Natural and energy resources: Solar Energy

A natural resource may be defined as any material given to us by nature which can be transformed in a  way that it becomes more valuable and useful. It is generally defined as all those things given by nature on, above and under the surface of the earth.

Solar energy:

1. It is renewable energy 
2. Sun heat is directly utilized for water heating, room heating, vaporization ext.
3. Indian's first solar park in Gujarat was inaugurated on 29th Dec 2019.
4. The national solar mission (NSM) is major initiative of the government of India and state governments to promote ecologically sustainable growth while addressing Indian's energy security challenge.
5. The target is to achieve 100 GW by 2022.
6. Kamuthi solar power project is the largest single location solar power plant in the world, located in kamuthi in Tamil Nadu.
7. This solar plant is the the world's second largest solar park with a capacity of 648 MW.
8. Launched mobile app ARUN ( Atal Rooftop solar user Navigator) for ease of access of beneficiary's
9. for request sub mission and awareness. 

Advantages of solar energy

• It is clean, available in plenty and uninterrupted.
• The solar energy devices can be installed even in remote villages and now are even getting inexpensive with the advancement in technology and increased competition.

Limitations

• The limitations with solar energy is that it can't be sued in the temperate regions, also consumes land and can't be used to run heavy machines.
• The target for India has been set under national solar mission, around 100 GW including both rooftops and large and medium scale grid installations.

Uses

• Direct solar can be used as heat, light, and electricity through the use of solar cells.
• Direct use of solar energy can be used through various devices like: Three types of systems a) passive b) active c) photovoltaic     

a) Passive solar energy 

Some of the earliest uses of solar energy were passive in nature such as to evaporate sea water for producing salt and to dry food and clothes.

b) Active use of solar energy 

• Active solar heating and cooling systems rely on solar collectors which are usually mounted on roofs.
• Such systems also require pumps and motors to move the fluids or below air by fan in order to deliver the captured heat.
• The main application of these systems is to provide hot water, primarily for domestic use.

c) Solar cells or photovoltaic technology 

• Solar energy can be converted directly into  electrical energy by photovoltaic cells.
• Photovoltaic cells are made of silicon and other materials added as an impurity. When sunlight strikes the silicon atoms, the electrons are ejected. This principle is called as " photoelectric effect".
• A typical solar cells is generally a transparent wafer that contains a very thin semiconductor.
• Sunlight energizes and causes electrons in the semiconductor to flow. This flow creates an electrical current.