Renewable source of energy

The sources of energy which are being produced continuously in the nature and never get exhausted which can be produced again and again in short period of time are called Renewable source of energy. For e.g. solar energy, wind energy, hydropower etc.

Non renewable source of energy

The sources of energy which get exhausted after certain period of time, if it used continuously and cannot be replaced quickly are called non renewable source of energy. For e.g. coal, petrol, natural gases etc.

Difference Between Renewable and Non-renewable Source of energy

Renewable	Non renewable
Renewable resources cannot be depleted over time.	Non-renewable resources deplete over time.
Renewable resources include sunlight, water, wind and also geothermal sources such as hot springs and fumaroles.	Non-renewable energy includes fossil fuels such as coal and petroleum.
Most renewable resources have low carbon emissions and low carbon footprint.	Non-renewable energy has a comparatively higher carbon footprint and carbon emissions.
Requires a large land/ offshore area, especially for wind farms and solar farms	Comparatively lower area requirements.
They are non polluting source of energy.	They are polluting source of energy
It is present in unlimited quantity.	It is present in limited quantity.
Life of resources is infinite.	Life of resources is finite.

Sun: The ultimate source of energy

Sun is a huge ball of glowing gases which mainly contain hydrogen and helium. It releases tremendous amount of energy in the form of heat and light which is possible due to thermo-nuclear fusion reaction.

The sun releases about 2.7x10²⁷ J/s. The earth receives only a part of it in average. The earth receives 1.4 KW energy per square meter per minute.

The sun is considered as ultimate or main source of energy because of following reason:

1) All the other sources of energy are outcomes of solar energy.

2) All the animas directly or indirectly depend upon plant, plant trap solar energy to make food by photosynthesis without which life could not be possible.

3) Sun provides heat and light energy for the entire living organism on the earth.

Thermo-nuclear fusion reaction:

The process of fusion of hydrogen nuclei into a helium nucleus at high temperature and pressure is called thermo-nuclear fusion reaction.

Nuclear fusion reaction on sun

The sun has maximum amount of hydrogen at high temperature. Hydrogen splits into proton and electron. Although there is repulsive force between two protons but due to high pressure they fuse to form deuterium (₁H²) and position (₁e⁰).The deuterium fuses with another proton and form tritium .The chain reaction occurs again and another tritium is form. Thus two tritium atoms fuse to form a helium nucleus with the release of large amount of energy.

₁H¹ + ₁H¹à₁H² + 1e⁰ +Energy

₁H²+₁H¹à₁H³

₁H²+₁H²à₂He⁴+Energy

Direct Reaction

4 ₁H¹à₂He⁴+2₁e⁰+Energy

Evidences or condition of nuclear fusion reaction with the sun

1) There is maximum amount of hydrogen in sun.

2) There is very high temperature to split the hydrogen into proton & electron.

3) There is extremely high pressure to fuse two protons.

4) There is plenty of helium formed by the fusion of hydrogen nucleus.

Advantages of solar energy

1) It is renewable source of energy

2) It is free of cost

3) It is pollution free source of energy.

Fossil fuel

The fuel formed by decomposition of dead remains of plants and animals under the earth due to high pressure and temperature are called fossil fuel. For eg: coal mineral oil & natural gas.

Coal & mineral oil are store in limited amount in the nature. If they are used continuously they will exhaust after certain period and cannot be replaced quickly. Therefore they care called non renewable source of energy.

Advantages of fossil fuel

1) They are cheaper and easily available than other fuel.

2) It can be transported easily from one place to another.

3) It is easy to store.

4) They can be used for various purposes like cooking, heating, running vehicles etc.

5) They can be used to generate electricity.

Coal

It is a black material consisting a mixture of compound of hydrogen, oxygen, carbon and free carbons.

Uses of coal

1) It is used of heating & cooling purposes.

2) It is used as fuel in brick factories, iron industries etc.

3) It is used to run railway engines.

4) It is used to generate electricity.

Mineral oil

The liquid fuels like petrol, diesel, kerosene etc. are called mineral oils. They are mixture of compounds containing carbon & hydrogen.

Uses

1) It is uses for heating cooking & lighting purposes.

2) It is used to run vehicle.

3) It is used to generate electricity

4) It is used to manufacture fertilizer, plastics etc.

Natural gas

It is a mixture of methane, butane, propane. The advantages of natural gas are:

1) It burns without smoke.

2) They produce large amount of heat on burning.

3) Liquidified petrol gas (LPG) is used for cooking, running vehicles etc.

Hydroelectricity

The moving water has energy and electricity generated from the energy of morning water in rivers is called hydroelectricity.

Advantages

1) It is renewable source of energy and never gets exhausted.

2) It is pollution free source of energy.

3) Although the production cost is high, it becomes cheaper in long term.

4) It is easy to use and cheap to transmit

5) It is a useful source of energy for running computers and other electronic devices.

Bio-mass

The waste material obtained from plant and animal like cattle dung, human excreta, agricultural wastage are called bio mass or bio fuel.

They can be use directly (dried, dung, firewood) or by producing bio-gas or gobar gas.

Gobar gas is one of the emerging sources of energy in rural Nepal. It is prepared by decomposition of cattle dung & plant waste in absence of air in gobar gas plant.

Advantages

1) It is renewable source of energy

2) It is a clean fuel and doesn’t cause pollution.

3) It is cheaper and easily available in villages.

4) It reduces the cutting down of trees for fire wood.

5) The residue left after producing bio-gas is rich in nutrients and can be used as manure.

Nuclear energy

The energy released from the nucleus of an atom when it undergoes nuclear reaction is called nuclear energy. Nuclear fusion reaction and nuclear fission reaction are the two reactions from where nuclear energy is released.

Advantages of Nuclear Energy:

1) Small amount of nuclear fuel can produce large amount of energy.

2) It is used to generate electricity.

3) Once the nuclear fuel is filled in the reactor it produces energy for log period of time.

Wind energy

The moving air is called wind and the energy posse by wind is called wind energy.

Uses

1) It is used in sailing boat.

2) It is used in pumping underground water.

3) It is used to generate electricity.

Advantage

1) It is a renewable source of energy.

2) It does not cause any pollution.

3) It is available free of cost.

Tidal energy

The energy generated from the tides is called tidal energy. During high tides the water is collected in a reservoir near that sea shore and during low tides water is used to rotate the turbine. The turbine drives the generator and the electricity is generated.

Geo-Thermal energy

The heat energy present inside the earth is called geo-thermal energy.

Advantages:

1) It is renewable sources of energy

2) It is pollution free source of energy

3) It is used in generating electricity.

Disadvantage:

1) Production cost is very high.

2) It needs skilled manpower and new technology.

Present status of energy/fuel in Nepal

In context of Nepal, hydro-electricity & bio-mass are 2 best alternative sources of energy. It is because:

-In Nepal there are large no of rivers from where large amount of electricity can be generated.

-Nepal being an agricultural country. Biomass is easily available.

-Both sources are renewable source of energy.

            Government of Nepal has encourage to use bio-gas or gobar gas because

-It is cheaper & easily available.

-It is renewable & pollution free source of energy.

-It reduces the dependency on fossil fuel and helps to push the energy crisis further.

Bio-gas plant or gobar gas plant are consider as a gift to the farmer as the raw materials required to produce bio-gas is easily available among the farmers. Similarly, the residue left after producing gobar gas is rich in nutrients which can be use manure in the crops.

Scientists are busy in developing solar depending equipment this is because

-It is renewable source of energy and available free of cost.

-It does not cause pollution.

-It reduces the dependency on fossil fuel which helps to reduce the energy crisis.

Due to over growing population and rapid due of non-renewable sources of energy, the world’s a few decades. If that happens human being with have to development of human society. It is therefore energy crisis has become an important issue of the world.

About 80% of the demand of energy in present world is fulfilled by coals, mineral oil and natural gases. The rate of consumption of such energy sources is increasing day by day due to the rapid population growth and industrialization. If the present rate of consumption continues they will finish in few decades. On the other hand if take millions of year to form such energy sources. This indicated that the energy crisis in near future. To avoid this energy crisis the development and use of alternative source of energy is necessary in today’s world.

Alternative sources of energy help to reduce the dependency on non renewable sources of energy. Thus, the fossil fuel are conserved which helps to push the energy crisis further.

According to the data of 2001 studied the present status of energy is as given below.

Mineral oil	35%
Coal	27%
Natural gas	14%
Bio-mass	13%
Hydrostatical energy	5%
Nuclear energy	3%
New renewable energy	3%

Energy crisis

The shortage of non renewable source of energy that is likely to happen in near future due to depletion of fuel is called energy crisis.

Causes

-Rapid population growth and increase living standard of people.

-Rapid use of fossil fuel due to urbanization and industrialization.

-Lack of development & use of alternate source of energy.

Ways of solving energy crisis

By using economically and wisely.

-By conserving present sources of energy.

-By developing and using alternating source of energy.

• The sources of energy which get exhausted after certain period of time, if it used continuously and cannot be replaced quickly are called non renewable source of energy. For e.g. coal, petrol, natural gases etc.
• The sun releases about 2.7x10²⁷ J/s. The earth receives only a part of it in average. The earth receives 1.4 KW energy per square meter per minute.
• The sources of energy which are being produced continuously in the nature and never get exhausted which can be produced again and again in short period of time are called Renewable source of energy. For e.g. solar energy, wind energy, hydropower etc.
• The fuel formed by decomposition of dead remains of plants and animals under the earth due to high pressure and temperature are called fossil fuel.
• Coal is a black material consisting a mixture of compound of hydrogen, oxygen, carbon and free carbons.
• The liquid fuels like petrol, diesel, kerosene etc. are called mineral oils. They are mixture of compounds containing carbon & hydrogen.
• Natural gas t is a mixture of methane, butane, propane. 
• The moving water has energy and electricity generated from the energy of morning water in rivers is called hydroelectricity.
• The waste material obtained from plant and animal like cattle dung, human excreta, agricultural wastage are called bio mass or bio fuel.
• The energy released from the nucleus of an atom when it undergoes nuclear reaction is called nuclear energy.
• The moving air is called wind and the energy posse by wind is called wind energy.
• The energy generated from the tides is called tidal energy.
• The heat energy present inside the earth is called geo-thermal energy.
• The shortage of non renewable source of energy that is likely to happen in near future due to depletion of fuel is called energy crisis.