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  • Who of us hasn't left the TV on, even though we are not watching?

  • Who hasn't left the lights on, even though we are not in the room?

  • Nowadays, electric power is regarded as a common commodity. Just as the sun rises every

  • day, we believe that electricity simply is there.

  • Electricity appears to be a straightforward issue. You press a button and we have instant

  • electricity. It's as if it's hidden in the socket. But is this really how it is?

  • Just one look out of the window reminds us that Electric power comes from somewhere.

  • It travels along the cables on the pylons of the Hellenic Public Power Corporation.

  • If we follow these cables, we might be able to discover where it comes from.

  • In Greece, the largest amount of electrical power is generated in Western Macedonia. Six

  • in ten houses get their electricity from the electric power stations in this area.

  • Western Macedonia is the heart of electrical energy in our country.

  • Let's look then at how electrical energy that we take for granted, is generated.

  • In Western Macedonia, there is a large quantity of coal known as lignite.

  • With the use of large machines it is mined from the ground. Some of the machines are

  • taller than an eighteen-storey building and weigh more than five thousand cars.

  • After lignite is mined, it is taken to the electricity generating power plants on conveyor belts.

  • In all of Western Macedonia, there are 270 km of conveyor belts.

  • This is one and a half times the distance from Florina to Thessaloniki!

  • When the lignite arrives at the station, the process of energy production begins.

  • First, it goes into a furnace burner where it is burnt. From the combustion, smoke is

  • produced which escapes through the stacks of the power station.

  • The burner generates heat which heats up a large water tank known as the boiler.

  • The water that is heated in the boiler becomes steam.

  • The high pressure steam goes into a turbine. The turbine has large bladed rotors, like

  • the sails of a windmill which pushed by the steam, rotate at a high speed.

  • In turn, these bladed rotors activate a magnet that generates the electric current. This

  • magnet is part of a device known as an electric generator.

  • Lastly, the steam is separated: Some of the steam is distributed to the surrounding cities

  • and villages via a network of pipes to provide heating. This process is known as district heating.

  • The remaining steam cools and condenses into water and goes back to the boiler for reheating.

  • Steam is used for chilling by spraying the pipes which convey it with water.

  • The water evaporates and is released into the atmosphere through those characteristically large,

  • thick cooling towers that appear to be forming clouds in the sky!

  • Combustion, steam, turbine, electrical generator, electricity.

  • Once electricity is generated in the power plant, it is distributed all over Greece through cables,

  • which are found on the transmission line towers.

  • It is through these that it arrives in our houses.

  • Highly-trained personnel are involved at every stage of the process of generating electrical power.

  • When at some point a conveyor belt tears,

  • the welders are called in. They join additional pieces onto the conveyor belt to make it operate again.

  • When a machine breaks down, the electrician fixes it.

  • Thanks to them, the machines in the plant operate like clockwork!

  • The Rope Access Technicians work is very difficult. They climb the electric power pylons to fix them.

  • They change the destroyed cables and join the cut ones. They undergo special training

  • in order to climb the pylons safely.

  • Apart from all the highly-trained personnel, there are also the machine-operators,

  • the excavator drivers, and the technicians.

  • All of these people work hard so that the power plant operates non-stop the whole day.

  • We saw that in order to have electrical power in our homes, hard work is required by both

  • people and machines. However, the generation of electricity also affects the environment.

  • When lignite is mined from the ground, the natural landscape is destroyed.

  • When lignite combusts, the air we breathe is polluted.

  • The towers that transmit electric power to our homes are dangerous at close distances.

  • Furthermore, at some time the lignite resources will finish. We estimate that up to now

  • half of the reserves in Western Macedonia have been used up.

  • This means that in a few years from now we will run out of lignite.

  • We have already started using other sources of energy

  • such as, the sun, water, wind and waves.

  • Definitely, the sun will be around for many years, rising daily without our help.

  • In contrast, electric power generation, as we have seen,

  • is a most demanding process.

  • Each time we press a button, let's not forget

  • the long journey made by electric power to our homes.

Who of us hasn't left the TV on, even though we are not watching?


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B1 中級 美國腔

電能的歷程 (The Journey of Electrical Energy)

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    噹噹 發佈於 2021 年 01 月 14 日