Difference between Solar Energy and Wind Energy

Solar energy and wind energy both are renewable energies as they are obtained from renewable sources of energy, sun and wind respectively. Although both are same type of energies and are produced in a clean and efficient way, they differ from each other as described below.

Solar energy

Sun is the main source of energy on earth. The energy received from the sun is called solar energy. Only 47% of the energy radiated from the sun reaches the earth. According to estimates, our country receives 5,000,000 crore kilowatts of solar energy per year. Solar energy is clean and pollution-free energy. Solar energy is used in drying clothes, drying vegetables, fruits, making salt from seawater, reducing the moisture of crops after harvesting, and more.

Uses of solar energy:

i) Direct use:

• Direct use of solar energy is collecting solar energy in the form of heat. Solar cookers are used to collect solar energy in heat form.
• Another direct use is converting solar energy into electrical energy. It involves the use of solar cells.

ii) Indirect use:

• Wind, which is used to produce wind energy, blows when the air is heated unevenly by the sun's rays.
• The ocean waves are also caused by the sun's rays. The energy of ocean waves is also used for various purposes.
• The existence of rivers is also due to the water cycle, which depends on the sun. The energy of water in rivers can be converted into electrical energy. Thus the energy stored in the dam is also due to the sun.
• Trees and plants use solar energy in the process of photosynthesis. So, the heat obtained by using wood is also indirectly dependent on the sun.

Types of solar energy systems

i) Grid-tied:

This system is a low-priced system and also gives quick payback on investment. This system is beneficial for anyone who is trying to save money on their power costs.

ii) Off-Grid system:

This system uses solar panels to charge the batteries. This system is a high-priced system because the batteries system is very costly. This system is perfect for the distant area or backwoods area and unbuilt area.

iii) Grid-tied with battery backup:

This system is perfect for uncertain power and emergency situation. If any power failure occurs or for emergency usages, battery backup is provided in this system. It is a costly system and also payback less on investment.

What is a solar collector?

The solar collector is a device used to collect solar radiation on its surface or used to absorb solar radiation. The surface of the solar collector is designed in such a way that it absorbs maximum solar radiation.

Solar collectors are divided into two types:

1. Non concentrating collector
2. Concentrating collector

1. Non concentrating collector:

There are two types of Non-concentrating collectors.

1. i) Flat plate collector: It has one absorber plate, which receives solar radiation through a transparent glass cover. It has a copper tube connected to the absorber plate. The collector has a thermal insulator all around, which prevents heat loss.
2. ii) Evacuated tube collector: In this type, the absorber is surrounded by a glass tube. Because it has a high vacuum, due to this vacuum, the conduction and convection heat loss is reduced. So the energy conversion efficiency is increased. Evacuated tube collector also has two types that include direct flow ETC and Heat pipe ETC.

2. Concentrating collector:

These are further divided into the following two types;

i) Line focus collector: In that, radiation is concentrated in line. The Cylindrical parabolic concentrator and fixed mirror solar concentrator are used. It is also known as a one-axis tracking collector.

ii) Point focus collector: In this collector, radiation is concentrated on the point. Here parabolic dish collectors and hemispherical mirror concentrators are used. It is also known as a two-axis tracking collector.

Wind Energy

The wind is the flow of air. Wind energy is used to generate mechanical power or electricity. Wind energy has been utilized by many civilizations to do many things. Ship sailors used wind energy to sail the boat in the ocean. The windmill is used to draw water from the well and also used to grind the flour and to dry wet clothes.

What is a wind machine?

Wind machine converts wind energy into electrical energy. The components of a wind machine are blades, gearbox, generator and a tower.

Types of wind machines or wind turbines:

i) Based on the axis of rotation

Wind machines are divided into two types according to the axis on which plates move.

• Horizontal axis: In this type, the wind machines' plate rotates on the horizontal axis.
• Vertical axis: This type of wind machine's plate rotate on the vertical axis.

ii) Based on size:

Depending on the availability of air and the speed of air, the wind machines can be of different sizes;

• Small scale: Small scale wind machine gives power up to 2 kilowatts.
• Medium-scale: Medium-scale wind machine gives power from 2 kilowatts to 100 kilowatts.
• Large scale: Large scale wind machine gives power above 100 kilowatts. These machines are installed in the place where the airspeed is more and more air is available.

iii) Based on output:

• Alternative current: This machine gives output in the form of an alternating current (AC).
• Direct current: It gives output in the form of direct current (DC).

iv) Based on the rotational speed of aero turbines:

• Constant speed with variable pitch blades: In this type of machine, speed is kept constant, and the pitch of blades remains variable.
• Nearly constant speed with fixed pitch blades: Here, the speed is kept almost constant, and the pitch of blades is also kept fixed.
• Variable speed with fixed blade: In this type of machine, speed is kept variable, but the pitch of blades remains fixed.

Difference between Solar Energy and Wind Energy