If you were asked how valuable electricity is in your life, what would your answer be? The common answer is yes, it’s really valuable because we are very used to it. This will be the answer of a person living in 2019. But, in 1850, William Gladstone had asked the same question to the scientist Michael Faraday and he answered “One day sir, you may tax it”. This was the vision associated with electricity that in the coming future it will be a very essential commodity for everyone.
The earliest electric distribution systems were located in the area surrounding the Pearl Street Power Station in Manhattan, and in Menlo Park, NJ. Both were built by Thomas Edison in 1882. These systems used direct current (DC) and were very inefficient, requiring electric generating stations to be close to the users, generally within a mile. These types of generation-transmission systems were called distributed generation systems.
In the 1890s, further development and refinements of distribution systems were made. The most significant of these improvements was the design of alternating-current (AC), high-voltage distribution transmission systems. This was significant because these new AC lines permitted electric power to be transmitted over much longer distances than the inefficient DC system did.
In 1896, George Westinghouse built an 11,000-volt AC line to connect Niagara Falls to Buffalo, NY – a distance of 20 miles. From that point on, the generation of electricity and the voltage capacity of transmission lines grew rapidly, while the distance from the point of production to the consumer grew wider. This resulted in a move away from the localized production of electricity to much larger, regionalized producers that could generate more electricity at one location and move it longer distances on the growing electrical grid.
We have come across this statement many a time that “Energy cannot created be or destroyed, it can only be converted from one form to another”. So, the electrical energy is actually generated by converting it from many different energy sources like thermal, nuclear, hydro, solar, wind, etc.
Thermal Power Plant
Currently, the majority of the electricity generated is done by thermal power plants. So, what is the basic principle that is implied in these plants. The electricity that is generated here is with the help of steam turbines. So, at first the water is converted into steam by combustion of fuel and the fuel used in these plants is normally coal. So, after the water has been heated and converted into steam, the steam is used to move the turbines which in turn is connected to a generator which generates electricity by converting the mechanical energy into electrical energy.
Advantages of the steam power plant is that it is economical(initially) as compared to the power generation plants. It also requires less plant area as compared to a hydro power plant.
Disadvantages of this is that due to the combustion of fuels, the fuels which are non-renewable sources of energy are getting depleted, moreover this was one of the causes for air pollution. The efficiency of such plants was just 35% to 40%.
So, alternatives had to be explored and the next alternative that we are going to discuss is a hydro power plant.
Hydro Power Plant
The kinetic energy of water is converted to electrical energy in this method. The water is allowed to fall from great heights which helps it to have a high kinetic energy by the time it reaches the turbine.
Then the rotation of turbine and generation of electricity is same as that of the steam power plant.
The advantage is that there is no combustion of fuel and this is a renewable energy source.
The disadvantage is that huge infrastructure is required.
Solar Power Plant
With the advancements in technology like photo voltaic cells been invented which can convert the solar energy into electrical energy and the advancements in power electronics solar power plants are increasing at a rapid rate. We can currently see many street lights being run by solar electricity.
India currently generates over 20GW of energy just by solar plants.
Disadvantage is the high level of maintenance that these solar panels require. Regular cleaning has to be done so that there is no dust accumulated over the panels due to which proper and efficient conversion doesn’t take place.
We have seen at many places that numerous wind mills are installed, but why? Usually in such places where there is no obstruction to the flow of wind like above the mountains, in desert, near the sea shore open fields where inhabitation is not that much wind mills are setup to ensure that the wind energy is properly utilised. The principle implied here is that due to wind the blades rotate and a generator converts this rotational energy into electrical energy.
Disadvantages of this system is that if there is not enough wind and the blades are not locked instead of generating electricity, it starts drawing electricity.
These are the sources by which electricity is generated in huge amounts like Giga Watts and this generated electricity is then transmitted to different places.
There are other sources of energy which can be converted to electrical energy like the principle of operation of batteries is the conversion of chemical energy into electrical energy. Piezo-electricity is generated with the help of piezo-electric materials. The principle of operation here is that whenever the dimensions of these piezo-electric materials change due to any force applied on them, they store charge in them. This charge is then later used.
So, these are just the reformations of the present, there is a lot to come in the future as well which we might not be able to imagine right now. So, never take electrical energy for granted and always be energy efficient.