chain or food web.

FOOD  CHAIN

food chain

In a food chain, plants are producers, animals are consumers and bacteria are decomposers.

A FOOD WEB

food web

 Energy from animals can be used in the following forms:-

  1. when the animals are eaten as food.
  2. When the animals perform tasks to people .Tasks performed by animals are ploughing, pulling carts, transporting people.
  3. When their wastes are used to produce bio-gas.

Conserving animals.

  1. Use scientific methods to bread fast maturing and producing animals to ensure constant and adequate supply of animals for food.
  2. Gazette places asNational Parks and Game Reserves to protect the animals.

Energy resource from wind and air.

Wind is moving air. Air in form of oxygen is used in respiration to produce energy. Wind can be used to provide energy for the following purposes.

  1. drying clothes
  2. wind is used in winnowing seeds.
  3. Wind helps to move boats on water.
  4. It is used in games to fly kites, gliding etc
  5. Wind helps to run wind milk which can be used to generate electricity, pump water, grind grains etc.