Towards Green Energy

• Energy is the ability to do work.
• Different types of energy include mechanical energy, chemical energy, sound energy, light energy, and heat energy.
• Energy can be converted from one form to another.
• Electrical energy is used in various forms in our day-to-day life.
• Electrical energy is produced by using various energy sources and involves the generation of electrical energy.
• The process of generation of electricity involves the use of scientific principles and has advantages and disadvantages.
• Green energy is a type of renewable energy that is used for the generation of electrical energy.
• Most electric power plants are based on the principle of electromagnetic induction, invented by Michael Faraday.
• One solar panel produces a potential difference of 18 V and current of 3A.
• Information about a power plant near your locality can be gathered by visiting the plant.
• Information about solar light, solar water heating system and solar cooker can be gathered for a project.
• Solar photovoltaic cells can produce energy from mW to MW.
• A solar panel can be represented by the sign of a battery.
• Hydroelectric plants are not environment friendly as they cause pollution.
• A schematic diagram of solar thermal electric energy generation is shown below.
• A solar array using solar panels can produce a potential difference of 72 Volts and current of 9 A.
• Electrical energy generation and environment are related.
• Electromagnetic induction principle states that whenever a magnetic field around a conductor changes, a potential difference is generated across the conductor.
• The electrical power generating machine based on this principle is called electric generator.
• Electromagnetic induction principle is used in electric generators to generate electrical energy.
• To generate electricity based on the principle of electromagnetic induction, a generator is required.
• To rotate the generator, a turbine is used and to drive the turbine, an energy source is required.
• In a thermal energy based electric power station, the turbine is rotated using steam.
• Water is heated in a boiler using thermal energy released due to burning of coal.
• Nuclear fission involves the process of neutron absorption.
• An accident in a nuclear power plant can be very fatal as it may result in the release of very harmful radiations.
• A nuclear power plant does not use fossil fuel like coal, therefore, problems like air pollution do not arise.
• The products after fission of nuclear fuel are also radioactive and emit harmful radiations, which are called as nuclear waste.
• Burning of natural gas results in less pollution as compared to burning of coal.
• The schematic of a power plant based on natural gas energy is given in figure 5.14.
• The capacity of major thermal power plants in India are Vindhyanagar in Madhya Pradesh with 4760 MW, Mundra in Gujarat with 4,620 MW, Mundra in Gujarat with 4,000 MW, Tamnaar in Chhattisgarh with 3,400 MW, and Chandrapur in Maharashtra with 3,340 MW.
• The efficiency of a power generation plant based on natural gas energy is higher than that of a power generation plant based on coal.
• Nuclear power plant includes a nuclear reactor for nuclear fission, a system for steam generation from water, a steam turbine, a generator, and a system for conversion of steam back into water.
• In a power generation plant based on natural gas energy, the turbine is run by a gas at very high temperature and pressure generated by combustion of natural gas.
• Nuclear energy is transformed into thermal energy, kinetic energy in steam, kinetic energy in turbine, and electrical energy.
• If sufficient nuclear fuel is available, nuclear power generation can be a good source of electrical energy.
• In a nuclear power plant, a controlled chain reaction results in the release of thermal energy, which is used for electric energy generation.
• Steam of very high temperature and pressure is generated in the boiler.
• The steam is converted back to water by taking out heat from it, a process known as condensation.
• The condenser uses water in a cooling tower to cool the steam and release the heat energy to the atmosphere.