INTEGRATED CABLE SOLUTIONS
FOR OFFSHORE WIND DEVELOPMENT
OFFSHORE WIND BRINGS NEW OPPORTUNITIES
Offshore wind is one of the most stable New trends and drivers
sources of renewable energy. Power • Increased cost-competitiveness: Offshore wind power
fluctuations are minimal due to prevalent is still expensive. As a viable solution, production costs
ocean wind patterns. And the need for must be reduced both in terms of hardware (wind
standby generator capacity for peak load turbines), control software, and cable infrastructure.
servicing is largely eliminated through
• Larger and more efficient turbines: Higher energy
accurate weather forecasting combined with
capture, increased reliability and lower operating costs
remote databased control and management.
can generate 9 % savings per unit. Next-generation 6-8
This reduces costs, enhances network
MW turbines require durable, large capacity cables.
stability, and contributes to a balanced
“clean” power supply. •D
eeper waters farther out to sea: Offshore towers and
infrastructure must be able to handle severe ocean
In the coming years, offshore wind could triple capacity,
conditions. Cables and components need to be salt-
from 8 GW today to 24 GW by 2020, thus becoming
and water-resistant and display dynamic maritime
a trustworthy renewable resource for Europe’s integrated
qualities.
supergrids of the future. Indeed, offshore wind will play
a key role in “keeping global warming below 2° C,” the •U
pgraded transmission and interconnection
goal of the 2015 COP21 Conference held in Paris. infrastructure: Ocean-based turbines, whether fullscale
floating devices or grounded on the seabed, require
Recent offshore wind trends include a move towards
appropriate infrastructure to export energy to land-based
larger turbines and deep-water floating units. Offshore
grids, and provide telecommunications for remote
projects (up to 200 km from shore) require robust cables, control.
precision maritime installation, and efficient long-distance
• Improved supply chain, logistics and installation:
transmission, involving innovative cable solutions and Optimization could potentially achieve 3 % savings.
reliable accessories. This demands cable and accessories availability, as
well as onsite delivery and installation using specialized
cable laying vessels. This requires marine proficiency
and cable-laying capability.
• P artnerships and trans-regional cooperation: This
is especially crucial in research, technological
development and training. International projects require
specialized cable expertise, shared knowhow, and
adherence to world standards.
INTEGRATING CABLES AND
POWER ACCESSORIES IN TOUGH SEA CONDITIONS
Nexans has the expertise to outfit large
offshore wind turbines, interconnect them
in complete windfarms, and link them to
distant or local or grids. For medium and
high-voltage cables, we oversee complete
installation, from initial pre-qualification,
design, customized production, logistics,
installation, testing and pre-commissioning.
This includes all accessories, a key element in
any efficient energy network.
We supply and lay MV subsea cables between wind
turbines and the transformer platform, and the MV or HV
link to the onshore substation. We also provide power
accessories and topside termination on wind turbines
and transformer platforms. At the same time, we have
been developing cables and power accessories for those
OEMs producing a new generation of stationary and
floating turbines.
Apart from a full range of energy cables and services,
Nexans are also experts in the telecommunications
infrastructure needed to manage offshore wind parks,
including control and data cables, copper and fiber Local
Area Networks.
Innovative technologies
• World supplier of submarine and underground cables,
overhead conductors and data/telecom systems
• Close partnership with developers, power utilities,
installers and contractors
• Mastery of maritime conditions based on oil & gas
submarine energy and telecom cabling experience
• Unsurpassed offshore installation and topside
termination experience using advanced equipment,
special software for overhead lines, and dynamic cable
solutions
• Complete range of power accessories: separable
connectors, cold-shrinkable and heat-shrinkable joints
and terminations for various types of cable
• A wide range of aluminum based solutions, mechanical
connectors, cable lugs and pre-manufactured cable
kits for offshore wind turbine manufacturers, ensuring
reliable aluminum to copper connectivity
• System solutions in the transition piece where junction
frames or cabinets assure the link between an inter
array cable and the switch in the basement of a tower.
This ensures easy and effective mounting and a clear
responsibility border during build-up of the tower
WINDLINK® RELIABLE SOLUTIONS FOR WIND TURBINES
Our WINDLINK® offer proposes a full range of reliable, high-performance cable solutions for
wind turbines. WINDLINK® contributes to improve wind turbine output and performance and
comprises solutions for both towers and nacelles. Our fully tested electrical systems and easy-
to-install kits considerably reduce installation times. Some of the main product families include:
Low-voltage loop rubber cables Low-voltage fixed installation cables
• These cables (up to 1 kV) reliably transmit energy • Copper can be single or multicore, with EMC
produced in the generator to the transformer, usually screening.
located at the base of the tower. • Aluminum singlecore are larger; they weigh half
• They come in Low-Smoke Zero-Halogen (LSZH) versions, as much, making them cheaper, and easier to handle and
and are also oil-, abrasion-, UV- and ozone resistant. install in high towers.
> Whenever we supply this cable we do lifetime tests > Nexans has supplied a wide range of LV installation
according to movement and torsion requirements. cables to Alstom Wind, Nordex, Siemens, Vestas,
GE, etc.
Medium-voltage loop rubber cables
Low-voltage loop aluminum cables
and accessories
• Innovative cable design to allow torsion requirements
due to nacelle rotation.
• 150 mm2 to 400 mm2 aluminum replaces 95 mm2 to
240 mm2 copper.
• Mechanical connectors with shear-off-head bolts tolerate
different conductor cross-sections. The force of the screw
creates electrical contact between the conductor and
connector body.
• Factory pre-installed solutions, including cables, lugs
and connectors.
• Similar to LV loop cables, they can handle up to 66 kV
between the nacelle-based transformer and the switchgear
at the base.
> We are supplying MV loop cables in 3+1 core or 3+3
core designs to all the biggest WTG manufacturers using
this solution.
A full range of WINDLINK® rubber cables.
IMPROVING POWER OUTPUT AND PERFORMANCE
Low-voltage joints Low-voltage kits
• Able to withstand thermal • To facilitate assembly,
cycling and tower vibration Nexans provides pre-
throughout a turbine’s terminated kits which bundle
lifetime, our systems use a energy, control and data
mechanical shear-off-head cables for wind turbine
bolt connector with an electronics.
innovative rubber sleeve. •Also, cut-to-length, pre-
• A new connector made of high-strength aluminum alloy connectorized, all-power cables are supplied to tower
(copper to aluminum) with a protective roll-on sleeve is fast manufacturers for generator-to-switchgear-to-main-
and easy to install without special tools. powerline links.
> Roll-on sleeves offer protection, insulation, shortcircuit > Nordex appreciates the consolidation of several cable
stability and long-term reliability. types into a single purchase.
Medium-voltage connectors
• Nexans safe-to-touch
T-shaped standard outer
cone connectors are
designed for the new
generation of compact
switchgears and
transformers.
• Power accessories can also accommodate larger cross-
sections up to 1 200 mm² of large turbines and cable-
to-cable connections up to 42 kV, all in an outer cone
version.
> The compact design makes it easy to connect to the
transformer’s three phases without female units.
BUILDING OPTIMAL WINDFARM INFRASTRUCTURE
Medium-voltage cables
• Cost-efficient submarine 66 kV Inter-array Cables
3-core cables with integrated The trend towards increasingly
fiber optic elements and powerful wind turbines requires
customized armor designs. different array cabling.
> We provided inter-turbine/ Compared to 36 kV, the higher
export cables for Anholt (DK), voltage 66 kV cables and associated
the world’s third largest offshore wind farm. connectors allow the familiar offshore
layout to be maintained, with strings
High-voltage cables for transmission of four to five (or more) wind turbines
• Offshore AC transmission: standing in a row. These cables
submarine cables ranging from allow for greater power capacity
60 kV to 500 kV with various with smaller cross section and lower current, and do
designs available: 3-core XLPE not require additional transformer stations.
cables (60−225 kV); single They also offer cost savings through lower life-
core XLPE up to 400 kV. cycle costs and optimized intra-array cable layout.
• Offshore DC transmission up to 525 kV applicable Ultimately it will drive greater capacity in offshore
for high transmission requirements and long distances: wind. The next objective is to develop and qualify
mass-impregnated cables with Integrated Return a 66 kV subsea cable with a solid aluminium
Conductor, and Polymer-based insulated DC cables conductor, in order to meet and anticipate customer
> For the London Array offshore windfarm, we developed, demand.
produced and delivered four 55 km 150 kV XLPE
submarine cables with fiber elements for communication
and temperature monitoring being laid in parallel to the 66 kV Power Accessories
substations. With the development of the 66
kV inter-array cable, the full range
of bushings, connectors, surge
arresters, terminations, joints and
special alloy contacts for large
cross-sections were developed. The
connectors are based on the outer
cone standard and the piggy-back principle. Besides
the easy mounting conditions of a plug-in connector,
they are also easy to use in an environment of 2 or
more cables for one phase. Surge arresters can be
plugged into the connector.
220 kV Export Cables
The choice of a 220 kV export cable between the
windfarm and the grid is based on the evolution of
several aspects :
• offshore substation technology is changing
• cable transmission capacity
• turbines are becoming larger
• windfarms are increasingly bigger
In Europe, 400 - 600 MW windfarms are being built
further offshore, requiring higher voltages : 220 kV
cables are optimum both technically and cost-wise
when considering the total cost of the system.
MV accessories designed to reduce Installation services: C/S Nexans Skagerrak
installation time Topographical surveys,
design and engineering are
done
in close cooperation
with the customer. Actual
installation involves project
management and carefully
planned logistics. Long after
commissioning and testing,
we are still there to train personnel and intervene rapidly
in case of system failure.
> C/S Nexans Skagerrak was the first purpose-built
vessel for transport and laying of large submarine power
• A range of offshore junction cabinets (OJC) or frames cables. She has a unique service record covering
(OJF) for use in the transition piece of turbine towers and installation of cables and umbilicals including some of the
in substations. Pre-terminated leads offer important cost world’s largest power cables. Developments in the laying
savings. of long and heavy submarine cables at greater depths,
• For offshore, an OJC can be used as a connection have made it necessary to employ larger and more
point between tower cables and subsea array cables. specialised transport and laying vessels built especially for
that purpose.
• Cabinets and frames can also be used in offshore
substation solutions. Installation services: Capjet® System
> Our terminations and joints make installation quick, The CAPJET® system was
easy and long lasting. Specific training courses in power developed as a diver-
accessories installation are available. operated system in 1976,
and acquired by Nexans
Auxiliary equipment and systems
in 1987. The Capjet®
Mechanical support (hang- 1MW system, using a 1.1
off and clamping systems, MW underwater power
protective shells ⁄ slabs ⁄ supply, was developed in
mattresses). 1991. The system has been
> Easy-to-install hang-offs to subsequently enhanced with special features for flexible
fasten energy cables above and steel pipelines, umbilicals and power cables, seismic
sea level, available sealed cables and rock-cutting modules, as well as equipment
or non-sealed. for covering and surveying for final documentation
(pipetracker, multibeam etc.).
NEXANS’ PRESENCE IN MAJOR WINDFARMS
At the end of 2014, the installed capacity in Europe was about 8 GW. Nexans is present with
cable solutions in approx. 50% of these windfarms, and plans to further develop this business
to extend its presence with ever higher performing cable solutions.
Beatrice
BEATRICE OFFSHORE
WINDFARM LTD
588 MW
220 kV
260 km (offshore + onshore)
Walney Extension
DONG
200 MW
34 kV
190 km
West of Duddon Sands
DONG
389 MW
34 kV
123 km
Barrow
DONG
90 MW
132 kV XLPE AC
27 km
Arklow
GE WIND
25 MW
33 kV XLPE AC
20 km
Burbo Bank
DONG
210 MW
34 kV XLPE AC
56 km
Westermost Rough
DONG
210 MW
34 kV
53 km
Lynn and Inner Dowsing Lincs Sheringham Shoal London Array
CENTRICA CENTRICA STATOIL DONG
100 MW + 100 MW 270 MW 317 MW 630 MW
33 kV XLPE AC 132 kV + 33 kV XLPE AC 132 kV + 33 kV XLPE AC 150 kV XLPE AC
6 x 8 km + 40 km 2x50 km + 80 km 2 x 20 km + 80 km 4 x 53 km
Hywind (floating)
STATOIL
2,3 MW
24 kV XLPE AC
12 km dynamic
Anholt
DONG
400 MW
34 kV
160 km
Arkona Südost
e.on
400 MW
33 kV XLPE AC
77 kmm
Horns Rev 1
DONG
160 MW
150 kV + 33 kV kV XLPE AC
42 km
Horns Rev 2
DONG
210 MW
150 kV + 33 kV XLPE AC
42 km
Borkum Riffgrund 1&2
DONG
312 MW + 450 MW
34 kV
81 km + 105 km
Riffgat
ENOVA / EWE
115 MW
33 kV XLPE AC
24 km
Belwind Northwind Gode Wind 1&2
VAN OORD NORTHWIND N.V. DONG
165 MW 216 MW 330 MW + 252 MW
152 kV XLPE AC 220 kV XLPE AC 34 kV
52 km 57 km 134 km
Aucune mention n’est faite de droits relatifs à des marques ou noms commerciaux, qu’ils soient enregistrés ou non, et qui peuvent être attachés à certains mots ou signes utilisés ici. Cependant, l’absence d’une telle mention n’implique
Création/réalisation : O’communication - 09/2016. Crédits photographiques : Fotolia - Suhutterstock - Thinkstock - Nexans
Nexans brings energy to life through an extensive range of cables and cabling solutions that
en aucun cas que ces marques, noms commerciaux, mots ou signes ne bénéficient pas d’une protection.
deliver increased performance for our customers worldwide. Nexans’ teams are committed to
a partnership approach that supports customers in four main business areas: Power transmission
and distribution (submarine and land), Energy resources (Oil & Gas, Mining and Renewables),
Transportation (Road, Rail, Air, Sea) and Building (Commercial, Residential and Data Centers).
Nexans’ strategy is founded on continuous innovation in products, solutions and services, employee
development, customer training and the introduction of safe, low-environmental-impact industrial
processes. In 2013, Nexans became the first cable player to create a Foundation to introduce
sustained initiatives for access to energy for disadvantaged communities worldwide. Nexans is
an active member of Europacable, the European Association of Wire & Cable Manufacturers,
and a signatory of the Europacable Industry Charter. The Charter expresses its members’ commit-
ment to the principles and objectives of developing ethical, sustainable and high-quality cables.
We have an industrial presence in 40 countries and commercial activities worldwide, employing
close to 26,000 people and generating sales in 2015 of 6.2 billion euros. Nexans is listed on
NYSE Euronext Paris, compartment A.
Nexans
8, rue du Général Foy - 75008 Paris - France
Tel. : +33 (0)1 73 23 84 00 - Fax : +33 (0)1 73 23 86 38
www.nexans.com/windfarms
marcom.info@nexans.com
