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Transmission of Power

The increasing demand for electric energy and its consumption in our society raise many questions that need to be considered before a new transmission line is planned for more electric power. One of them is how the power should be transported from the power plant to the consumer.
Overhead Power Lines
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Vocabulary

Make sure you understand these words before you read the text. Use the dictionary in the link collection to look up new words:

  1. consumption
  2. consumer
  3. supplier
  4. concealed
  5. visible
  6. pylon
  7. eyesore
  8. violation
  9. residential
  10. densely
  11. radiation
  12. environmental
  13. protection
  14. maintain
  15. currently
  16. spoil
  17. dependence
  18. emergency
  19. switch on
  20. benefit

Overhead vs. Underground Cable Systems

Transmission of Power

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Transport of electric power is a question of method and procedure seen in relation to other concerns, such as cost and protection of the environment.

Overhead Systems

Overhead cable systems are very dominating and visible in nature. The towering pylons of the grid are seen as an eyesore by many. Most people will agree that they are a violation of untouched nature. In residential and densely populated areas, underground transmission is usual, at least in Norway. That is mainly to reduce the risk of electromagnetic radiation from the cables, but also to avoid the ugly web of overhead cables above the streets. However, in the USA it is usual to see overhead cable systems also in towns and cities. Look for this the next time you see a picture or a movie from small-town America.


Whenever a new transmission line is planned, it will initiate a debate raising questions of environmental protection vs. economic considerations. An overhead cable system is cheaper to construct and it is easier to maintain and troubleshoot. Thus, the distribution companies primarily prefer to put up overhead transmission lines to save money.

New Power Lines in Norway

In Norway, there is currently a controversy concerning transmission of power to parts of Western Norway and the arguments follow the same pattern. The environmentalists claim that the overhead cables will spoil the beauty of the fjords and mountains, and want the cables to go subsea across the fjords. They even say that overhead lines will be bad for tourism in the area. However, the companies and many politicians seem to focus on the financial aspects and prefer to go for an overhead solution.

Dependence on Electric Power

We are totally dependent on electric power in our modern society. Imagine what would happen if there was a worldwide power cut and no emergency generators would work. It would mean total chaos. The least of your problems would be cold water in the tap and a black TV screen… So the next time you switch on the light or enjoy a hot shower, you should stop a minute and think about the benefits of electric power and how it is transported to your home.

Comprehension

  1. How can overhead / underground cable systems be compared with open and concealed wiring indoors?
  2. Can you think of any reasons why overhead systems are more common in the USA?
  3. Make a list of pros and cons for the different cable systems.
Key
  1. Overhead cables and open wiring are both visible, and not very pretty to look at, but both are easily maintained. However, an open indoor wiring system is more expensive than a concealed system, while overhead cable systems are cheaper to construct than underground systems. (Open wiring is more expensive because it takes more cable length to go neatly round each corner and along the skirting, and it takes more time to put up than a concealed wiring system.)
  2. The main reason is probably the cost. Also, in the USA there are many private companies involved in both production and transmission of power, so there is no state or federal control of the process.
  3. Overhead cables: Pros – cheaper to construct and easier to maintain and troubleshoot. Cons – visually ugly, radiation Underground cables: Pros – the environment will be preserved, reduce radiation Cons – expensive and difficult to maintain

Relatert innhold

Norway is fortunate when it comes to generating electric power. The abundancy of water makes it easy and fairly cheap to produce electricity.

Note: All electric installations in a house must be carried out by a certified, approved electrician.

CC BY-SASkrevet av Jan-Louis Nagel.
Sist faglig oppdatert 29.11.2018

Læringsressurser

Elektro og datateknologi (programme-specific resources)