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Electricity Generation

Horizontal axis wind turbine

How Do Wind Turbines Work?

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Thermal Power Plant

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Hydroelectric Power Plant

Diesel power plant

Oil Power Plant

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Coal Power Plant

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Combined Cycle Power Plant

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Nuclear Power Plants

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Geothermal Power Plant

How electricity is generated
Before we talk about how electricity is generated, we must illustrate what is electricity, electricity is the most widespread forms of energy we all through the world use for lighting, heating, and cooling homes, powering television and computers and so on in all applications around us, and simply electricity is the energy produced by the flow of electric charge through a conductor.

How electricity is generated

What is electricity:
To understand how electricity is generated, we must go to atom, why! Because electricity is just the flow of electrons from one body to another, and as we know the atom consists of electrons which are negatively charged particles, protons which are positively charged particles and neutrons which are neutrally charged or simply they don’t have any charge.

atom structure

According to those words if we have two objects A and B with 10 electrons and 10 protons in each, and due to any reason, 2 electrons flow away from the outer orbit of the object A to object B.

So, we have 8 electrons in object A and 12 protons in object B.

And according to that object, A will have a positive charge because of a deficit of electrons.

While object B will have a negative charge due to excess electrons and it’s simplest is how electricity is generated

And as we can’t challenge physics, especially the law of conversation of energy which states that the energy neither is created nor be destroyed, we would use another kind of energy as fuel. So, this law leads us to the history of electricity, are you ready!!.

History of electricity:
We will start from 1820 with the fundamental principles of electricity generation discovered by Michael Faraday.

He discovered a method for generating electricity from the movement of a loop of wire or a disc of copper between the poles of a magnet.

When the magnets move an electric current flows through the wire so electricity generated.

And in 1870 the production of electricity started with the coupling of the dynamo to the hydraulic turbine.

Also at this time, the mechanical production of electric power becomes a reason for the second industrial revolution after it was only produces by chemical reactions or using battery cells.

Thomas Edison and Nikola Tesla contributed in creating inventions using the energy.

And we can say that the generation of electricity at central power stations started in 1882 with Pearl Street Station.

when a steam engine driving a dynamo produced a Dc current which powered the public lighting on the street.

But today, of course, those old gas fueled street lights adapted to electric power which become used in public buildings, in businesses and also in public transport.

Nowadays there is a variety of energy sources such as:

coal, nuclear, natural gas, hydroelectric, wind generators, oil, tidal power, geothermal sources.

as well as solar energy and it would be more sources in the future who knows.

And there is the annual electricity generation in the world:

Annual electricity generation from renewable energy

Annual electricity generation

Methods of generating electricity:
And as electricity is the process of generating electric power from a primary energy source we will need the help of any method to convert these primary sources and we restored to:

We use the electric generators to transform the kinetic energy into electricity based on Faraday’s law. And these generators use electromagnetic induction in working as a mechanical energy force the generator to rotate.

It’s the transformation of chemical energy into electricity.

and the simple form of this type is the battery.

Today it’s most important in portable and mobile applications.

Photovoltaic effect:
It’s the transformation of light into electricity we can see in solar cells.

While the photovoltaic panels convert the sunlight directly into electrical energy.

And we can use in remote sites where there is no access to a power grid or supplement electricity for individual homes and businesses.

Sources to generate electricity:
How electricity is generated?? Now we can use many sources to generate energy; there would be renewable sources like:

solar, wind, water, tidal and biomass, which are free, environment-friendly and infinitely available sources.

Or nonrenewable sources like:

coal, oil and natural gas, which are the most used, but limited available sources.

Let’s explain each type … you can check this article also (what is power plant and types of power plants):

Hydroelectricity (hydroelectric power):
Hydroelectricity is the power produces by river or ocean water.

And the power plants we use based on the gravitational effect which will illustrate in details later.

hydroelectric power

Wind energy system:
In wind system we use wind turbines to convert wind energy to electrical energy, as the wind turbines turn the wind energy into a kinetic energy and the rotation of this kinetic energy makes the induction generator rotates so, the generator converts the kinetic energy into electrical energy.

Wind Energy System

Solar energy system:
The solar energy system is the best for power generation because it’s the most available source, and we can get energy by:

A photovoltaic cell which made up of silicon as we connect many cells in series or parallel to create a solar panel.
And the other way by using mirrors in the sunlight and we use the produced heat to convert the water into steam, and the steam, by the way, rotates the turbines.
solar energy system

Coal energy system(fossil fuel energy system):
In this system, we burn coal in a boiler and use the produced heat to convert water into steam, the temperature and the pressure of this steam spins the generator to produce the electrical energy.

Coal energy system

Nuclear energy system:
In the nuclear system, we use uranium in the nuclear reactor to generate the heat required to turn the turbines and produce electricity.

nuclear energy system

We can produce energy by 1 Kg of uranium = by burning 4500 tonnes of coal or 2000 tonnes of oil.

Geothermal energy system:
Geothermal energy is the energy from within the earth.

As we know the earth is too hot from inside.

So we can use this heat to turn turbines and produce electricity.

Geothermal energy system

Tidal energy generation:
We can produce electricity from the tides by using the change in height of the tides or using the flow of the water, and in both ways, we use the pressure of water to turn turbines and generate electricity.

Tidal energy generation

Hydrogen energy system:
Hydrogen is the most common available element on earth and we can get it from water ( H2O).

So, we can use in conventional internal combustion engines or with fuel cells where we convert chemical energy directly into electrical energy.

Can you imagine that we need 50KWh to produce 1KG of hydrogen by electrolysis.

Which means that the cost of producing electricity is clearly crucial.

hydrogen energy system

Wave energy system:
In this system, we depend on the motion of waves on the oceans.

So, we use the pressure of the waves to turn turbines which then uses to produce electricity.

wave energy system

Biomass energy system:
It’s the energy produces from organic materials like:

crops, plants, trees, wood chips and animal waste.

We Use for heat production, power production, transport fuel, and biomaterials.

But unfortunately, it produces a large amount of carbon dioxide.

biomass energy system

In conclusion, we can say that those are the most commonly used types that can help to know How electricity is generated and we will mention each type in details in our coming articles and we would find more types to study.

And here you are some countries rate of electrical generation:

what are the sources of electricity

What are the sources of electricity? … When we talk about how electricity is generated, we took a hint about sources of electricity or sources used to generate electricity, and we said there are renewable and nonrenewable sources, but after I deep in sources of electricity I ask myself why we give electricity this big importance, did you also do that!

Importance of electricity:
From the moment we open our eyes in the morning until we go to bed in the evening we use electricity at home, office, school, powering televisions, radio, grinder, tape-recorder, heater, washing machine, charging mobiles, and everywhere around us we find electricity.

And to be more definite we use electricity in:

We use electricity in all technical engineering activities as with building ad welding certain materials.

Communication and transport:
Electricity is the main reason for enjoying all the facilities of transport and communication.

Electricity is very important for the modern treatment of many diseases is surgical, the powerful light the doctors need over the body of the patient upon the operating table, and so on.

Entertainment programs:
Like television, cinema, radio, tape-recorder, shows and everywhere where we need to rest.

We need electricity here for getting grills for the windows, gates and other iron and steel materials, for polishing mosaic floors and also cutting marble pieces.

Briefly, electricity is the backbone of our life so it’s axiomatic to have many sources of electricity, let’s discuss them.

what are the sources of electricity
We can say that we use 10 different sources of energy to generate power, and we discover other types all the time, but they don’t reach the stage to be used to provide the power we need.

what are the sources of electricity

Let’s see the most common types of sources of electricity to reply our main question … what are the sources of electricity? (you can check also … what is power plant and types of power plants):

1- Solar energy:
In the solar energy system, we use collector panels to create conditions that can turn the sun into a kind of power and that happens by:

The photovoltaic cell which made up of silicon as we connect many cells in series or parallel to create a solar panel.
And the other way by using mirrors in the sunlight and we use the produced heat to convert the water into steam, and the steam, by the way, rotates the turbines.
And we usually use large solar panel fields in the desert because there would be plentiful amounts of sun available to gather enough power used to charge small substations, and also supplement electricity for many home applications.

Solar system

Advantages of solar energy:
Solar energy is the most available source so it has the advantages of:

It’s a clean, renewable energy source.
The transmission cost is approximately zero for a stand-alone system.
The cost of maintenance is low.
The electricity generated is environment-friendly, as it doesn’t cause pollution or noise.
It is the ideal for remote location as we don’t need to link to the grid.
And the PVs we use work without sound, air, moving parts, or even water emissions.
Disadvantages of solar energy:
And unfortunately, there are some drawbacks like:

The high initial cost of establishing the system.
We can generate electricity only when the sun is shining.
We need a large area for bulk production.
The system affected by the weather.
The batteries we need to store the solar energy is costly.
2- Wind energy:
When the sun heats the air and cooler air moves in to replace or when the air moving it causes the wind, which becomes a more and more common of sources of energy. As the pressure of the wind turns large turbines which then turn generators to produce electricity.

wind energy

Advantages of wind energy:
The wind is a renewable source so it’s unlimited, free and clean.
The cost of operation is very little.
We can use this system to generate power in a remote location.
It can be combined with solar energy to generate a sustainable energy source in developing countries.
Disadvantages of wind energy:
Unfortunately, we can meet some troubles as:

We can’t get the same amount of electricity in all time.
We need a big open area.
It’s complex in maintenance so the maintenance cost is high.
The construction of the wind turbine is expensive.
We have low output electricity.
3- Geothermal energy:
Some countries use geothermal energy which produces from the heat of the earth for many years for hot water, cooking, and heating.

Geothermal energy

As the slow decay of radioactive particles produces continuously high temperatures inside the earth’s crust and the presented hot rocks below the earth heats up the water to produce steam, which is then helped to move turbines and those turbines power the generators to produce electricity.

Advantages of geothermal energy:
Geothermal energy is environment-friendly because it’s clean and sustainable.
We can extract the energy without burning fossil fuel.
The carbon dioxide produced by this system is about one-sixth, which is very fair.
The geothermal energy is always available.
It’s inexpensive.
Disadvantages of geothermal energy:
Unfortunately, the geothermal energy can only produce at selected sites throughout the world.
The initial cost is high for individual households.
Although the geothermal sites can provide heat for many decades, some locations may cool down.
Another problem is the disposal of some geothermal fluids which may contain toxic materials.
4- Hydrogen energy:
It’s the energy produced from water stored in huge dams as we use hydroelectric turbines and generators to transfer the water released from these dams into electricity. As the water contains the hydrogen (H2O) which can be used as fuel for generating electricity, power ships, vehicles, homes, industrial and rockets only when it’s separated.

hydrogen energy

And the most famous source of this hydroelectric power is in the snow mountains.

Advantages of hydrogen energy:
It’s inexpensive and doesn’t contribute to the greenhouse effect.
It’s renewable and doesn’t leave any toxic emission in the atmosphere.
Also, The hydrogen is more efficient than other sources.
Disadvantages of hydrogen energy:
It isn’t safe as it’s hugely flammable and frequently makes headlines for its potential dangers.
It’s daunting to transport hydrogen due to its lightness.
It needs to be stored and transported under high pressure because it has a low density.
5- Tidal energy:
The Tidal energy produced from the rise and fall of the tides as the kinetic energy of incoming and outgoing tides is converted into electrical energy and that can happen by:

A Tidal barrages: these barrages are similar in construction to a dam, and in this type we use gates to control the level and flow rate of the water to allow the tidal basin to fill on the incoming high tides and to empty through an electricity turbine, and in this system we can use a two-way tidal power system to generate electricity from both the incoming and outgoing tides.
Tidal turbines: they are similar to wind turbines and we place them on the seabed where there is strong tidal flow, but they must be much sturdier and heavier to withstand the water which is an 800 times danger than the air.
Tidal fences: it’s a type of tidal power system which has a vertical axis turbine mounted on a fence or row placed on the seabed, and it’s similar to tidal turbines as the electricity produced from the water passing through the turbines, and from the end of 2016 no tidal fence operates.
tidal energy

Advantages of tidal energy:
It’s a renewable energy source so the energy produced is free and clean.
Tidal energy is environment-friendly as it doesn’t produce greenhouse gases.
The cost of operation or maintenance is relatively low.
It has a high efficiency around 80%.
We don’t need to burn any fuel to produce energy.
The power plants have a very long life.
The low noise pollution.
The tidal barrages also provide protection against flooding and land damage.
Disadvantages of tidal energy:
It’s not a constant energy source because it depends on the strength and flow of the tides.
The initial construction cost of power plants is high.
The tides happen only twice a day so we can only produce electricity at this time.
We need a suitable site where we have a consistently strong tidal.
It’s a danger to fish and other sea-life.
Also, We use long underwater cables which cause high power distribution costs.
6- Wave energy:
what are the sources of electricity? … It’s produced from the waves in the oceans, the waves contain tremendous energy potential and we can use wave power devices to extract this energy and then converts it into electrical energy.

wave energy

And there are popular four technologies for wave power as:

Terminator devices: we extend this devices perpendicular to the direction of the wave to capture or reflect the power of the wave, and they are typically onshore or near shore.
And terminator devices depend on the wave climate and the devices missions to produce a power rating of 500 KW to 2 MW.

Attenuators: they are long multi-segment floating structures which are oriented parallel to the direction of the waves, and they extract energy by using restraints at the bow of the device and along its length.
Point absorber: it’s a floating structure with components which move relative to each other due to wave action, and it often looks like floating oceanographic buoys.
Overtopping devices: they have reservoirs which filled by incoming waves causing a slight buildup of water pressure, and we use the energy of the falling water to turn hydro turbines and produce electrical power.
Advantages of wave energy:
It’s a renewable source which is unlimited by a season.
Wave energy is environmentally friendly, clean source as it doesn’t produce pollution.
There are a variety of ways to gather this energy from current gathering.
And the great advantage is that it’s easily predictable and we can calculate the amount of energy produced.
Also, It’s very safe as it doesn’t cause any damage to the earth.
Disadvantages of wave energy:
Unfortunately, it’s available only in places where there are oceans.
It can disturb the sea life around it as it creates noise and there would be toxic chemicals.
Using the power plants on the coastline may damage the marine ecosystem and disturb the private and commercial vessels.
It depends on the wavelength, wave speed and the density of the water which isn’t consistent all the time.
It also depends on the weather which may affect the generation of energy.
7- Hydroelectric energy:
what are the sources of electricity? … In hydroelectric energy, we use the falling water to turn turbines, which produce mechanical energy and therefore a hydroelectric generator converts this mechanical energy into electrical power.

hydroelectric energy

Advantages of hydroelectric energy:
It’s a renewable, clean and safe energy.
We can use it in the service instantly.
The water uses in this process can be reused for irrigation and other purposes.
The cost of running and maintenance is low.
Also, We don’t need any fuel transportation.
Disadvantages of hydroelectric energy:
The initial cost of the plant is high.
We need a long transmission line because we locate the plants in the hilly area.
Also, unfortunately, it depends on the weather.
8- Biomass energy:
what are the sources of electricity? … It’s the energy from landfill or rubbish dumps, and also comes from organic materials like animal and plant matter, when the above materials decompose or rot we can capture and process them to create electricity as they are collected, dried, then filtered and fed by popes to a gas generator to burn gas and therefore produce electricity.

biomass energy

Advantages of biomass energy:
We can say that it’s a renewable source because the organic materials (wood, crop waste, garbage, sewage sludge) are never-ending.
It’s bountiful, so we wouldn’t encounter problems as experiencing with fossil-based sources of fuel.
The production cost is mainly low.
Also, it can minimize the impacts of waste in landfills to the environment.
Disadvantages of biomass energy:
It isn’t entirely clear as it may increase methane gases which are harmful to the earth’s ozone layer.
It would be a result of deforestation as the biomass sources have to be utilized sustainably.
Also, The plant matter needs a sufficient amount of water to get by, which may affect the availability of water to humans and wildlife.
9- Nuclear power:
what are the sources of electricity? … In nuclear power, we produce electricity depending on the heat generated from the splitting of uranium atoms in a fission process which is used to produce steam, and then the steam turn power turbines which therefore produce electrical energy which then supplies the surrounding community.

nuclear power

Advantages of nuclear power:
The space we need is less than the required for thermal or hydro power plants.
The electrical energy produced from a signal plant is high enough.
We need a small quantity of fuel.
Also, The running of plants doesn’t affect the weather or any foreign suppliers.
Disadvantages of nuclear power:
The initial construction cost is high.
The cost of operation and maintenance is also high.
Also, There is a radioactive waste.
10- Fossil fuel energy (coal, oil and natural gas):
what are the sources of electricity? … It’s the most popular source of energy around the world, as we burn coal, oil and natural gas to heat the water to convert to a steam until this steam has the pressure and temperature needed to turn the turbines, and the turbines produce the electrical energy.

Fossil Fuel

Advantages of fossil fuel energy:
It’s capable to produce a huge amount of electricity in just a signal location.
Fossil fuels are cheap and reliable.
Coal is abundant supply and when we use it in power plants, it’s very cost-effective.
We can use easy task pipes to transport oil and gas to the power stations.
Also, It’s easy to construct a power station in any location because we can easily transport as large as quantities of fuel for the power plant.
Disadvantages of fossil fuel energy:
The main disadvantage is the pollution as they give off carbon dioxide, which causes a greenhouse effect when burning.
They need a continuous large amount of fuel.
And They may create environmental damage as it would spill during transport.
what are the sources of electricity? … After we listed the main sources of electricity we can’t assert that there is the best type to use instead of all the other sources of electricity but it is your choice to use the type suit to the place and the conditions you have.

Electric power transmission
Electric power transmission is a major process in the electrical system. So, in simple definition: transmission is the process of movement of electricity from power plants to distribution grids in populated areas.

We use interconnected lines (transmission network) to facilitate this movement over long distances.

Someone may come and ask why we don’t simply produce electricity where we need it! This needs a back in time journey to discover why and how they transmit electricity by less cost and high efficiency.
History of transmission:
We can start from Menlo Park, New Jersey in the 1880s when Thomas Edison operated the Pearl Street station. The station distributed power over underground copper lines using 100 K W direct current (DC) to serve small networks that covered only a few city blocks.
Pearl Street station
To make this DC networks safe … it operated at low voltage, the initial cost of the station was high.

Most of the produced power lost as heat and at the same time power cannot be transmitted very far so it was so inefficient.
Westinghouse’s Niagra power plant
In 1896 the Westinghouse’s Niagara power plant constructed as the first commercial alternating current (AC) power system designed by G. Westinghouse, Stanley, and O. Shallenberger.

There was the invention of the AC induction motor by N. Tesla in 1888 and the Tesla coil in 1891.

All of this by using new transformers to increase and decrease the voltage helped to transmit electricity over a long distance.

Actually, there was 37 MW output power which was several hundred times powerful than Edison’s station.

The station developed several times by many engineers until they built the hydroelectric power station. This station used transformers to increase the generated voltage from 2200 volt to 11000 volts before transmitting it.

As a result of the induction motor invention, all industries revolutionized, thus producing power washing machines, vacuum cleaners, and refrigerators.

These inventions increased demand and spread out of electricity became greater.

At this time it was also important to make laws to facilitate regulation of electric utilities, protect the financial health of public utilities, the supply of electricity, and at the same time, retail natural gas.

The Public Utility Holding company allowed the following in 1935:

There is a limit of the geographic spread of utility holding companies.
They control the amount of debt and loans.
Cross-subsidies regulated of unregulated business to regulated business.
Common ownership of electricity and natural gas was limited.

The concentration of economic power in just a few companies was reduced and electricity became a regulated business.
How does electricity transmission work?
To understand how electricity is transmitted, we must start from the steam-generating plant where fuel is burned to drive a turbine which in turn produces electricity.

The electricity produced in generating stations is at low voltage so we use step-up transformers at generating plants to raise the voltage up to the transmission voltage (69, 115, 230, 500, or 765 Kv). In order to transmit it over high voltage transmission lines too long distances.

Large industries need 2400 to 4160 V to run heavy machinery so there are step-down transformers in transmission substations to reduce electricity to 69 or 34 Kv to be suitable for usage.

At the same time homes, schools, small businesses, and farms need 120/240 or 120/208 V so we also use transformers to step down the electricity.
Components of transmission system:
Actually, we need many components to successfully deliver electricity from generating station to distribution. So we have primary components as:
Transmission towers:
They are the most visible component of the transmission system that carries the heavy transmission conductor at a sufficient, safe height and sustains all kinds of natural calamities.
Power lines (conductors):
From the name, they are lines that carry the electric power from sending to receiving end. These conductors usually are copper, aluminum, and aluminum conductor steel reinforced.
We use substation to transfer voltage to a higher or lower level of voltage. So there would be various types and classifications of substations depending on the amount of voltage, equipment on-site, and transformation desired.

They are transformers to convert voltage levels, large amounts of protection and control equipment, and circuit breakers.

Besides that, we use substations to provide the ties, switching, transformation, and protection for transmission and distribution systems
It’s a substation that delivers generated power from the power source to the nearest transmission line.

The switchyard operates at a single voltage level therefore it doesn’t have transformers and it uses connections and interconnections.