Subsea Cable Protection & Laying Costs | Part 2 of 5

Published 16 Sep 2019

Subsea Cable Protection Systems

♦ Republished by Chris Dodds 

with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)

Subsea Cables

 

 

First Subsea is the world’s leading developer of subsea connection technology, supplying, installing and decommissioning.

Subsea power cables on offshore wind farms are typically protected by means of burial.

This is a well proven means of cable protection used in other offshore industries.

However, at either end of offshore wind array cables they transition from burial, up through the water and into the wind turbine foundation. This free spanning section of cable is susceptible to what can be substantial wave and current loads.

These loads introduce movement and bending into the subsea cable which, without cable protection, can lead to over-bending, over-tensioning, fatigue and abrasion damage.

This exposed subsea cable is traditionally ‘protected’ by means of a relatively expensive and complex proprietary Cable Protection System (CPS).

Our 2nd Article on Subsea Cable Protection Systems focuses on Subsea Cable Protection & Laying Costs.

As part of our product awareness feature on Cable Protection Systems we look at the time taken to install, focusing on the critical path timings, that impact on the installation costs.

Cable lay construction vessels command market rates in excess of €150,000 a day, due to their ability to reel, carry and deploy cable using dynamic positioning, this figure excludes crew/fuel.

Most large cable lay vessels have the ability to pre-assemble and prepare the cable protection system on the runway off the critical path as they perform other operations, so the deck preparation times which take on average an hour have been discounted.

The critical path clock for the CPS product starts as it is deployed over the chute located at the stern of the vessel. The graph shown below shows the times for a number of cable pull ins with a crew new to our system. Our quickest time was 38 minutes from overboarding to connection.

After the first few pull-ins the team averaged 45 mins. From first hand observations on another CPS we saved over an 1hr on critical path.

Saving an hour on critical path, could provide a saving of €7,000, small change you may think. Think again Typically 150 CPS per project could save over €1,000.000 When selecting CPS consider the overall CAPEX not just the product cost.

Subsea Cables Protection | Further Information

 

➡ If you would like a copy of the report, please contact Chris Dodds [email protected] 

Subsea Cable Protection & Laying Costs

LV, MV & HV CABLE JOINTING, EARTHING, SUBSTATION & ELECTRICAL EQPT

Thorne & Derrick are Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.

We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.

Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.

t: 0191 410 4292 | e: [email protected] | www.powerandcables.com

We provide expert technical support and supply from a multi-million pound stock holding:

  • Cable Joints, Terminations & Connectors Earthing & Lightning Protection
  • Cable Accessories – Lugs, Glands
  • Circuit Protection & Fuses
  • Cable Cleats & Clamps Electrical Safety Equipment
  • Cable Pulling & Laying Equipment
  • Arc Flash Protection & Clothing
  • Cable Duct Seals & Transit Systems Surge Arresters & Bushings

Further Reading: