How Electricity Generated, Transmitted And Distributed
Electricity generation, transmission and distribution is a complex engineering process. The process requires huge investment and skilled manpower. The basics of generating electricity remains the same in all forms of electricity such as hydroelectricity, electricity generated using coal, nuclear electricity, renewable energy sources etc.
To understand the process of electricity generation through Hydroelectricity power plants. India is the 7th largest producer of hydroelectric power in the world. As of 30 April 2017, India’s installed utility-scale hydroelectric capacity was 44,594 MW, or 13.5% of its total utility power generation capacity. Additional smaller hydroelectric power units with a total capacity of 4,380 MW (1.3% of its total utility power generation capacity) have been installed.India’s hydroelectric power potential is estimated at 148,700 MW at 60% load factor.
How Hydro Power Plants Work
Hydropower plants capture the energy of falling water to generate electricity. A turbine converts the kinetic energy of falling water into mechanical energy. Then a generator converts the mechanical energy from the turbine into electrical energy.
Parts of a Hydroelectric Plant
Most conventional hydroelectric plants include four major components (see graphic below):
- Dam. Raises the water level of the river to create falling water. Also controls the flow of water. The reservoir that is formed is, in effect, stored energy.
- Turbine. The force of falling water pushing against the turbine’s blades causes the turbine to spin. A water turbine is much like a windmill, except the energy is provided by falling water instead of wind. The turbine converts the kinetic energy of falling water into mechanical energy.
- Generator. Connected to the turbine by shafts and possibly gears so when the turbine spins it causes the generator to spin also. Converts the mechanical energy from the turbine into electric energy. Generators in hydro power plants work just like the generators in other types of power plants.
- Transmission lines. Conduct electricity from the hydro power plant to homes and business.
How Much Electricity Can a Hydroelectric Plant Make?
The amount of electricity a hydropower plant produces depends on two factors:
- How Far the Water Falls. The farther the water falls, the more power it has. Generally, the distance that the water falls depends on the size of the dam. The higher the dam, the farther the water falls and the more power it has. Scientists would say that the power of falling water is “directly proportional” to the distance it falls. In other words, water falling twice as far has twice as much energy.
- Amount of Water Falling. More water falling through the turbine will produce more power. The amount of water available depends on the amount of water flowing down the river. Bigger rivers have more flowing water and can produce more energy. Power is also “directly proportional” to river flow. A river with twice the amount of flowing water as another river can produce twice as much energy.
How Much Electricity A Dam Can Generate?
As we explained above, you need to know two things:
- How far the water falls. First thing that you should know water fall height.
- Amount of water flowing in the river. Second thing you should know the amount of water flowing in the river.
Now all we need to do is a little mathematics. Engineers have found that we can calculate the power of a dam using the following formula:
Power = (Height of Dam) x (River Flow) x (Efficiency) / 11.8
How Is Electricity Transmitted And Distributed To Households ?
- Electricity is made at a generating station by huge generators. Generating stations can use wind, coal, natural gas, or water.
- The current is sent through transformers to increase the voltage to push the power long distances.
- The electrical charge goes through high-voltage transmission lines that stretch across the country.
- It reaches a substation, where the voltage is lowered so it can be sent on smaller power lines.
- It travels through distribution lines to your neighborhood. Smaller transformers reduce the voltage again to make the power safe to use in our homes. These smaller transformers may be mounted on the poles, or sitting on the ground (they’re the big green boxes, called pad mount transformers).
- It connects to your house and passes through a meter that measures how much your family uses.