comparative cost-benefit analysis of load reduction
TRANSCRIPT
April 24th, 25th & 26th 2019 3
EVE JOHNSTON April 24th, 25th & 26th 2019 1
Eve Johnston
COMPARATIVE COST-BENEFIT ANALYSIS OF LOAD REDUCTION POLYMER COMPONENTS ON A EUROPEAN FOWT PROJECT.
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
The Case:
• Pre-commercial small farm
• Semi-submersible 6MW platform – catenary chain spread mooring system.
• Enigmatic environment in shallower water conditions, the ULS:
• >30m/s wind speed
• >10m significant wave height
The Challenge:
• High peak tension in ULS cases (design driver)
• Cost increase for small frequency conditions.
CASE STUDY – EUROPEAN FOWT PROJECT
April 24th, 25th & 26th 2019 2
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
Purpose of TFI Polymer Mooring component:
• Reduces compliance
• Reduce peak loads
• Minimise cyclic loading
How:
• Thermoplastic polymer compression shells • Material designed for cyclic loading
• Specifically designed non-linear stress-strain response
• Elongation of framework.
COST INNOVATION – POLYMER MOORING COMPONENTS
0
500
1000
1500
2000
0% 15% 30% 45% 60%
Load
(kN
)
Elongation (%)
Component Response
Response 1 Response 7
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
DESIGN PROCESS
110 120 130 140 150 160 170 180 190 200 210
End
Ten
sio
n (
kN)
Time (s)
ULS End mooring line tension
Chain Component 2
April 24th, 25th & 26th 2019 4
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
0
0,5
1
1,5
2
2,5
3
Mean (kN) Max (kN) Damage Life (years)
Comparitive Component Benefit
Original Chain Dia.
Chain case VS Component case
• Load reduction: • Greatest in extreme sea states.
• Benefits across most sea states.
• Minimisation of peak loads.
• Fatigue analysis: • Cyclic load reduction
• Frequency high load minimised.
• Damage reduction.
• Increase in fatigue life.
RESULTS- LOAD AND FATIGUE
Hs/Tp 5.2 7.8 9.1 11.7 13 15.6 18.2
2 5.6% 1.6% 4.1% 2.6% 2.0% 7.5% 8.7%
4 3.1% -1.8% 3.1% 2.2% -5.5% 8.0% 9.7%
6 -4.3% 2.0% 2.9% 20.0% 30.5% 40.0%
8 12.0% 37.5% 54.8% 61.7% 57.9%
10 71.5% 72.1% 67.5%
Percentage benefit on end loads
April 24th, 25th & 26th 2019 5
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
Direct Impact:
• Cost of Mooring Line: • Chain and anchor,
• Connectors and tensioners
• Cost of Platform • Connections, reinforcements
• Sizing
Secondary Impact:
• Cost of Mooring Installation • Decrease in bollard pull
• Decrease in vessel handling requirements
• Cost of Platform Installation
• Reduced Installation Risk
CAPEX
-60
-50
-40
-30
-20
-10
0
Z fr
om
MSL
(m
)
Horizontal Span (m)
Mooring Line 3 Touchdown
Min S1 - Max
S2 - Max C - Max
0,0
0,2
0,4
0,6
0,8
1,0
Line Anchor Connectors Total
Selected Mooring CAPEX (Comparison)
April 24th, 25th & 26th 2019 6
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
• Reduced Maintenance • Mooring: chain and anchor fatigue
• Platform: peak loads and fatigue
• Turbine: sudden impact damage
• Reduced Operations • Operational downtime
• Vessel size and time
• Port activities minimised
• Increased Capacity Factor • Due to decreased downtime
• Higher background load handling capability
OPEX AND AEP
0,0
0,2
0,4
0,6
0,8
1,0
Maintenace Port Activities Others Total
Selected OPEX (Comparison)
April 24th, 25th & 26th 2019 7
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
LCOE SUMMARY
European Floating
Offshore Wind Farm
+
Polymer Mooring Component
(First FOWT Deployment)
Peak Load and Fatigue Reduction
=
>12% saving in LCOE 0 0,2 0,4 0,6 0,8 1 1,2
CAPEX (€Million/MW)
OPEX (€Million/MWh)
AEP (MWh)
LCOE (€/MWh)
Comparative Cost Benefit
April 24th, 25th & 26th 2019 8
April 24th, 25th & 26th 2019 3
EVE JOHNSTON
PAUL MCEVOY
Questions ? Or want to get in contact:
COMPARATIVE COST-BENEFIT ANALYSIS OF LOAD REDUCTION POLYMER COMPONENTS ON A EUROPEAN FOWT PROJECT.
www.tfimarine.com
EVE JOHNSTON
April 24th, 25th & 26th 2019 9