Forms of Energy
Various forms of energy such as light, heat, sound, electrical, nuclear, chemical, etc are briefly explained.
Energy exists in many different forms. Examples of these are: light energy, heat energy, mechanical energy, gravitational energy, electrical energy, sound energy, chemical energy, nuclear or atomic energy and so on. Each form can be converted or changed into the other forms.
Although there are many specific types of energy, the two major forms are Kinetic Energy and Potential Energy.
- Kinetic energy is the energy in moving objects or mass. Examples include mechanical energy, electrical energy etc.
- Potential energy is any form of energy that has stored potential that can be put to future use. Examples include nuclear energy, chemical energy, etc.
Chemical energy is energy stored in the bonds of chemical compounds (atoms and molecules).Chemical energy is released in a chemical reaction, often in the form of heat. For example, we use the chemical energy in fuels like wood, coal by burning them.
Electrical energy is the energy carried by moving electrons in an electric conductor. It is one of the most common and useful forms of energy. Example – Lightening. Other forms of energy are also converted to electrical energy. For example, power plants convert chemical energy stored in fuels like coal into electricity through various changes in its form.
Mechanical energy is the energy a substance or system has because of its motion. For example machines use mechanical energy to do work.
Thermal energy is the energy a substance or system has related to its temperature, i.e., the energy of moving or vibrating molecules. For example, we use the solar radiation to cook food.
Nuclear energy is the energy that is trapped inside each atom. Nuclear energy can be produced either by the fusion (combining atoms) or fission (splitting of atoms) process. The fission process is the widely used method.
Uranium is the key raw material. Uranium is mined from many places around the world. It is processed (to get enriched uranium, i.e. the radioactive isotope) into tiny pellets. These pellets are loaded into long rods that are put into the power plant's reactor. Inside the reactor of an atomic power plant, uranium atoms are split apart in controlled chain reaction. Other fissile material includes plutonium and thorium.
In a chain reaction, particles released by the splitting of the atom strike other uranium atoms and split them. The particles released by this further split other atoms in a chain process. In nuclear power plants, control rods are used to keep the splitting regulated, so that it does not occur too fast. These are called moderators.
The chain reaction gives off heat energy. This heat energy is used to boil heavy water in the core of the reactor. So, instead of burning a fuel, nuclear power plants use the energy released by the chain reaction to change the energy of atoms into heat energy. The heavy water from around the nuclear core is sent to another section of the power plant. Here it heats another set of pipes filled with water to make steam. The steam in this second set of pipes rotates a turbine to generate electricity.
Pros and cons of nuclear power
- Nuclear power generation does emit relatively low amounts of carbon dioxide (CO2). The contribution of nuclear power plants to global warming is therefore relatively little.
- It is possible to generate a high amount of electrical energy in one single plant.
- The problem of safe disposal of radioactive waste exists
- There exists high risks and the consequences of damage is great when accidents happen
- The raw material Uranium is a scarce resource. Its supply is estimated to last only for the next 30 to 60 years, depending on the actual demand.
There are thirty five countries including India in the world which generate electricity from nuclear source. According to the data published in March 2017, by Power Reactor Information System (PRIS) of International Atomic Energy Agency (IAEA), India is ranked at 13th position in terms of power generation. However, it stood at 7th position in terms of number of reactors in operation country- wise, globally.
The current installed nuclear power capacity is 5780 MW. It is expected to increase to 10080 MW on progressive completion of projects under commissioning/ construction by 2019. At present there are 21 nuclear power reactors under operation in the country with an installed generating capacity of 5780 MWe. The target for electricity generation from nuclear power during 2016-17 is 36000 MU excluding infirm (non commercial) power. The generation in 2016-17 (upto February 2017) has been 34137 MUs (excluding infirm power). In addition, 2086 MUs of infirm (non-commercial) power has also been generated in the current year (upto February 2017).
Gravitational energy is that energy held by an object in a gravitational field. Examples include water flowing down a waterfall.
Source: Time for Change