How many MW's can a 133KVA line carry!?

[Doing it for the kids]

Its not as simple as that, I know and so many factors depend on the answer.

But, are we talking, 200 MW, 2000 MW or 20,000 MW!?

TYIA

 

[TechWise]

Its not as simple as that, I know and so many factors depend on the answer.

But, are we talking, 200 MW, 2000 MW or 20,000 MW!?

TYIA

I assume you mean how many megawatts can a 132 kV line carry? This would be the standard voltage in the UK which is considered transmission level in Scotland and distribution level in England.

As you've observed, it's virtually impossible to give a proper answer since there are so many variables. As a VERY rough guestimate, 1000 amps per phase at 132kV works out at around 230MW. However, there are many factors involved, such as:

• Is it overhead or underground?
• Is it winter or summer?
• What size are the conductors?
• How long is it?
• What size transformer is at either end? What is the busbar arrangement?
• What are the protection considerations? What is the fault level?
• What are the reactive power limitations?

I don't recall the exact value, but National Grid will not allow more generation to be connected to any one set of towers than they have backup diesel capacity. The theory being they could never allow one pylon to fall down and take out more generation than they could rapidly replace. I believe that number was 2GW at one point but I can't recall accurately.

 

[Doing it for the kids]

I assume you mean how many megawatts can a 132 kV line carry? This would be the standard voltage in the UK which is considered transmission level in Scotland and distribution level in England.

As you've observed, it's virtually impossible to give a proper answer since there are so many variables. As a VERY rough guestimate, 1000 amps per phase at 132kV works out at around 230MW. However, there are many factors involved, such as:

• Is it overhead or underground?
• Is it winter or summer?
• What size are the conductors?
• How long is it?
• What size transformer is at either end? What is the busbar arrangement?
• What are the protection considerations? What is the fault level?
• What are the reactive power limitations?

I don't recall the exact value, but National Grid will not allow more generation to be connected to any one set of towers than they have backup diesel capacity. The theory being they could never allow one pylon to fall down and take out more generation than they could rapidly replace. I believe that number was 2GW at one point but I can't recall accurately.

Thanks

yup 132 KVA was what I meant.

When you say 230 MW, is this per Tower or per side of Tower. Assuming per Tower?

 

[TechWise]

Thanks

yup 132 KVA was what I meant.

When you say 230 MW, is this per Tower or per side of Tower. Assuming per Tower?

No, that's per circuit or per side of the tower. It's a very rough guide though because you often run into one of the other problems I listed long before you hit the theoretical thermal limit of the line.

 

[Doing it for the kids]

So 4 - 500 MW per tower rather than say 1000 or 1500?!

 

[TechWise]

So 4 - 500 MW per tower rather than say 1000 or 1500?!

Yes but it depends on the size of the conductors which is pretty much impossible to determine unless you're the utility company. There's even different alloys and types of conductor used so it doesn't just depend on the physical size.

 

[Netherfield]

Its not as simple as that, I know and so many factors depend on the answer.

But, are we talking, 200 MW, 2000 MW or 20,000 MW!?

TYIA

Have you got a big welding job to do?

 

[Doing it for the kids]

Have you got a big welding job to do?

ha, something like that!

 

[Exfarmer]

It depends on the number of lines and the size of the lines.
so the towers will carry 3 layers of lines.
this is the three phases
the lines will often be in groups of 4 on each side of the Tower per layer, maybe more.
It is then how much each Line can carry amperage wise that counts.
a wire can carry so many amps irrespective of voltage. The longer the line, the greater the amps, the greater the voltage drop and the greater the heat build up in the line.
as heat builds up, the greater the voltage loss.
so the longer the line, ie. North of Scotland to South of England the more the loss in voltage and so less amperage which can be pushed through it

 

[Doing it for the kids]

thanks all. I think I have enough info now to confirm what I suspected

 

[Courier]

Near us the lines originally installed in the early 60's have been re-strung with groups of 3 instead of groups of 4 but when we enquired we were told that the newer 3 grouping could actually carry a higher current than the older 4's.

 

[fermerboy]

We have had the towers through us re strung with wire twice as thick and voltage ramped to 275Kv to get the power moved South. And they are now on about going to 400kv!!!
We are next to the UKs largest substation and second biggest substation in Europe though, and I'm led to believe the only one in the world with 11kv, 33kv, 132kv, 275kv, 400kv on one site. Thats not counting the ordinary 415 and 240v!!!