Walney 2 is the second phase of the Walney Offshore Wind Farm project, which has already seen the construction of one wind farm in the Irish Sea, 15km off Walney Island in Cumbria. Both of the wind farms will comprise 51 Siemens turbines and the development will have a combined capacity of 367.2MW. When the second phase is complete, the 73km² Walney Offshore Wind Farm will provide energy to power 320,000 homes.
The scheme has been implemented through a combined partnership of DONG Energy, Scottish and Southern Energy (SSE) and OPW, with DONG Energy acting as the leading construction and operations partner.
A 3-month installation operation for foundations and cabling took place in April 2011, closely followed by a 3-month installation for offshore substations and a 6-month installation operation for the 51 turbines in May 2011.
Whilst Walney 1 took a year to complete, Walney 2 was scheduled for completion in around half the time due to an overlapping construction schedule that was specifically designed to speed up the construction process.
Crane barges, tugs and jack-up vessels worked out of ports in the East Irish Sea during the early construction period, whilst a number of smaller support vessels provided personnel transfer services and conducted environmental monitoring.
DONG Energy CEO, Anders Eldrup, said: “Walney 2 is the world’s fastest installation of an offshore wind farm and underlines DONG Energy’s position as a strong market leader within offshore wind. We’ve developed our techniques for faster and more cost efficient installation methods and this is an important step in the continuing drive to reduce the construction costs of offshore wind farms.”
On 1st November 2011 Walney 2 began delivering CO2-free electricity via turbine F14, the first of its completed turbines. Power was supplied to the national grid via the Stanah 132kV onshore substation near Blackpool and a further ten turbines began operation shortly afterwards.
SSE Chief Operating Officer, Colin Hood, said:
“This was a major milestone in the development of the Walney Offshore Wind Farm and it demonstrated the excellent progress that is being made on the project.
“As the UK’s leading generator of electricity from renewable sources, SSE is committed to helping increase the amount of renewable electricity generation in the UK and the export of electricity at Walney is a step towards achieving this.”
Commission work was temporarily delayed in December 2011 when difficult weather conditions made site access impossible. Although wind turbines are specifically installed in areas where they can benefit from high winds, if weather conditions deteriorate, work must be placed on hold for health and safety reasons.
Prior to the change in weather, array cables that connect the Walney 2 substation to the shore were successfully laid on the seabed. However, one cable still needed to be terminated once conditions improved.
Approximately 70,000 tonnes of stone has been supplied and delivered from the Stainton Quarry to provide scour protection for the turbine foundations. The stones will be placed along a 15 metre radius around the monopole in order to reduce sand and material erosion caused by the current.
DONG Site Manager, Lars Alber, said: “The first phase of the works went well and we are now looking forward to completing the second phase with the same success.”
Walney 1 Offshore Wind Farm was completed in 2010 and began generating power on the 13th January 2011. In October 2011, Walney Windfarms Limited completed the sale of transmission assets of Walney 1 to Blue Transmission Walney 1 Limited for £105 million. Power for Walney 1 is supplied to the national grid through the onshore transformer station in Heysham, with an approximate annual net energy of 663GWh.
With a power capacity set to increase to 600MW upon the completion of Walney 2, Walney Offshore Wind Farm will make a substantial contribution to the UK’s production of renewable energy in 2012.
Batt At Sea Ltd
Batt At Sea Ltd is a specialist in wind farm support vessels. It uses marine vehicles to transport technicians to off-shore turbine towers and to carry out diving support operations. The company is also involved in Marine Mammal Observation (MMO) and Passive Acoustic Monitoring (PAM) services to monitor wildlife in areas that surround wind farms. Batt At Sea Ltd is an equal opportunities employer, with as many female members of staff to male.
On the Walney Offshore Wind Farm project Batt At Sea Ltd provides a crew transfer service. Originally this involved transporting crews to the site for cabling works, but now Batt At Sea is the main transport vessel for each crew change. It has worked on the wind farm at Walney for 18 months.
Batt At Sea Ltd Managing Director, Terry Batt, said: “At Batt At Sea Ltd we like to view ourselves as the official guardian of the sea and our boats burn approximately a tenth of the fuel of any wind farm vessel in existence today.
“This means our fuel consumption is considerably less than any other wind farm support vessel and as the whole concept of wind farms is to offer a reduced carbon footprint through low emissions, we’re proud that our service fits in perfectly with this operation.”