Viterbo's Analyses on the competitiveness of ofshore wind energy for Brazil.

1. 1 / 58
Notes on Offshore Wind Energy
Dept. Ocean Eng. & Naval Architecture
Polytechnical School
University of São Paulo
Jean CarloViterbo, M.Sc.
11/11/2019

2. 2 / 58 Greenhouse Effect (I - present)
Source: US - EPA
FROM WHICH ACTIVITIES (TODAY) ? WHERE DOES IT COME FROM (TODAY)?
HOW DOES IT HAPPEN (TODAY) ?

3. 3 / 58 Greenhouse Effect (II - past)
World Resources Institute (WRI) (2011), Climate
Analysis Indicators Tool (CAIT): Indicators: GHG
Emissions: Cumulative Emissions (free registration
required), Washington DC
Cumulative energy-related CO2 emitters
between 1850–2008
WHERE DID IT COME FROM ...
CONSIDERING THE INDUSTRIAL ERA ?
COMO SE ORIGINA NO HISTÓRICO CURTO DO PAÍS QUE É
O PRINCIPAL RESPONSÁVEL AO LONGO DA HISTÓRIA?
1990–2010

4. 4 / 58 Greenhouse Effect (III - sectors)
World Resources Institute (WRI) (2011), Climate
Analysis Indicators Tool (CAIT): Indicators: GHG
Emissions: Cumulative Emissions (free registration
required), Washington DC
Cumulative energy-related CO2 emitters
between 1850–2008
WHERE DID IT COME FROM ...
CONSIDERING THE INDUSTRIAL ERA ?
ACHIEVEMENT IN WORLD’S LARGEST ECONOMY,
LARGEST ACCUMULATED EMITTER
1990–2010

5. 5 / 58 Greenhouse Effect (IV - US pathway)
US GHG EMISSIONS IN 2017 WERE 1,35%
LARGER THAN 1990
US GDP IN 2017 WAS 92,75%
LARGER THAN 1990
US POWER GEN 2017 WAS 32,78%
LARGER THAN 1990
Along the digital era, energy (and
electricity) is loosing its (once
excessive) weight within US GDP.
The US prefered to reduce its
emissions replacing coal by NG,
far more than by renewables.
2018
17%
12%
12% 35%
200 gCO2/kWh (43% less than coal)
350 gCO2/kWh

6. 6 / 58 (Un-)Evolution of the World Power Matrix (IEA)
Rio 92
From 1992 to 2017, 13.500 TWh (25.600 –
12.100) were added to the anual world supply. In
that meanwhile, 9.600 TWh, more than 70% of
the new power annualy supplied, is fossil.
SINCE THE FIRST OIL CRISIS (1973)...
Oil dropped 21.5pp, turned marginal in power
gen. Hydro dropped 5pp. The 26.5pp drop-down
was replaced by raisings in Natural Gas (11pp),
Nuclear (7pp) and Other Renewables (8.5pp).
Coal remained stable,~40% of world power
supply.
Fossil 2017 was 16.597 TWh
Fossil
power
added
since
RIO 92
~9,600
TWh
“N” “H” “R”
NHR
added
since
RIO 92
~4,100
TWh
NHR @ RIO 92

7. 7 / 58
Pollution caused by the traditional generation has several effects, such as crop failure,
damage to the health of the population and public property. The values resulting from these
effects are not internalized in the energy tariff, but paid by the social macrosystem.
“Externality” is the amount of compensation value that should integrate the cost of energy
from a certain source, according to the magnitude of the damage it causes.
Projeto “Extern E” UE 15
Externalities (2004)
0 10 20 30 40 50 60 70 80 90 100 110 120
Dinamarca
Espanha
Alemanha
Dinamarca
Espanha
Alemanha
Dinamarca custo interno
custo externo mínimo
custo externo máximo
Natural Gas
Wind
Coal
Source: EWEA 2004 and
The European Comission
(€ /MWh)

8. 8 / 58 Externalities (2014) Source: EcoFys 2014 and
The European Comission

9. 9 / 58 Evolution of the Global Wind Capacity (GWEC)
Accumulated
Capacity
New installations
by year
Offshore boosted
in 2017 and 2018

10. 10 / 58 Comparativos das quedas de custo das tecnologias
Curvas de aprendizagem de fontes energéticas: etanol
(Goldemberg et al., 2004), fotovoltaica (Parente, Zilles,
Goldemberg, 2002), eólica (Neij et al., 2003), e gás
natural de ciclo combinado (Colpier, Coland, 2002)
Custos da geração em função do investimento e dos
ventos locais (site da Assoc. Européia de Energia Eólica)
Resultados mais recentes da curva de
aprendizagem eolica p/ usinas onshore do RU
(€1050/kW 2001) e Espanha (€830/kW 2001).
*RP = Razão de Progressão, é o novo patamar de
custo que uma tecnologia assume qdo sua base
mundial dobra
US$ 2.350 /kW
US$ 1.900 /kW
US$ 1.500 /kW
US$ 1.050 /kW
Fev 2013
1€ = US$ 1,31
R$ 312
R$ 260
R$ 208
R$ 156
R$ 104
R$ 52

11. 11 / 58 Experience Curves (or Learning Curves)
BNEF: Bloomberg New Energy Finance
WTMR: US DoE Wind Tech Market Report
Wind Turbine prices (25%) have
decreased faster than PV Systems (18%),
even though

12. 12 / 58 Cost of Energy
127
US$/MWh
56 US$/MWh
Source: IRENA Ren Costs Report 2018

13. 13 / 58 Improvements on Efficiency PV x OnW
PV
OnW
Source: IRENA
Ren Costs Report 2018

14. 14 / 58 Improvements on Efficiency OnW x OfW (IRENA 2018)
Source: IRENA
Ren Costs Report 2018
OfW
OnW

15. 15 / 58 OffshoreWind - Farther and Deeper
Source: IRENA
Ren Costs Report 2018
Water depths between 10 m
and 55 m and up to 90 km
offshore, compared to around
10 m water-depth in 2001–
2006, when distances to port
rarely exceeded 20 km.

16. 16 / 58 OffshoreWind - Larger
Source: IRENA
Ren Costs Report 2018

17. 17 / 58 OffshoreWind - Farther and Deeper
Source: IRENA
Ren Costs Report 2018
From an average of around USD
2 500/kW in 2000 to around USD
5 400/kW by 2011–2014, before
falling to around USD 4 350/kW in
2018. Total costs are higher in
Europe than in China, reflecting the
fact that Chinese deployment to
date remains in shallow waters,
close to ports.

18. 18 / 58 OffshoreWind – Not cheaper yet
Source: IRENA
Ren Costs Report 2018
The global weighted-average LCOE
of projects commissioned in 2018
was USD 0.127/kWh. Like
total installed costs, the average
LCOE increased up to around
2011, before declining noticeably
between 2016 and 2018. The
weighted average LCOE was
around USD 0.134/kWh in Europe
in 2018. This was 28% higher than
in China, where the value was
around USD 0.105/kWh.
Levelized Cost of Energy – LCOE
LCOE =

19. 19 / 58 OffshoreWind - Farther and Deeper
Source: IRENA
Ren Costs Report 2018
Capacity factors are higher in
Europe (38% to 50% in 2018) than
in China (23 to 34%), reflecting the
relatively poorer wind resource and
smaller turbines for near-shore
Chinese projects. A clear trend to
higher capacity factors for
new offshore European wind farms
can be seen since 2008, with
average capacity factors rising from
an average of around 35% to
around 50% in 2017 and 2018.

20. 20 / 58 OffshoreWind – Capacity Factor seems to be the way
Source: IRENA
Ren Costs Report 2018
The capacity factor of
new onshore wind
projects increased from
20% in 1983 to 34% in
2018, and from 26% in
1991 to between 43%
and 47% in 2018 and
2017 for offshore wind.
The gap between
onshore and offshore
capacity factors has
narrowed since 2015 as
onshore wind capacity
factors have surged.

21. 21 / 58 Brazil – Highest Capacity Factor for OnW (coast line)
Source: IRENA
Ren Costs Report 2018

22. 22 / 58 Forecasts for the Global Power Matrix
McKinsey: Global Energy
Perspective 2019
DNV, Germanisher Lloyd, 2019
Renewables Forecast to 2050
! !

23. 23 / 58 Forecasts for the Global Power Matrix
DNV, Germanisher Lloyd, 2019
Renewables Forecast to 2050
US DoE
Offshore Wind
Technologies
Market Report
2018
? ?

24. 24 / 58 Forecasts for the European Power Matrix
Bigger turbines, technology learning and low
financing costs are driving down costs of new
projects. Policy frameworks enabling low-cost
financing are essential to drive offshore wind
towards competitiveness.

25. 25 / 58 Forecasts for the Global Power Matrix

26. 26 / 58 Forecasts for the Global Power Matrix

27. 27 / 58

28. 28 / 58

29. 29 / 58
Maior dispersão (6 MW/km2 offshore x 13 MW/km2 onshore)
Redução do “efeito sombra” dentre turbinas
Menor restrição de ruído
permite maior velocidade rotacional
permite gerador de maior tensão para um dado rotor
permite geração em DC
dispensa uso de conversores
redução da perda elétrica
maior eficiência de absorção energética
menor torque menor massa
maior
fator de
capacidade
- custo das pás
REDUÇÃO DE
CU$TO$
- custo do sistema elétrico
- custo da torre
- custo da
energia
- custo da
energia
Exemplo de efeitos sistêmicos da versão Offshore
Musial, W.; Butterfield S. (2004). Future for Offshore Wind Energy in the United States. To be presented at Energy Ocean
2004. Palm Beach, Florida. National Renewable Energy Laboratory, p.7.
Henderson, A. P. et al. (2003). Offshore Wind Energy in Europe – A review of the state-of-the-art. Wind Energy, No 6, p. 38.

30. 30 / 58 Trade-offs

31. 31 / 58
Fonte: NREL

32. 32 / 58 Transporte

33. 33 / 58
Fonte: NREL
Infraestrutura

34. 34 / 58 Estatísticas do Setor Eólico Offshore em 2012 (EWEA)

35. 35 / 58
Modelo NREL dos ciclos de P&D entre áreas: petróleo offshore, eólica em águas
rasas e eólica em águas profundas. (Musial e Butterfield, 2004)
Projeto daTurbina GE 10 MW, comparada
ao maior avião da atualiddade (Lyons, 2007)
DesafiosTécnicos
✓Algoritmos para predição de cargas mecânicas, pois uma a turbina terá comportamento hidrostático distinto de plat. de petróleo;
✓Design orientado para a minimizar o trabalho de instalação e operações no mar, reduzindo o custo de O&M;
✓Modelos de avaliação da interação infraestrutura-aerogerador;
✓Modelos de sensoriamento remoto em tempo real;
✓Novos materiais com vistas à redução da massa específica (toneladas/MW);
✓ Novos sistemas de potência elétrica para redução de flutuações de carga e maior eficiência na conexão com o grid;
✓ Projeto de turbinas multi-megawatts, para diluir o custo de infra-estrutura, otimizar o uso do espaço e alcançar ventos de maior
altitude, os quais possuem maior velocidade e perenidade.

36. 36 / 58 Impactos e Riscos

37. 37 / 58
© Deepwater Wind Holdings, LLC
http://www.britannica.com/bps/media-view/154953/1/0/0
Desafios Culturais: ImpactoVisual
Simulação do impacto visual de um projeto embargado na costa de Massachussets

38. 38 / 58
Erikson, W.P., Johnson, G.D.
A summary and comparison of bird mortality
from antropogenic causes with an emphasis
on collisions.
Proceedings of the Third International
Partners in Flight Conference. March 2002.
Asilomar Conference Grounds, California.
Disponível em www.dialight.com/
FAQs/pdf/Bird%20Strike%20Study.pdf
Desholm, M.; Kahlert, J.
Avian collision risk at an offshore wind farm.
Biology Letters, 2005, vol. 1 no. 3 296-298
© 2005 The Royal Society
Desafios Culturais: Fauna Aérea

39. 39 / 58
Não se deve comparar apenas valores de investimento e de energia
Dalton, G.J. Lewis, T. “Metrics for measuring JOB CREATION by
renewable energy technologies, using Ireland as a case study.”
Renewable and Sustainable Energy Reviews, 2011, pp 2123–2133
▪ A energia eólica cria de 10 a 20 vezes mais
empregos por para uma dada capac. instalada a gás ou
carvão: enorme efeito multiplicador na capacitação da
educação e trabalho, no consumo local, e nos custos
evitados com assistência social e médica.
▪ Considerando inclusive a construção dos
equips. e usinas, as emissões de CO2 da
geração a carvão é 120 vezes maior que na
eólica, e a hidráulica (mat. org. inundado) é 6
vezes maior que na eólica, para a mesmo
volume de energia gerado. A eólica faz o
sistema público evitar um custo imenso com
as catástrofes naturais, doenças e perda de
força de trabalho (morte) provenientes da
poluição e mudança climática.
EXTERNALIDADES (custos ocluídos)
Desafios Culturais: Empregos e Externalidades

40. 40 / 58
40 / 35
Instalações anuais variam de acordo com a aprovação
anual pelo Congresso do subsídio Proction Tax Credit
Desafios Políticos (ex: Doações de Campanha nos EUA)
Ano da vitória deGW Bush,
originário da indústria de
hidrocarbonetos

41. 41 / 58
Proposta de um Supergrid Europeu
Potencial Escassez de Gás Natural na UE afetará
sobremaneira a logística do suprimento de energia

Desafios Estruturais (ex: UE)
Solução da Alemanha p/ o problema do “Spaguetti”:
Concessionárias de Distribuição ratearão o custo do
grid offshore principal, cobrando pelo transporte.



42. 42 / 58 Potencial Eof nos EUA (3.705TWh/ano*)
* No estudo de Musial e Butterfield, foi dado o
potencial para a potência e, assume-se aqui, um Fc
de 40% para calcular o potencial de energia.

43. 43 / 58 Potencial Eof na UE (3.028TWh/ano)
Consumo de Eletricidade
na Europa em 2009: 2.719 TWh
Fonte: Eurostat

44. 44 / 58 Ações do Parlamento Europeu

45. 45 / 58
Siegfriedsen; Lehnhofff; Prehn – Wind Engineering
Brasil: Grande Potencial Eof Mundial (publicações científicas)
Lu; McElroy; Kiviluoma – Proceedings of the Nat. Ac. of Sciences of the USA

46. 46 / 58
▪ Aumenta em mais de 50% o território brasileiro,
assim chamada não pela localização geográfica,
mas pelas gigantescas dimensões,
biodiversidade e recursos naturais.
▪ 2/3 da população mundial vive a menos de 50
km do mar, ou seja, 2% do território terrestre.
▪ No Brasil, 1/4 da população vive em municí-
pios litorâneos e 80% vive a menos de 200 km
do litoral, onde mais de 80% do PIB do
brasileiro é produzido.
▪ Tal espaço é portanto intensamente disputado e
deve ser estrategicamente preservado para
usos presentes e futuros os quais não se deem
em outros locais, e geração de energia elétrica
não é um destes usos.
▪ Poucos sabem que o pescado é a principal fonte
de proteína animal do mundo, com o triplo de
produção da carne bovina (150 Mton versus 50
Mton por ano).
▪ O Brasil é o 1º exportador de proteína bovina,
(1 Mton em 2011). Em 2009, a Noruega, país de
5 milhões de pessoas, exportou 7 Mton de
toneladas de proteína ictíaca (de peixe).
Amazônia Azul (I)

47. 47 / 58
▪ Não por acaso, a Noruega é o 2º exportador
mundial de gás e tecnologia offshore. Em 30
anos, saiu da situação de nação pescadora para o
1º IDH mundial ao promover planejamento,
tecnologia e exploração sinérgica de seus
recursos marítimos (alimento, energia e tecnol).
▪ A Noruega é assim um dos líderes mundiais no
desenvolvimento de tecnologia eólica offshore,
tendo meta de se tornar o maior exportador
mundial de energia eolielétrica offshore, para o
que já implementou a 1ª turbina eólica flutuante
de grande porte do mundo.
▪ A Petrobrás perfaz 10% do PIB do país, produz
85% de sua riqueza no mar, e estes números
aumentarão. A pesca mantém atualmente 800
mil empregos no Brasil, provendo a subsistência
já de 3 milhões de brasileiros. Mas ainda é uma
indústria pífia, pois o país exporta 37 mil ton,
importa 209 mil ton e o brasileiro consome
metade da média mundial de pescados, estando
1/3 abaixo do recomendado pela OMS.
▪ A fonte eólica offshore nutrirá a revolução que a
Amazônia Azul guarda para o Brasil, gerando esta
milhões de empregos relativos ao mar.
Amazônia Azul (II)

48. 48 / 58
155 km
1°  110 km
MA PI
CE
RN
PB
PE
SE
AL
BA
60 km
17 km
37 km
40 km
32 km
17 km
Batimetria: Nordeste
divisa estadual
capital
Para a batimetria inferior a 50 m, há
grande predominância de lâminas
d’água entre 9 e 13 m (tons laranjas)
Existem locais com lâminas d’água
inferiores a 5 m (tons marrons), com 17 a
37 km de extensão a partir da costa,
alguns bem próximos de capitais
(centros de carga)
Estuário do
Rio S. Francisco

49. 49 / 58
39° W 38° 30’ W
4° S
3° 30’ S
39° W 38° 30’ W
FORTALEZA
PORTO
PECÉM
EÓLICA
TAÍBA
FOR
Ventos e Batimetria no CE

50. 50 / 58
BA
ES
RJ
155 km
1°  110 km
Batimetria: BA, ES e RJ
divisa estadual
capital
Para a batimetria inferior a 50 m, há grande
predominância de lâminas d’água entre 9 e 13
m (tons laranjas)
Existem locais com lâminas d’água inferiores
a 5 m (tons marrons), com 17 a 37 km de
extensão a partir da costa, alguns bem
próximos de capitais (centros de carga)
100 km
160 km
95 km

51. 51 / 58 Ventos e Batimetria no ES
20° S
19° 30’ S
20° S
19° S
39° 30’ W
40° W
55 km
11 km 13 km 4 27 km
55 km totais

52. 52 / 58 Sinergia dentre o setor Eof e o de P&G (I)

53. 53 / 58 Sinergia dentre o setor Eof e o de P&G (II)

54. 54 / 58 Sinergia dentre o setor Eof e o de P&G (III)

55. 55 / 58 Sinergia dentre o setor Eof e o de P&G (IV)

56. 56 / 58
Investimento P&D e Instalação: € 53 M
Noruega – Junho de 2009
▪ A Noruega (4,8 M habs.) é 3º maior exportador mundial de gás natural e o 5º de petróleo (AIE).
▪ Apesar da economia altamente vinculada à energia fóssil (25% do PIB de US$ 247 bi em 2007),
somente a Noruega supera o Brasil no uso de hidroeletricidade (99,5%), pois possui 50% da
capacitade de reservatórios da Europa (fjords).
▪ Comissionamento da 1ª Turbina Flutuante de porte do mundo.
▪ Projeto da StatoilHydro com os fornecedores: Siemens, Technip, Nexans e Haugaland Power.

57. 57 / 58 WindFloat - Projeto Piloto já Comissionado
• Shareholders: Energias de Portugal, Repsol, Principle Power, A. Silva Matos (ASM), Vestas Wind Systems A/S and
InovCapital.
• 5km off the coast of Aguçadoura. This area had already two projects testing wave energy and had a substation,
and had a submarine network to connect the earth. EDP joined the substation EFACEC to buy this and use it in
this wind power project.
• First without heavy lift vessels or piling equipment. Projects can realise significant cost and risk reductions as a
result of the onshore fabrication and commissioning scheme.
• Over 60 other European suppliers, 40 of them Portuguese, supplied key components to the project.
• Construction of a bigger windfarm park now awaits EU funding.
• 20 million Euros.
• Vestas v80 2.0MW.
• 1,200 tonnes.
• Withstood waves of up to
15 m at the close of 2011.

58. 58 / 58 WinFlo – Projeto Piloto a ser Comissionado
The Winflo Project
• Coordinated by Nass&Wind Industrie, DCNS (ship building and marine renewable), and Vergnet (turbine engineering),
IFREMER (Sea Research Institute) and the University ENSTA-Bretagne.
• Life-size demonstrator to be tested in 2013.
• Machine to be manufactured in pre-series, and marketed from 2015
• Project’s budget is €35 million and received funding from “Investissements d’Avenir” (French state investment
programme on strategic topics).
• Pilot-farm is planned for 2016, before the first deployments due to take place from 2018 on.

59. 59 / 58 Alguns Conceitos paraTurbinas Flutuantes

60. 60 / 58
Obrigado pelo interesse !
JViterbo@Gmail.com
http://sites.google.com/site/JViterbo
http://www.teses.usp.br/teses/disponiveis/3/3135/tde-26092008-1045112o
Agradecimentos:
Dr. Domingos Urbano – Grupo de Estudos Ambientais / INPE
Eng. Odilon Camargo – Camargo Schubert Engenharia Eólica

61. 61 / 58
Major Phases of Project for an Offshore Wind Farm Construction

62. Offshore Wind Timescales
10
• Wind Turbines
• Offshore Cables
• Foundations
• Offshore Substation
• Onshore Substation
• Onshore Cables
• Environmental
Impact Assessment
and Main Consent
Application
2- 4
years
12 – 24 months
Construction
25 years
plus
O&M

63. Potential
Environmental Impacts
to be considered –
environment:
Designations
Conservation value
Marine mammals
Air Emissions
Benthos
Fish & Shellfish
Bathymetry
Archaeology
Coastal processes
Bats & Birds
Potential
Environmental Impacts
to be considered –
social:
Local Impact Assessment
Commercial & Sport Fisheries
Shipping and navigation
Archaeology
Leisure and Tourism
Visual impacts
Supply chain
Potential
Environmental Impacts
to be considered –
other infrastructure:
OWFs
Aggregates
Cables and Pipelines
Ports and Navigational Dredging
Disposal Sites
General Obstructions
Carbon Capture and Storage
Aquaculture
12
Offshore Works: Planning

64. ▪ Preliminary surveys, identification of
-Major obstacles
-Landowners
-Protected areas
-Need for horizontal directional drilling
▪ Geotechnical surveys of soil conditions
▪ Drawing of cable route, based on
-Geotechnics
-Access to cable site
-Construction logistics
-Minimal disruption to public life, transport etc.
-Minimal environmental impact
▪ Acquisition of permits
-Permanent permits for cable and substation sites
-Temporary permits for construction areas
•UK Evolution
- previous cable routes onshore 5-10km now
looking at 50km.
13
Onshore Works: Planning
BUILDING AN OFFSHORE WIND FARM

65. Submission
Hornsea Project One – 176 Documents
Hornsea Project Two – 181 Documents
Dogger Bank Creyke Beck – 182 Documents
East Anglia Three – 295 Documents
Hornsea Project Three – 183 Documents
14
All 1GW plus
Projects

66. Construction

67. 16
Construction Planning
– Geotechnical and Geophysical Surveys
– Rehearsal of Concept Drill
– Multimillion Euro contracts
– Strict deadlines
Flexibility
No
Unplanned
Delays
Consideration
of Linked
Activities

68. ▪ Pre-manufactured electrical equipment is
transported to substation site
▪ Construction of buildings
▪ Testing of HV equipment commences, incl.
safety tests
▪ Apart from substation sites, the land is
reinstated and returned to previous users
17
Onshore Substation Installation

69. Onshore/Intertidal Cable Installation in Europe
– Work area is fenced and wildlife is moved off site
– Top soil is removed and surface is prepared for
temporary structure
– Cable laying begins, combination of different
methods to minimise disruption
– Open trenches
– Horizontal directional drilling (eg under
roads/railways)
– Installation of ducts (tubes to contain future
cables)
– Cables are subsequently pulled through,
typically 1km at a time.
18

70. Offshore Substation Installation
– Often first component installed on site
– Jacket floated to site on barge
– Jacket lifted off barge and lowered to seabed
– Piles placed onto sea bed and then piles are driven into
seabed
– Pile/jacket connections are grouted
– Using a single lift, topside is lifted off barge and lowered
into position on top of jacket interface
19
Saipem Ltd
Saipem Ltd

71. Monopile and Transition Piece Installation
20

72. Offshore Array Cables
22
Transfers electricity from turbines to offshore substation
First pull-in:
– Cable is connected to pre-installed messenger wire at the OSS/turbine
foundation’s cable entry hole
– Pulled in from top of transition piece.
Surface laying:
– Cable is rolled out and laid on surface/in trench.
– If laid on surface, will be buried
Second pull-in:
– Cable is cut on ship and attached to foundation messenger wire
– To ensure cable is not bent beyond tolerance, a special quadrant
(semicircle-shaped cable holder) is lowered below sea level during pull-in
from foundation.
Quadrant going over board Diagram of second pull-in (Source: Siem
Offshore Contractors)
Offshore Export Cable
Transferring high-voltage electricity from the OSS to the transition joint bay
(TJB)
Offshore Substation pull-in:
– Use of quadrant and messenger wire as w/ array cables
Depending on cable length, cables may have to be jointed at sea
Crossings of pipelines and other subsea cables are often necessary
– Protection layer of rocks is laid on top of existing cable, and on top of
export cable once laid
Variety of Burial Methods:
Pre-trenching: separate operation to cut/dig trench
– Backfilled after operation or naturally backfilled by ocean currents
Simultaneous burial
– Use of special plough to cut groove and lay cable underground
– Cable is brought into groove from plough head
Post-lay burial
– Trencher (jetting or cutting) fluidize the soil on one or both sides of
cable and cable sinks into the seabed
– Progress rate depending on soil type and strength
– Cable Protection

73. Wind Turbine Installation
– Once foundation and transition piece
has been installed, wind turbine
components are loaded onto vessel.
– A modern installation vessel can
carry up to 8 turbines at a time.
– Vessel ‘jacks up’ and then using the
installation vessel’s crane, the turbine is
installed piece-wise:
– Turbine tower
– Nacelle (houses electrical
components and generator)
– Blades
– Installation follows the sequence of
cable and foundation installation to
get the turbines energised and
generating electricity as soon as
possible.
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74. Inspection Activities
– Foundations, eg
– Structure integrity
– Weld anomalies
– Steel corrosion
– Paint damage
– Occasional subsea inspection and inspection in confined space of
foundation
– Blades
– Use of high-quality camera equipment from turbine platform
– Use of drones
– Export and Array Cables
– Remote temperature monitoring along complete cable
– Subsea inspections
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Building an offshore wind farm

75. Bird Guano
– Controlling the levels of guano was critical from a health and safety
perspective to allow the site technicians to safely access turbines and
carry out inspections and repairs.
– Solution:
– Deep clean (rather than ad hoc), then deployment of full mitigations –
bird perches and snow fencing.
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