Power Generation

at a

Glance

Power System

Power system mainly contains three parts namely:

1. Power Generation

2. Power Transmission

3. Power Distribution.

Generation means how to generate electricity from

the available source and there are various methods

to generate electricity.

Power Generation Types

Conventional Sources

1. Thermal power

2. Hydro power

3. Nuclear power

Non-Conventional Sources

1. Wind power

2. Solar power

3. Biomass power

4. Tidal wave energy

5. Geo Thermal Energy

Electricity Generation (Conventional) :

Thermal Power

Thermal power generation plant or thermal power station is the most

conventional source of electric power. Thermal power plant is also referred

as coal thermal power plant and steam turbine power plant, where steam

is used to drive a steam turbine.

In a conventional thermal power station, a fuel is used to heat water, which

gives off steam at high pressure. This in turn drives turbines to create

electricity.

Electricity Generation (Conventional) :

Thermal Power

The theory of thermal power station or working of thermal power station

is very simple. A power generation plant mainly consists of alternator

runs with help of steam turbine. The steam is obtained from high

pressure boilers. This in turn drives turbines to create electricity.

In thermal generating stations coal, oil, natural gas, etc are employed as

primary sources of energy.

Typical Coal Based Thermal Power Plant:

ENNORE - Thermal Power Plant:

TUTICORIN - Thermal Power Plant:

Electricity Generation (Conventional):

Hydro power:

Hydro-power or water power is power derived from the energy of falling water and

running water, which may be harnessed for useful purposes.

In hydro power plant we use gravitational force of fluid water to run the turbine

which is coupled with electric generator to produce electricity.

The big advantage of hydro power is the water which the main stuff to produce

electricity in hydro power plant is free, it not contain any type of pollution and

after generated electricity the price of electricity is average not too much high.

Electricity Generation (Conventional):

Hydro power:

The power extracted from the water depends on the volume and on the difference

in height between the source and the water's outflow. This height difference is

called the head. The amount of potential energy in water is proportional to the

head. A large pipe (the "penstock") delivers water to the turbine.

The cost of hydroelectricity is relatively low, making it a competitive source of

renewable electricity. Most hydroelectric power comes from the potential energy of

dammed water driving a water turbine and generator.

Schematic of Hydro Power Generation :

Maravakandy (Nilgiris) – Hydro Electic Power Plant:

Mettur – Hydro Electic Power Plant:

Electricity Generation (Conventional):

Nuclear Power Plant:

Electricity made by nuclear power plants is called nuclear power.

Nuclear power plant is a thermal power station in which the heat source is a

nuclear reactor. In a nuclear power plant where the nuclear reaction makes heat,

called a reactor.

Nuclear power plants use uranium as fuel. When the reactor is on, uranium atoms

inside the reactor split into two smaller atoms. When uranium atoms split, they

give off a large amount of heat.

This splitting of atoms is called Fission.

Electricity Generation (Conventional):

Nuclear Power Plant:

The most popular atoms to fission are uranium and plutonium. Uranium atoms are

slightly radioactive. The atoms produced when uranium breaks apart are strongly

radioactive.

Today, fission only happens in nuclear reactors. In nuclear reactors, fission only

happens when the reactors parts are arranged properly.

Nuclear power plants are usually near water to remove the heat the reactor

makes. Some nuclear power plants use cooling towers to do this.

Schematic Layout Nuclear Power Plant:

Koodangulam Nuclear Power Plant:

Kaiga Atomic Power Plant:

Electricity Generation (Non -conventional) :

Wind power:

Wind power is the conversion of wind energy into a useful form of energy,

such as using wind turbines to make electrical power.

The wind has kinetic energy (movement energy) which is changed into

mechanical energy by the blades on the turbine. The turbine then turns a

generator which creates electrical energy (voltage).

The turbine is usually connected by a gearbox to help control the speed it

turns the generator at.

Electricity Generation (Non -conventional) :

Wind power:

Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely

distributed, clean, produces no greenhouse gas emissions during operation

and uses little land.

Wind Farm – group of wind turbines in the same location used to produce

electric power. A large wind farm may consist of several hundred individual

wind turbines, and cover an extended area of hundreds of square miles.

Working Principle of Wind Power Energy

Typical Windfarm – Suzlon – Karnataka

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Typical Windfarm – Offshore

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Electricity Generation (Non -conventional) :

Solar power:

Solar power is the conversion of sunlight into electricity, either directly using

photovoltaic (PV), or indirectly using concentrated solar power (CS).

Concentrated solar power systems use lenses or mirrors and tracking systems

to focus a large area of sunlight into a small beam.

A solar cell, or photovoltaic cell (PV), is a device that converts light into electric

current using the photovoltaic effect.

Electricity Generation (Non -conventional) :

Solar power:

Solar power is the conversion of sunlight into electricity, either directly using

photovoltaic (PV), or indirectly using concentrated solar power (CS).

Solar Cells produce direct current (DC) power which fluctuates with the

sunlight's intensity. For practical use this usually requires conversion to

alternating current (AC), through the use of inverters.

Multiple solar cells are connected inside modules. Modules are wired together

to form arrays, then tied to an inverter, which produces power at the desired

voltage, and for AC, the desired frequency/phase.

Working Principle of Solar Power Energy

1

Typical Solar Power Plant in Gujarat

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Typical Solar Power Plant in Rajasthan

Electricity Generation (Non -conventional) :

Bio- Mass Power:

Biomass is biological material derived from living, or recently living organisms. It

most often refers to plants or plant-based materials.

As an energy source, biomass can either be used directly via combustion to

produce heat, or indirectly after converting it to various forms of biofuel.

Conversion of biomass to biofuel can be achieved by different methods which

are classified into: thermal, chemical, & biochemical methods.

Wood remains the largest biomass energy sources today. Examples include forest

residues, yard clippings, wood chips and even municipal solid waste.

Electricity Generation (Non -conventional) :

Bio- Mass Power:

There are five basic categories of material:

1. Virgin wood : from forestry, arboricultural activities or from wood processing.

2. Energy crops: high yield crops grown specifically for energy applications.

3. Agricultural residues: residues from agriculture harvesting or processing.

4. Food waste: from food and drink manufacture, preparation and processing,

and post-consumer waste.

5. Industrial waste and co-products from manufacturing and industrial

processes.

Electricity Generation (Non -conventional) :

Bio- Mass Power:

Biomass can be converted to other usable forms of energy like methane gas or

transportation fuels like ethanol and biodiesel. Rotting garbage, and agricultural

and human waste, all release methane gas—also called “ Landfill Gas” or

"biogas."

Crops, such as corn and sugar cane, can be fermented to produce the

transportation fuel, ethanol. Biodiesel, another transportation fuel, can be

produced from left-over food products like vegetable oils and animal fats.

Layout of Bio-Mass Power Plant

Typical Bio-Mass Power Plant

10 MW - Bio-Mass Power Plant in Maharastra

30 MW - Bio-Mass Power Plant in Maharastra

Electricity Generation (Non -conventional) :

Tidal Wave Power:

( When the sun doesn’t shine and the wind don’t blow, Tides go

with the flow).

Tidal power, also called tidal energy, is a form of hydropower that converts the

energy of tides into useful forms of power, mainly electricity.

Although not yet widely used, tidal power has potential for future electricity

generation. Tides are more predictable than wind energy and solar power.

Among sources of renewable energy, tidal power has traditionally suffered from

relatively high cost and limited availability of sites with sufficiently high tidal

ranges or flow velocities, thus constricting its total availability.

Electricity Generation (Non -conventional) :

Tidal Wave Power:

A tidal generator converts the energy of tidal flows into electricity. Greater tidal

variation and higher tidal current velocities can dramatically increase the

potential of a site for tidal electricity generation.

Tidal stream generators (or TSGs) make use of the kinetic energy of moving

water to power turbines, in a similar way to wind turbines.

Because the Earth's tides are ultimately due to gravitational interaction with the

Moon and Sun and the Earth's rotation, tidal power is practically inexhaustible

and classified as a renewable energy resource.

Layout of typical Tidal Power Generation

Layout of typical Tidal Power Generation

Various Designs of Hydroelectric, Wave and Tidal Power

The Rance Tidal Power Station in France

a

Tidal Power Station in Alaska (U.S.A).

Electricity Generation (Non -conventional) :

Geo-Thermal Power:

Geothermal energy is thermal energy generated and stored in the Earth.

Geothermal electricity is electricity generated from geothermal energy.

In the simplest geothermal power plant, called a dry steam plant, a well is

drilled into the rock to tap a steam reservoir. The steam escapes the well

under great pressure, which is used to turn a turbine & generate electricity.

Geothermal power is cost effective, reliable, sustainable, and environmentally

friendly, but has been limited to areas near tectonic plate boundaries..

Electricity Generation (Non -conventional) :

Types of Geo-Thermal Power Plant:

All geothermal power plants use steam to turn large turbines, which run

electrical generators are basically two types.

In the Geysers Geothermal area, dry steam from below ground is used

directly in the steam turbines.

In other areas of the state, super-hot water is "flashed" into steam

within the power plant, and that steam turns the turbine.

Electricity Generation (Non -conventional) :

Types of Geo-Thermal Power Plant:

Geo-Thermal Power Plant in Iceland :

Geo-Thermal Power Plant in Spain :