Using liquid natural gas powerships for emergency power is a mistake - Chris Yelland

richjdavies

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Just because they are an IPP does not make them suitable or on the same level. The grid is not designed to carry power both ways. From your own admission these are end users of power where it's stepped down and not up.
Umm... Yes it is.
The grid is a linear system it doesnt care which way the power flows! If there is a system with

1000 MW generation --> grid --> 1000MW consumption
It will work exactly as well if you reverse those arrows
 

eye_suc

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Umm... Yes it is.
The grid is a linear system it doesnt care which way the power flows! If there is a system with

1000 MW generation --> grid --> 1000MW consumption
It will work exactly as well if you reverse those arrows
I have these big pylons close to my home. Does the power flow both ways in those?
 
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richjdavies

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I have these big pylons close to my home. Does the power flow both ways in those?
Your missing a key point...

I didnt say
1000MW --> grid --> 1000000 x 1 kw connections
Did I?

The grid does not grasp direction. It does grasp thickness of wires.

So yes, they will need to find a way to connect up to a biggish MV or HV connection or two. But these are being put in ports where those connections already exist FOR consumption!
 

eye_suc

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Your missing a key point...

I didnt say
1000MW --> grid --> 1000000 x 1 kw connections
Did I?

The grid does not grasp direction. It does grasp thickness of wires.

So yes, they will need to find a way to connect up to a biggish MV or HV connection or two. But these are being put in ports where those connections already exist FOR consumption!
No need to get defensive, it was an honest question. But thanks for the clarification.

I know about as much about this stuff as I do about brain surgery: Just about enough to kill a person.
 

Swa

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Your missing a key point...

I didnt say
1000MW --> grid --> 1000000 x 1 kw connections
Did I?

The grid does not grasp direction. It does grasp thickness of wires.
The grid is not just a bunch of wires. That's the key point you're missing.

So yes, they will need to find a way to connect up to a biggish MV or HV connection or two. But these are being put in ports where those connections already exist FOR consumption!
And that's the thing, they need to find a way to connect it. The connections that exist are for consumption, not transmission.

But we know this was not a decision made by Eskom so no technical considerations were applied.
 

TheChamp

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The grid is not just a bunch of wires. That's the key point you're missing.


And that's the thing, they need to find a way to connect it. The connections that exist are for consumption, not transmission.

But we know this was not a decision made by Eskom so no technical considerations were applied.
So how does transmission happen currently without these powerships?
 

Lupus

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Mainly inland to coast through stepping down.
Okay so how do you explain Koeberg, all the OCTGs which are along the coast, Gariep Dam, Ingula?
The coal plants are up north cause of the coal.
 

Cosmik Debris

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You know IPP stands for Independent Power Provider. Which the power ships are, you also can't build a power station anywhere, neither can a solar, wind, Hydro be built anywhere.
Also that's not how the transmission grid works, also most of the power for the entire country comes from the North.
This would include Cape Towns power. Same as Koeberg assists the grid from the Cape. The power can go both ways.

The grid is designed with the heavy distribution from Mpumalanga to the end users at the coast. The grid ability gets lighter the further you go toward the coast. Plugging in a big vessel at the coast to send power up the grid is like plugging in a 1 MW generator into your home to supply the factory in the next town. Not gonna work.
 
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Lupus

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The grid is designed with the heavy distribution from Mpumalanga to the end users at the coast. The grid ability gets lighter the further you go toward the coast. Plugging in a big vessel at the coast to send power up the grid is like plugging in a 1 MW generator into your home to supply the factory in the next town. Not gonna work.
Right, so OCTGs that are along the coast? The big nuclear power station near the coast? How does that send it up? Magic?
The grid has step up stations along the way for long distances.
 

Swa

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Okay so how do you explain Koeberg, all the OCTGs which are along the coast, Gariep Dam, Ingula?
The coal plants are up north cause of the coal.
You are bringing up exceptions as the norm. They also didn't just magically plug them into the grid and off you go.
 

Cosmik Debris

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You know IPP stands for Independent Power Provider. Which the power ships are, you also can't build a power station anywhere, neither can a solar, wind, Hydro be built anywhere.
Also that's not how the transmission grid works, also most of the power for the entire country comes from the North.
This would include Cape Towns power. Same as Koeberg assists the grid from the Cape. The power can go both ways.

Yes it can. But plugging ships into Richards bay. Nqura and Saldanha will need an upgrade to transmission. Remember that as the water end user of the municipality, they can't plug in a giant bowser at your home to fill the dam.

Everybody jumped up and down with excitement when power ships were announced. Nobody asked the right questions. The thinking was it's like plugging in a generator in your home. It's not.

Power generation with a single exception, Koeberg, is all inland in Mpumalanga. Therefore the distribution infrastructure is heavy in Mpumalanga and gets lighter as it approaches the coast. Plugging a power ship in at the coast is like plugging a big generator into a home in Cape Town to power a factory in Gauteng. Ain't gonna work without a very expensive distribution reversal upgrade.
 

Lupus

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I have these big pylons close to my home. Does the power flow both ways in those?
Well depends on where the low voltage sub station is, electricity likes to go from high to low. So for long distances you need to boost it with step up sub stations.
 

Cosmik Debris

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Umm... Yes it is.
The grid is a linear system it doesnt care which way the power flows! If there is a system with

1000 MW generation --> grid --> 1000MW consumption
It will work exactly as well if you reverse those arrows

The capacity you can plug in at the end user is limited due to the transformers and lines designed to carry the maximum end user requirement x 1.5 safety factor.
 
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Lupus

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Yes it can. But plugging ships into Richards bay. Nqura and Saldanha will need an upgrade to transmission. Remember that as the water end user of the municipality, they can't plug in a giant bowser at your home to fill the dam.

Everybody jumped up and down with excitement when power ships were announced. Nobody asked the right questions. The thinking was it's like plugging in a generator in your home. It's not.

Power generation with a single exception, Koeberg, is all inland in Mpumalanga. Therefore the distribution infrastructure is heavy in Mpumalanga and gets lighter as it approaches the coast. Plugging a power ship in at the coast is like plugging a big generator into a home in Cape Town to power a factory in Gauteng. Ain't gonna work without a very expensive distribution reversal upgrade.
All the OCTGs that are used to assist during high load are already along the coasts, if those are there that means the infrastructure is already there to send it up.
Also CPT had coal stations a long time ago as well.
 
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