Electricity question on the power generated by power stations.

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The discussion revolves around calculating the power lost per kilometer due to heating in 400kV supergrid conductors, given their resistance and current. The power stations generate electricity at 25kV, with a typical demand of 6000MW in the north-west of England. The output voltage from generators is 240kV, and transformers increase this to 400kV, resulting in a current of 15kA. The resistance of the conductors is specified as 0.034Ω/km. Participants emphasize the importance of showing work in problem-solving to receive effective assistance.
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Homework Statement



2)The power stations providing electricity for the National Grid generate electricity at 25kV. The typical demand on an average winter's day in the north-west of England is 6000MW. The current output form the generators is 240kV. Transformers raise the transmission voltage to 400kV. Assuming 100% efficiency in the transformers, the current is 15kA. Each pair of 400kV supergrid conductors has a resistance of 0.034Ωk/m.
How much power is lost per kilometre heating the conductors?
Books answer:7.65MW

Homework Equations



P=W/t=VQ/t=VI
V=IR
R=VI

The Attempt at a Solution


Can type my working out sorry.
 
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Delpo said:

Homework Statement



2)The power stations providing electricity for the National Grid generate electricity at 25kV. The typical demand on an average winter's day in the north-west of England is 6000MW. The current output form the generators is 240kV. Transformers raise the transmission voltage to 400kV. Assuming 100% efficiency in the transformers, the current is 15kA. Each pair of 400kV supergrid conductors has a resistance of 0.034Ωk/m.
How much power is lost per kilometre heating the conductors?
Books answer:7.65MW

Homework Equations



P=W/t=VQ/t=VI
V=IR
R=VI

The Attempt at a Solution


Can type my working out sorry.

We don't know how to help if you don't show your attempt...
 
We can't help you unless we can see you have tried to solve it.
 
Are you sure you copied that text correctly? It seems to contain several errors. For example it should be 0.034Ω/km, not 0.034Ωk/m.
So each km of conductor has a resistance of 0.034Ω. The current is 15kA.
Now you just have to apply your equations.
V=IR
P=VI
 

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