Detailed Description :

Background

Scroby Sands is one of the first major offshore windfarms to be developed in the UK. It is one of 18 offshore windfarms proposed as part of the Crown Estates Round 1 licensing awards. The windfarm is located 2.5 km offshore Great Yarmouth on the coast of East Anglia.

The development comprises 30 X 2MW Vestas V80 turbines, 60-metre high, producing 60 Mega Watts of electricity, enough to power an equivalent of 41,000 homes in the area. The cables were brought ashore and connected to the local grid network system.

Scope of Work

The development of the Scroby Sands Offshore Windfarm constitutes four major contracts let by E-ON UK Renewables Offshore Wind Ltd (EROWL). ode was awarded the ‘Project Management Services’ to manage, monitor and co-ordinate the performance of the four contractors in accordance with their contractual requirements. The four contracts being -

• 1. Cable supply Contract (Pirelli Cables supplied the onshore cables for the project.) This contract covered the supply of 40,000 m of 33kV single core 500mm2 CWS Land and 13,300m of 24 Fibre singlemode Optical cable to be connected to the offshore cables at the ‘beach head joining pit’ and terminated at the ‘EDF Energy grid substation at Admiralty Road’.
• 2. Onshore Cable Installation Contract (This contract was awarded to NACAP Infrastructure UK Ltd) This contract covered the installation of all onshore cables as specified above.
• 3. Offshore EPIC Contract consisting – Supply and installation of the piles, towers, nacelles, blades, interfield cables. Marine Operations and Commissioning of the field. (EPIC Contract awarded to Vestas Celtic Wind Technology Ltd who provided all manufactured items from their facility in Campbelltown in Scotland and sub-contracted the offshore installation works to Mammoet / Van Oord, CNS, A2Sea and Seacore Ltd)
• 4. Onshore cable connection to (PES) EDF Energy at Admiralty Road Substation. This contract covered the modifications to the substation to accept the incoming cable and the physical connection and testing of previously specified cables to the local grid network system.

The project commenced in February 2003 with project completion date targeted for Mid October 2004, with ode’s contract completion December 2004.

During project completion ode have also been employed by E-ON UK Renewables Offshore Lind Ltd to manage the ‘Defects Period’ taking the contract through until December 2005.

DETAILED WORKSCOPE

The key services, activities and areas of responsibility of ode during the execution of this Project Management contract were :

Community Relations :

Provision of historical background information with community relation issues specifically with local officials.

Contract Administration & Interface Management :

Provision of a Project Management Team to oversee the contracts. Provision of engineering services, offices and administration facilities, document control (including development and co-ordination of a Interface Register). Liaison between contractors and third parties such as local group interests and marine operators etc.

Reports & Meetings :

Using Key Performance Indicators (KPI’s) to assess the true status of the works, ode provided Management, engineering and secretarial resources, for the production of reports, technical studies and minutes of meetings including HAZOP , HAZID and HS&E reports or QA/QC as necessary.

Health, Safety and Environmental including QA/AC :

HS&E and QA/QC personnel and resources provided feed back on all Safety and Environmental aspects throughout the design and during construction and installation phases. Review was undertaken of site installation procedures and risk assessments Site safety audits were conducted to ensure that the contractor works to CDM Regulations and HSE and Environmental guidelines. Environmental audits were undertaken on Contractor(s) activities to review and monitor the environmental effectiveness with specific regard to Waste Management, Contingency Plans and Environmental Management Systems. Provision of Quality Assurance and Control engineering reviews and the monitoring of all activities of the contracts, from design through to manufacture, installation and commissioning. Review and approval of all installation, construction, marine and fabrication procedures, qualifications, acceptance of manufacturing and offshore works.

Contractors Programme Review :

Detail review and monitoring of the contractor’s programme plus assistance on issues of construction sequencing to take account of local environmental factors.

Design & Manufacturing :

Personnel and resources to manage the design and to monitor the manufacturing process. Engineers will review and approve (in conjunction with EROWL) Operating and Maintenance Manuals and final ‘as-built’ packages. Witnessing and monitoring of FAT’s for the manufacturing of the cables, piles, towers, nacelles, and blades. Co-ordinating with local authorities, marine and police departments for delivery and pre-assembly of items such as Turbine / Nacelle, Blade / rotor and hub.

Construction & Commissioning :

Monitor, and report on all aspects of the offshore works. Provision of offshore supervision and 24 hr communication network throughout the offshore campaigns.

Onshore Cabling :

Manage all phases of the works providing liaison between local district government offices and the contractor for gaining consents and approvals to commence works.

Offshore Piling :

Provision of offshore supervisor on the installation vessel, maintaining a 24 hour presence. Daily reports provided giving progress of the works, areas of concern, vessel and personnel movements and weather reports.

Pre-Assembly & Delivery of Large Items :

In conjunction with the Contractor, ode ensured liaison with local authorities was undertaken to ensure minimum disruption to traffic and marine movements prior to delivery of major bulk equipment (Nacelles, Blades, Hubs) to the designated lay-down area for the pre-assembly and pre-installation works. Monitoring of logistics of specific routes and methods of delivery were monitored regarding accessibility by road or sea, height and width restrictions and crane availability for on-loading and off-loading from the quayside.

Offshore Tower Installation :

Supervision for the tower installation with focus on safe lifting and construction quality control, tolerance, bolting sequence and bolt tensioning and welding monitoring. Issue of daily report providing all relevant information was ensured.

Offshore Turbine Installation :

Supervising engineer was on board all vessels throughout the process monitoring the lifting operations of the nacelle, rotor hub and blade installation.

Offshore Cable Installation :

During the offshore cable installation, the supervisor was onboard the lay barge and in addition to the offshore daily reports observed all activities such as trenching, cable tensioning, touchdown monitoring and backfilling.

Connection to PES and Commissioning :

Under the supervision of the E&I Engineer the final connections and terminations were made. Commissioning was undertaken as soon as practical after the installation of each turbine. The commissioning of the SCADA system, including the annex to the EDF Energy substation 33kV switch room was implemented and the 240 hour & 120 hour trial running periods completed.