High Voltage Subsea Poer Cable 1

[petermmm]

Hi,

I would like to estimate the budgetary price of a 3 km long 220 kV sub-sea power cable with 250 MW capacity. there are strong currents in the sea channel to cross. The seabed is rocky. Can you help me with a rough cost estimation? What is the price of the cable?

Thanks in advance!

Peter

 

[racookpe1978]

8<)

Do you want the way-too-low-estimate that a politician or academic "research" study wants to get to encourage subsidies and prove an "economic justification" for spending more tax dollars (by under-estimating the true cost of an uneconomic-but-politically-correct idea)?

Or do you want the real cost that it would take to actually make such a cable and install it in the business world based on a real-world cost-of-interest at 10%?

or so you want a contractor's (hope to get paid) cost to actually build it - complete with contingencies and will-cost realities and inflation and problems and errors?

Or a contractor's (much lower) bid estimate that he/she hopes will win the contract?

Or a politician's/competitor's this-will-be-too-high cost needed to kill any thought of the project continuing?

 

[petermmm]

I would be interested in all this estimates!
Fortunately I am not politician so I will not be able to use the last answer. On the other hand my thoughts are most familiar with the real world, clear business based version (assumed to be built in US).
I would really appreciate if you can help me with that only.

 

[7anoter4]

The total cost of subsea cable installation has 2 parts:
Lay out cost and cable itself cost.

http://www.3utech.com/sites/3utech.com/files/Energy Ocean 08 3U Technologies 080619.pdf

As an approximation see:

http://en.wikipedia.org/wiki/Malta–Sicily_interconnector

The entire project laying out 120 km cable costs 182 millions Euro [1.517 10^6 Euro/km]

 

[FPelec]

Hi,
regarding the Malta-Sicily project, the 182 M€ cost includes also the 230/132 kV GIS substation, shunt reactors and two 250 MVA 230/135 kV autotransformer. I've been deeply involved in the project: the actual cable cost (cable itself and laying) is more realistically "only" about 120 M€.
By the way, the Malta Sicily cable has a copper conductor, in order to reduce the cross section and thus the capacitance, being the cable line very long (about 120 km). If you have to plan a shorter line, probably aluminium would be the most suitable choice for your project, allowing for a significant cost reduction.
Consider also that the procurement strategy used for the Malta Sicily project is turn-key.
The procurement strategy has also a significant impact on the overall cost: having a very large framework agreement with a cable manufacturer, while developing independently the rest of the project, could allow significant cost reduction.

Si duri puer ingeni videtur,
preconem facias vel architectum.

 

[timm33333]

In estimating initial cost, you should also consider whether the cable will be retrieved at the end of its life cycle, or will it be abandoned at the sea-bed. If the cable is to be retrieved, you should take out the future copper price from your present cost estimate. Also consider the future costs of retrieving the copper.

 

[petermmm]

Thank You, especially for the details about Sicily cable!

 

[racookpe1978]

Now, remember that a "single" dry-land-to-dry-land subsea power cable is quoted above.

A wind farm MUST spread its generators out across many separate turbines, each about 1 mile apart, in order to get power generated. So you need to multiply the costs accordingly: The power cable needs to "spiderweb" out to connect everything proportional to the maximum current expected at the highest possible wind speed (before shutdown that is).

So you nave many more connections, many more kilometers of cables than just one point-to-point.