Brochure - GICON® - SOF

Bioenergie GmbH
GICON® - SOF
A modular TLP Solution for a swimming world

THE GICON® SOF
THE BEST TLP SOLUTION
Offshore wind power is one of the most important
backbones of a sustainable energy supply. Current
construction of classic offshore wind turbines is,
however, associated with enormous technical, environmental
and financial challenges. It is therefore
crucial for the offshore wind industry to minimize
these costs and risks. Another question of vital significance
for the industry is the development of projects
in deeper water with high wind yields. Approximately
75% of the global offshore wind potential
is located in areas with water depths greater than
30 meters; at least two-thirds are in water depths
greater than 50 meters.
Generelles
The GICON®-SOF floating offshore substructure
provides an ideal solution for these challenges.
GICON’s SOF development provides a floating
substructure for offshore wind turbines which can
be deployed in water depths of 45 to 350 meters
and more while achieving LCOE (Levelized Cost of
Energy) of 5 to 8 € cent / kWh. This makes GICON
one of the global development leaders for floating
offshore wind substructures. The R&D project started
in 2009 and includes renowned partners such
as TU Bergakademie Freiberg (Freiberg Technical
University and Mining Academy), Rostock University
and Fraunhofer IWES. Thanks to the continous
improvements based on results from research like
extensive wind & wave tank tests, the GICON®-SOF
is ready to prove its capacities in a full scale multi-megawatt
prototype.
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THE GICON® SOF
THE DEVELOPMENT
The development of the GICON®-SOF is beeing pushed forward since almost a decade. The illustration
below shows the evolution of the technology since 2009 (left-hand side) until today
(right-hand side). In the beginning the SOF was based on a latticed strcuture. A latticed structure
benefits from several advantages but high amount of connection makes the manufacturing
process very complicated and expensive. In 2015 the loverable gravity foundation was introduced,
greatly enabling the eased one-step installation.
The latest results from economic considerations and technical innovations helped to accelerate
the progress. Different computational simulations as well as wave and wind tank tests where
carried out. The videos below show different tank tests during different states of development.
Furthermore an animation shows the fast and easy assembling of the GICON®-SOF in a dry-dock
and its installation using standard tug-boats.
2009
2012 2013 2014 2015 2017
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THE GICON® SOF
THE CONCEPT OF CHOICE
As a tension-leg-platform (TLP) the GICON®-SOF has significant advantages compared
to other floating substructure types like semi-submersibles or spar buoys. The semi-sub
gains its stability from its outer dimensions, activating the water plane area to compensate
the overturning moment caused by the turbine thrust. Thus, to support a 6 to 10 MW
turbine a semi-sub would have huge outer dimension. This heavily decreases the number
of possible manufacturing sites.
In contrast, a spar type floater is very slender but it needs a very great draught (~100m)
to stabilize a 6 MW turbine. This makes manufacturing and transport & installation (T&I)
in particular very difficult. Contrary to semi-subs and spars where catenary moorings are
used, a TLP is attached to the seabed with taut mooring lines. The structure‘s buoyancy
which is much greater than its weight is causing a strong upward directed force. By tensioning
the moorings the entire structure becomes firmly braced, which causes a very stiff
system resisting even the strongest weather conditions with minimum accelerations and
deflections. Due to its inherent stability a TLP can be designed much smaller compared to
a semi-sub or a spar.
GICON and its research partners have been developing the GICON®-SOF since 2009. In this
process three key issues were identified that led to high costs. To tackle these issues an
improved manufacturing and installation concept was developed to drastically reduce the

THE GICON® SOF
MODULARITY
Shipyard and dry-dock rent are important cost factors. These can be minimized by prefabricating
the components and transporting them to a harbour close to the commissioning
site. This leads to a drastically reduction of the building time and therefore short occupancy
of the dry-dock. In addition prefabricating means a great flexibility with regard to the supply
chain, as well as for possible assembly sites. Introducing prefabrication also makes the
entire construction process less demanding on the site where it is carried out. Furthermore,
the assembly of the GICON®-SOF does not rely on a dry- dock. It is also possible to be carried
out on a floating pontoon or just a flat area of the harbour using a shiplift for the launch.

THE GICON® SOF
NEW MATERIALS - LESS COSTS
99% of current offshore structures are conventionally build by welding elements of shipbuilding
steel. However, welding operations are very time consuming and expensive. For
one single steel floating substructure for a 6 MW turbine at least four months of working
would be necessary. When considering man hours, rent for the dock and raw materials, this
floating substructure would cost 2500-3000 € per metric ton. For the GICON®-SOF instead,
prestressed ultra-high performance concrete (UHPC) elements will be used, which leads to
a significant reduction in production cost.
For the GICON®-SOF instead, prestressed Ultra-High-Performance-Concrete
(UHPC) pipes will be used. UHPC has a very high density and therefore
high bearing capacities. This means the GICON®-SOF can be build
more efficiently which leads to lighter designs. Prestressing is a proven
method in bridge engineering. By this approach a prestressing force is
applied to the concrete element, causing a high compression within
the concrete matrix. This ensures, that during the entire lifetime of the
structure, no tensile stresses occur within the concrete material. As concrete
can bear very high compression but only very low tensile stresses
prestressing is a great method to improve the bearing capacity and life
time of members made from this material. The prefabricated concrete
elements have a cost of 450-500€ per metric ton which is much more
cost efficient than welded steel structures.
The buoyancy bodies, which are placed at the 4 corners of the GI-
CON®-SOF, are made out of concrete shell elements. These elements
are well known and have been proven in tunnel engineering over decades
where they are designed to last at least 100 years. This includes
also the sealing which can bear mountain water pressures of more than
1*10⁶Pa.

THE GICON® SOF
ECONOMICS
Higher revenues
Operation of offshore wind turbines in higher wind resource areas with water depths from 45 to
350 meter and more, utilizing the GICON®-SOF, generates higher revenues compared to offshore
wind turbines on conventional bottom fixed foundations.
K f
K = K v
+ K f
Fixed costs
k f
Fixed unit costs
Reduced fabrication costs
One standardized substructure design can be utilized for an entire offshore wind park project.
Differences in water depth within a site are compensated by adjusted cable lengths while the
SOF substructure design and dimensions are the same for each turbine installed at the site.
At the same time, the paradigm shift from usual welded steel designs towards more efficient
and innovative technologies based on prestressed ultra-high-performance-concrete and casted
iron members enables significant advantages for cost savings.
Reduced installation costs and installations risks
Substructure fabrication and turbine assembly happen completely at shore, independent from
weather windows. The entire platform including turbine is then towed to the offshore deployment
site. Successfully conducted tank tests with a scale model suggest a towing speed of up
to 5 KN at 2.5 meter swells. Expensive installation vessels or jack-up platforms are therefore not
required. Decommissioning at the end of the operational lifecycle is also less costly and less
complicated. Flexibility regarding the use of different anchor types also results in less demands
on suitable subsoil.
Reduction of maintenance costs
If required, the entire substructure, including tower and turbine, can be replaced. Major maintenance
work can be handled at shore.
LCOE in Euro (€) cent of 5 to 8 € cent/kWh
An independent consulting group determined a Levelized Cost of Energy (LCOE) of 5 to 8 €
cent/kWh for a scenario where the GICON®-SOF is utilized in a wind park consisting of 80 6MW
turbines, in 80 meter water depth and at 50 km distance from shore. Deployment in deeper
water and additional optimization potential is likely to further reduce this LCOE assessment.
K v
K
Fixed costs are independent of the employment/utilization.
E.g. Rent, Interest, etc.
Variable costs
Variable costs are independent of utilization.
E.g. Material and manufacturing wages
Total cost
m
m
K v
K f
m
k v
k
Variable unit costs
Total cost per unit
m
m
k f
k v
m
k =
K v
+ K f
m m
Law of Mass
Production
k = k v
+ k f
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THE GICON® SOF
USE WORLDWIDE
Offshore wind energy will be a major pillar of renewable energy worldwide. Since 60 - 80% of the global
offshore potential is located in water depths > 50 m, current foundation concepts such as monopile and
jackets are inappropriate for the continued development of this energy sector. Floating foundation concepts
have great potential to address this deficit.
Waterdepths 45m - 350 m

THE GICON® SOF
ASSEMBLING AND INSTALLATION
All prefabricated part of the GICON SOF will be taken to the port in the country.
At the harbour side all components are going to be assembled together with the gravity
anchor and put into water. Eithervia ship crane, flooding by dry dock or on a on a pondon.
GICON® SOF will be towed to its final berth with two days.
Final installation of all cables and lowering the gravity anchor to the sea bed.
8 TLPs in 2 weeks - 200 TLPs per year in one dry dock

THE GICON® SOF
OVERVIEW OF WORLDWIDE PATENTS
Schwimmfähiger Schwergewichtsanker zur
Verankerung eines in der offenen See schwimmenden
Tragwerks mit einer Windkraftanlage,
Servicestation oder Konverterstation
Autark schwimmfähige Schwergewichtsgründung
zur Verbindung einer schwimmfähigen
Offshore-Anlage
Schwimmfähige Offshore-Anlage zur Umwandlung
von Windenergie und/oder Sonnenenergie
in elektrische Energie
Offshore-Windkraftanlage zur Umwandlung
von Windenergie in elektrische Energie
Europa
Patente
Schwimmendes Gründungstragwerk
mit Auftriebskomponenten
in aufgelöster Bauweise
Schwimmfundament mit verbesserter
Abspannung
Schwimmendes Offshore-Fundament und
Verfahren zu dessen Herstellung
(EP Anmeldung, steht vor Erteilung)
In der offenen See schwimmendes und über
Abspannmittel mit Ankern verbundenes Tragwerk
für Windkraftanlagen, Servicestationen
oder Konverterstationen
Verankerungsstabilisierte Trägerboje
Tiefgründungspfahl für Offshore-Bauwerke
mit beim Eintreiben schallreduzierender
Wirkung
Patent erteilt
Patent noch nicht erteilt

THE GICON® SOF
SUCCESSFULLY TESTED
Wave- and Windtests
Year: 2017
Location:
Laboratory in Hydrodynamics, Energy and Atmospheric Environment of
Central Nantes/CNRS (France)
Subject of the test:
In ECN‘s water basin, waves with significant wave heights of 11.4 and
12.9 m were simulated, as such waves only occur statistically every 10 and
50 years, respectively.
Transport- and Installationtests
Year: 2018
Location:
SSPA Maritime Dynamics Laboratory in Gothenburg (Sweden)
Subject of the test:
tests included the towing of the SOF using the buoyancy of the gravity
anchor plate, the lowering of the gravity anchor plate and the pulling
down of the SOF under smooth water conditions.
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THE GICON® SOF
R&D PARTNERS

Großmann Ingenieur Consult GmbH
GICON Group
Tiergartenstraße 48 I 01219 Dresden, Germany I T +49 351 47878-0 I F +49 351 47878-78 I info@gicon.de
www.gicon.de