2. • Power system
– It contains three parts namely generation , transmission and distribution of
electricity.
• Generation:
– It means how to generate electricity from available sources.
• Power plant: It is an industrial facility for the generation of electric power. Some of the
power plant classified on the basis of energy source harnessed to generate electricity
are
a. Thermal power plant(uses heat from combustion of fuel)
b. Nuclear power plant(uses nuclear energy like uranium)
c. Hydroelectric power plant(renewable energy source water)
• Hydroelectric Plant(HEP):
– Water flowing in river comprised of potential energy and kinetic energy. In
hydroelectric power plant the potential energy of water is utilized to produce
electricity.
– The plant that produces electricity by use of gravitational force of falling water.
• Head :
– Difference between upper reservoir and lower reservoir.
2
4. • Dam:
– It is a concrete structure built across a river. It is built where height is sufficient to get
maximum potential energy from water. Its function are:
– To provide head of water .
– To create storage or pondage.
• Water Reservoir :
– It stores water.
– Amount of water decides the potential energy.
• Intake or control gates:
– The water from reservoir is released and controlled through these gates. These are called
inlet gates because water enters the power generation unit through these gates.
• Penstock:
– The penstock is the long pipe or the shaft that carries the water flowing from the reservoir
towards the power generation unit, comprised of the turbines and generator.
– The water in the penstock possesses kinetic energy due to its motion and potential energy
due to its height.
4
5. • Water Turbines:
– It converts KE and PE to rotational energy.
• Generator:
– It converts rotational energy (mechanical energy) to electricity.
• Power house:
Fig 1.2
5
6. • Advantages:
– Nepali hydroelectric potential is theoretical estimated at 83,000
megawatt and economically feasible hydropower potential is
approximately 40,000 MW. Enough to secure future economic growth
for itself and its neighbors, carbon free, for the next 500 years.
– Installed capacity 600 MW and largest hydropower project of our
country is kaligandaki A i.e 144 MW.Only 40% of Nepalese population
has access to it.
– Running water is available at free of the cost. It is also a clean fuel(no
smoke,co ) and is a renewable source (that is not depleted ).
– It is the oldest and cheapest method of power generation.( Dams are
designed to last many decades and so can contribute to the
generation of electricity for many years / decades.)
– Quick starting (Once a dam is constructed, electricity can be produced
at a cons tant rate.)
– Less supervising staff is needed.
– Tourism
6
7. • Disadvantange
– Large land requirement with high capital cost.
– Heavy civil engg. Construction work is needed.
– For producing 1 MW electricity it requires nearly 10
crore Npr.
– Flooding of water may take place destroying the
nearby natural environment, villages,towns,etc.
7
