An overview of the SATH technology development in the current Floating Offshore Wind Market by Sophie Davies - Renewable Energy Monitor (week 05)

1. P4 Week 05 08•February•2018w w w. N E W S B A S E . c o m
REMREM
NEW ‘swinging around twin hull’ (SATH)
technology being developed by Spain’s Saitec
Offshore Technologies will soon be competing
with other forms of floating wind systems as the
industry moves into greater depths.
With a maturing offshore wind market,
interest is now turning to floating foundations
in order to make use of wind resources further
out to sea, and in water depths greater than the
50m or so possible with fixed foundations. The
successful launch of Statoil’s 30-MW HyWind
projectlastyearhasshownthatoilandgasengi-
neering is well-poised to help the sector expand
–andhelptheoffshoreindustrydiversify–while
France’s tenders and support schemes have
attracted commercial designs from the likes of
Ideol’sFloatgenpilotandEolfi’s24-MWscheme
plannedoffGroix&Belle-Île.Otherprojectsare
underwayoffshorePortugal,theUSandTaiwan,
all using various forms of floating design.
Emblematic of this surge in interest, Saitec
Offshore Technologies, a subsidiary of Bil-
bao-based engineering company Saitec, last
month signed an agreement to develop the
SATH system in Japan in partnership with Uni-
vergy International, a Spanish-Japanese renew-
ables firm headquartered in Tokyo.
The two companies agreed to launch a spe-
cial purpose vehicle (SPV) to develop the new
technology. Saitec Offshore will contribute its
technicalknowledgeandwillconstructdemon-
strator projects, while Univergy will contribute
its experience of developing floating offshore
wind in Japan.
Concrete plans
SATH platforms are made of concrete, which
differentiates them from other floating wind
technologysolutions,SaitecOffshorechieftech-
nology officer David Carrascosa told NewsBase
Intelligence(NBI).Thecompanyisthefirstinthe
world to develop such SATH technology.
“Before concrete, steel was used – shipbuild-
ing and oil and gas companies are most used to
steel,” he said. However, “concrete behaves in a
really good manner in sea conditions. All har-
bours around the world are built out of concrete
so it is a material that is well proven and optimal
for the sea environment,” he added.
“With the use of concrete we are providing
a solution that is really cost-effective,” he said,
mainly as a result of the lower maintenance
requirementsnecessarywithconcretestructures
in an offshore environment, compared to steel.
The platforms also make use of a single point
mooring (SPM) approach, which is commonly
employed in the oil and gas industry. The struc-
ture’s twin hulls are bonded to a single point,
with a bearing that allows the platform to swing
around it. The design serves to reduce pressure
on the platform, according to Saitec.
“We are quite disruptive to the floating wind
industry because of the shape of our floater, its
mooring system and the precast construction
process,” Carrascosa said.
“With our technology you can reduce the
marine operations a lot, you also reduce the risk
for the project and the cost. The manufacturing
and assembly of the floater and wind turbine
is completely carried out onshore and then
launchedusingadry-dockorshiplift,”headded.
The construction of SATH platforms takes
place in a precast yard using methods that are
typically used in the naval industry, Saitec said.
All platform and turbine equipment is also
installed onshore – a far easier and cheaper task
than combining the two on an offshore con-
struction vessel.
A standard tugboat is then used to transport
theplatformtoitsfinallocation,wheremooring
lines and cables connect up the whole system –
very much a case of “plug and play.” The result is
thateachturbineshouldbegintoworkassoonas
it is connected, lowering installation costs “dra-
matically”, according to Saitec.
That most of the construction process takes
place onshore keeps offshore operations to the
minimum, also lowering costs, the Spanish
firm said.
Heading for open water
The company, which was founded in 2016, is
currently developing an open-sea demonstra-
tion project of SATH technology in a test centre
W H AT:
New SATH technology
could unlock new
offshore wind
developments.
W H Y:
Fabrication is faster and
cheaper onshore, while
the floating concrete
platform is easier to
maintain that steel.
W H AT N E X T:
Saitec and Univergy are
to develop the system in
Japan, with plans to build
800 MW of floating SATH
capacity.
SATH blows in change for
floating offshore wind
Sophie Davies reports on a new floating wind platform featuring twin hulls and
single point mooring being developed by Saitec. Under a new partnership with
Univergy, the technology could be used to support 800 MW of new capacity off Japan
C O M M E N TA RY
GLOBAL
The SATH floating
system.
We are quite
disruptive to the
floating wind
industry because
of the shape of
our floater, its
mooring system
and the precast
construction
process,
DavidCarrascosa
CTO
SaitecOffshore

2. P5Week 05 08•February•2018 w w w. N E W S B A S E . c o m
REMREM
offshoreBilbao,inthesouthoftheBayofBiscay,
Carrascosa said. The project will consist of one
2-MWwindturbineandwillbelocatedinwater
depths of between around 85 and 90 metres.
The project, which will be funded by a capi-
tal increase as well as by research and develop-
ment grants, will test the technology in rough
sea conditions. All the necessary permits and
licences are likely to be awarded over the next
few months and construction of the demon-
stration project is expected to begin next year,
Carrascosa told NBI.
Thisissupportedbyarecentlycompletedtest
campaign, designed as a precursor to the open-
sea demonstration project, at an environmental
hydraulics research centre at Cantabria Univer-
sity in the Spanish city of Santander. Waves, cur-
rentsandwindconditionsweresimulatedduring
thetest,includingturbulentwindconditions.
While tests are ongoing, the company is very
muchinthe“fullcommercialdeploymentstage,”
saidCarrascosa.“WeareworkinginTaiwantry-
ing to implement the technology in commercial
farms that will be deployed soon,” he added.
Following their recent agreement, Saitec
Offshore and Univergy intend to develop two
wind farms with a combined capacity of up to
800 MW in Japan, Carrascosa said, although he
noted that planning for these schemes was still
only in the preliminary stages.
The business is also being developed else-
where, including in Australia and the US, he
added. “There are a lot of countries which are
now starting to develop offshore wind – up to
now it was mainly focused in northern Europe,”
he said. The market for these technologies is
growing “very fast and globally,” and buoyed
by interest from countries without existing,
fixed-foundation offshore structures who are
keen to kick-start regional markets. “One of the
great advantages of floating technology is that
you can develop it wherever you want in the
world, wherever there is a wind source. There is
no depth limitation,” he added.
Indeed, China is now looking to establish a
footholdintheoffshoremarket,andcouldeasily
be the same size as Europe’s in terms of installed
capacity within just a few years, he said.
Taiwan in particular has been pursuing the
technology in recent years, and is currently
developing the W1N/Taoyuan project, slated
to have around 190 MW in generating capacity,
in partnership with aforementioned Eolfi. The
project is currently negotiating environmental
approval, having suffered a setback in late 2017
when navigation channels were changed, but is
scheduled for delivery in 2022.
Not without a permit
As Eolfi’s case goes to show, the speed of floater
installation is tempered by a more difficult
permitting process. Floating projects can take
a number of years to develop, in part because
it can be time-consuming to get offshore
permits, though this depends on largely the
location, according to Carrascosa. “It is usu-
ally more complicated than for onshore work
because it’s a new market and the regulation
has to be adapted – that can take some years,”
he said.
Offshorewindprojectstypicallyrequiremore
permits than onshore projects, because compa-
nies have to deal not only with the port, but also
theharbourandfishermen,forinstance,hesaid.
In that regard, he said that governments
should simplify procedures for obtaining off-
shore permits, to speed up the process of float-
ing installations. Given the nascent state of the
sector,itislikelythatreformswillcome,butper-
mittingcouldbemadeeasierforpilotprojectsin
order to qualify the technology faster.
This is but one challenge that Saitec Off-
shore will face in its lengthy development
phase. Yet given the advantages offshore by
SATH and other floating systems, this is cer-
tainly the direction the offshore industry is
heading. With a fair wind, their commercial
arrival will not be long.v
C O M M E N TA RY
Saitec’s SATH design
uses a single-point
mooring system and a
concrete structure to
minimise maintenance
offshore.
Source: Saitec