Where Is the Error in This Power Transmission Calculation?

In summary, power lost during transmission refers to the dissipation of electrical energy as heat during the transfer of electricity. This can be caused by factors such as resistance, electromagnetic interference, and transformer inefficiencies. The more power that is lost, the less efficient the electrical grid becomes, leading to increased costs and environmental impact. However, measures such as using higher voltage transmission lines and implementing smart grid technologies can help reduce power loss during transmission. It is a significant issue that requires ongoing research and solutions to mitigate its impact on the efficiency and cost of the electrical grid, as well as environmental pollution.
  • #1
songoku
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Homework Statement
A power station needs to deliver 20 MW of power to a city. This power is generated at 16 kV and then stepped up to 240 kV. The total resistance of the transmission cables is 20 kΩ. Show the power loss during transmission is 139 kW
Relevant Equations
P = V.I

##P=I^2 R##
The current in transmission cables = 20 MW / 240 kV = 250 / 3 A

Power loss in cables =(250/3)2 x 20 x 103 = 139 MW , which is not possible

Where is my mistake?

Thanks
 
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  • #2
I think there must be a typo in the ohmic resistance of the transmission cable, most likely it is ##20\Omega##. A typical copper cable has a resistance of around ##8\Omega## per km, so if we take it that the total resistance is ##20000\Omega## this means that the power station is located 2500km away from the city...Which of course doesn't look right.
 
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  • #3
Thank you very much Delta2
 
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FAQ: Where Is the Error in This Power Transmission Calculation?

What is power lost during transmission?

Power lost during transmission refers to the amount of energy that is dissipated or lost as heat during the process of transmitting electricity from a power source to a destination.

What causes power loss during transmission?

Power loss during transmission is caused by a variety of factors, including resistance in the wires or cables used to transmit the electricity, fluctuations in voltage, and imperfect connections between components.

How does power loss during transmission affect the efficiency of a system?

Power loss during transmission can significantly impact the efficiency of a system, as it reduces the amount of usable energy that reaches the destination. This can result in higher energy costs and decreased performance.

What are some ways to reduce power loss during transmission?

There are several strategies for reducing power loss during transmission, including using thicker wires or cables with lower resistance, improving the quality of connections between components, and implementing voltage regulation techniques.

Is it possible to completely eliminate power loss during transmission?

While it is not possible to completely eliminate power loss during transmission, it can be significantly reduced through careful design and implementation of transmission systems. However, some level of power loss is inevitable due to the laws of thermodynamics.

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