Key Physics Concepts Behind Effective Solar Energy Utilization
The energy that is solar can be used by man in a planned direct way nowadays. There are two methods of solar energy conversion that are: the photothermal and the photoelectric. In this article we are going to discover few of the very important information regarding solar energy and its utilization as well. The article is dealing with the analysis of conservation of the photothermal in high latitude countries.
There are Different types of solar that are active and passive systems. The more reliable the solar system is the higher the temperature requirements are there. The technology which is required is more modern and sophisticated and the construction of the system together with the automatic control is a more complicated process though.
How to Utilize Solar Energy in Home
The solar energy is the energy which is emitted by the star sun in the form of radiant light. This radian light is then harnessed by humans using a variety of methods such as the solar heating, the photovoltaic cells etc. It is inexhaustible. The sources of energy such as solar energy do not usually belong to anyone and hence it is said to be free. The amount of solar energy that is received by the world was calculated once to be approx. near 3000-50000 exajoules that is EJ which is much larger than the total world energy consumption of 600 EJ.
The operation of a photovoltaic that is PV cell requires 3 basic attributes that are:
The light absorption that is generating either electron-hole pairs.
The charge separation which carries opposite charges.
The extraction separates those carriers to an external circuit.
To reduce the consumption of electricity of the building:
At First : If we want to save on electricity costs with or without PV then we should first eliminate devices and its appliances that use too much of it. These include the standby devices, which are the incandescent bulbs or the light bulbs and water heaters.
Then we need to install LEDs instead of light bulbs.
Usually the single which is the largest cost factor is lighting. We can say that the obsolete light bulbs only use about ten percent of the electricity that is to make light.
About 90 percent are lost as heat.
They are said to produce heat rather than light this is because they are based on a glowing filament made of tungsten.
The LEDs which are the modern ones use almost all of the electricity to make light. We can clearly notice this from the fact that they stay cool, that is there is much less loss. A good LED generally needs about a tenth of the electricity to produce the same amount of light.
And because it does not heat up so much quicker so it lasts much longer.
And we can say that the price of LEDs has come down so much that exchanging them for regular light bulbs pays off within one or two years. The same is true for industrial systems of lighting which often use mercury and the vapour lamps. These things too use up a lot of electricity and can easily be replaced by LEDs.
What are the Challenges of Solar Energy?
The Cost and T&D Losses: is that the solar PV is some years away from true cost competitiveness and from being able to compete on the same scale. That is other energy generation technologies.
However we can say that the government is supporting R&D activities by establishing research centers and funding such initiatives.
The government has even tied up with world-renowned universities to bring down the installation cost of solar sources power and is focusing on upgradation of substations and T&D lines to reduce T&D losses.
Solar power refers to the conversion of the radiant energy of the sun energy in the form of light into electricity. This is done by the cell which is known as the photovoltaic cell also called as the Solar Cell. The metal silicon which is along with germanium and such is a part of a group of elements called semiconductors. It's said to be the electrical conductivity that lies in between the conductors and the metals and the insulators. The element silicon is the key ingredient in solar cells.
Sunlight is said to be composed of tiny balls of energy that are called photons. The photons in sunlight usually strike the solar cell and they are absorbed by the silicon atoms that the cell is made of. The sunlight that consists of energy packets that are photons excites the protons and the electrons and causes it to jump to a higher energy level. It jumps from a valence stationary orbit to a conduction band where it is mobile. Once these are excited the electron has two options : first the electron can dissipate the energy that it gained as heat and then return to its original position. Second that the electron can easily travel through the body creating a current.
FAQs on Harnessing Solar Energy: Principles, Benefits, and Applications
1. What is meant by harnessing solar energy as per the CBSE syllabus?
Harnessing solar energy is the process of capturing radiant light and heat from the Sun and converting it into a usable form of energy. For students, this primarily involves understanding two key technologies: solar thermal technology, which uses sunlight to create heat, and photovoltaic (PV) technology, which converts sunlight directly into electricity.
2. What is the fundamental principle behind a solar photovoltaic (PV) cell?
The fundamental principle is the photovoltaic effect. When sunlight, which consists of energy packets called photons, strikes a semiconductor material like silicon in a PV cell, it transfers energy to the electrons. These energised electrons break free from their atoms and flow, creating a direct electric current (DC). This process is a direct conversion of light energy into electrical energy.
3. What are some common examples of how solar energy is used in daily life?
Solar energy has several practical applications that are important to know. These include:
- Solar Water Heaters: These devices use solar thermal principles to absorb sunlight and heat water for domestic use.
- Solar Cookers: A box-type solar cooker uses a glass sheet and mirrors to trap heat and cook food, converting solar energy to thermal energy.
- Solar Panels for Electricity: Photovoltaic panels on rooftops generate electricity for homes, reducing reliance on the grid.
- Solar-powered Devices: Smaller applications include solar-powered streetlights, calculators, and traffic signals.
4. What are the key environmental benefits of harnessing solar energy?
The primary benefit of solar energy is that it is a clean and renewable resource. Unlike fossil fuels, it does not produce harmful greenhouse gases like carbon dioxide during operation, thus not contributing to global warming. It is an inexhaustible source of energy that helps conserve finite natural resources and reduces air and water pollution associated with conventional power generation.
5. How does a solar cooker work, and why is its interior typically painted black?
A solar cooker works by trapping heat from the sun. It uses a transparent glass sheet that allows sunlight to enter but prevents the heat from escaping, creating a greenhouse effect. The interior of the cooker is painted black because black surfaces are the best absorbers of light and heat. This maximises the amount of solar radiation absorbed, allowing the cooker to reach high temperatures needed for cooking.
6. What is the core difference between a solar thermal device and a solar photovoltaic cell?
The core difference lies in the type of energy they produce.
- A solar thermal device (like a solar water heater) is designed to capture sunlight and convert it into heat (thermal energy).
- A solar photovoltaic cell is designed to capture sunlight and convert it directly into electricity (electrical energy) using the photovoltaic effect.
7. What are the main limitations that prevent the widespread use of solar energy?
Despite its benefits, solar energy has several limitations:
- Intermittency: Solar power can only be generated during the day and is significantly reduced by cloudy weather or rain.
- High Initial Cost: The cost of manufacturing and installing solar panels can be expensive, though prices are decreasing.
- Large Space Requirement: Generating a large amount of electricity requires installing solar panels over a vast area.
- Energy Storage: Storing the electricity generated during the day for use at night requires expensive battery systems, which adds to the overall cost and complexity.
