Download - Jaime de Rábago · PRECAST CONCRETE WIND TOWERS AND OFFSHORE FOUNDATIONS: A HUGE MARKET COMING AHEAD
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PRECAST
CONCRETE
WIND TOWERS
AND
OFFSHORE
FOUNDATIONS:
A HUGE MARKET
COMING AHEAD
Jaime de Rábago,
Managing Director, Consolis Hormifuste S.A.
Madrid, 13/05/2011
EOI: Claves para emprender en renovables
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Content
About Consolis Group
About Consolis Hormifuste
Understanding wind
Consolis Hormifuste products and services
Consolis Hormifuste onshore
Consolis Hormifuste offshore
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Consolis history
100+ years of history
Consolis Oy in Northern Europe
Bonna Sabla in France & North Africa
Today, European leader
in pre-cast concrete industry
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Activity area (23 countries):
• Europe
• North Africa
• Asia
Personnel: ~ 10000
Turnover: + 1500 M€
Factories: ~ 130
Headquarter: Brussels
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Solutions for
•Residential & non-residential
buildings
•Railways
•Civil works (pipes,
environment etc.)
•Unlimited…
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Continuous innovation
Consolis Technology (Finland-France) at
the cutting edge
Developing pre-cast concrete concepts,
products, manufacturing processes and raw
materials to improve productivity and quality
Technology Roadmap
boosting internal co-operation
Consolis Innovation Training (CIT)
• intensify & better manage innovation
• improve the transfer of best practices
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People & practices
Skills development – a top priority
Training – a major investment
Consolis Academy
Transfer of best practices (TOB)
sharing experience among Consolis companies
International functional networks
sharing knowledge and building synergies
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Respect for the environment
New ideas for sustainability over the entire product life cycle
better use of materials
production with reduced environmental burden
design for re-use/dismantling/recycling
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The wind tower centre of Consolis, located in Madrid
Since 2008 a member of Consolis Group and since 2005 in the renewable energy business.
Coordination of product development and design
Certification of solutions
Customer relationships
Coordination of marketing and sales
Consolis Hormifuste S.A.
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Understanding wind
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How we obtain the energy from wind?
FORMULA: and
So, energy is:
in square proportion to rotor diameter
in cubic proportion to wind speed
Wind energy basics
A: Area of the rotor
D: Rotor diameter
V: Wind speed
P: Power output
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hub height
rotor diameter
... both parameters of
paramount
IMPORTANCE
to increase
energy production
Wind energy basics
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90
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The world wind industry
Today: nearly 200.000 Mw
installed in a global scale
-Year 2015: 500.000 Mw
-Year 2020: ….nearly
1.100.000 Mw!!
-Wind industry: growth,
growth, growth
One tower (windmill) = 2 - 5 MW
On-shore / off-shore0
100,000
200,000
300,000
400,000
500,000
600,000
700,000
800,000
900,000
1,000,000
1,100,000
1990 2010 2015 2020
MW
Cumulative Global Wind Power Development
Prediction Forecast Existing capacitySource: BTM Consult - A Part of Navigant Consulting -March 2011
Actual 1990-2010 Forecast 2011-2015 Prediction 2016-2020
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The evolution of MW
per WTG in different
segments is as follows
(average composed
nominal power)
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
> 2,5 MW 1,5-2,5 MW 0,75-1,49 MW < 0,75 MW
Source: real data up to 2009, then, own estimations
From MW to concrete towers
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A market of bigger and higher machines…
1970 1980 1983 1985 1987 1990 1995 1998 2000 2003
10 15 20 25 30 50 60 70 85 110
5 11 12,5 20 23 48 58 61 77 116
5 20 30 100 100 600 1100 1200 1500 5000
Year
Height (m)
Rotor Ø (m)
Power (kW)
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Why concrete towers for the wind industry?
… there are technical reasons…
Less maintenance requirements
More flexibility of construction and design
Better dynamic response (less vibrations and fatigue)
Better transportation possibilities
Precast plants can be easily adapted for manufacturing of
concrete towers
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… and economic reasons
Variation of steel prices
With greater and higher wind
turbines (> 100 meters), the
concrete solutions for towers is
cheaper
The tower can account for up to
20-25% of the total wind farm cost
and this percentage increases
with greater turbines
Why concrete towers for the wind industry?
60 70 80 90 100 110 120 130 140 150
Approx. cost comparison
between concrete and steel
wind towers
Concrete
Steel
Tower height (metres)
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Consolis product range for wind farms
Onshore
• Hybrid precast concrete-steel towers
• Full precast concrete tower
Offshore
• Precast concrete gravity based foundations
Consolis does
Design
Production
Transportation to the building site
Assembly and other site works
Post tensioning
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Hybrid precast
concrete-steel tower
- max height 150 m
Post tensioning
cables
Steel part
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Full concrete tower
- max height 105 m
Intermediate slab
Post tensioning
cables
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Consolis
Hormifuste
solution
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1. Technical Introduction
1.1 Basic Vocabulary
1.2 Classical Structures vs. Wind Towers
2. General Calculation Scheme
3. Calculation Process
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3
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Wind Turbine Manufacturer Data
Geometry and Post-tension
Pieces reinforcement
Joints
Consolis Hormifuste solution
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1. Technical introduction
1.1. Basic Vocabulary
• Geometry: tower shape
• Joints: connections between pieces
•Own frequency of structure: dynamic behaviour parameter to be
controlled in order to avoid interaction with the turbine→ Resonance
• ULS: Ultimate Limit State of strength, stability and fatigue. Loads that
should cause the collapse of the structure
• SLS: Serviceavility Limit State. We differentiate between extreme loads
(50 years return period) and frequent loads (one year return period)
• Fatigue: Time repeated loads → load cycles and damage accumulation
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1. Technical introduction
1.2 Classical Structures vs. Wind Towers
In an classical structure ,design is
conditioned by SLS and ULS. Once we
have the structural design the fatigue is
checked.
In concrete wind towers initial design is
conditioned by SLS and fatigue. After this,
ULS are checked. Fatigue is determinant in
calculation, as the cycles are huge (108)
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2. General Calculation Scheme
WT Manufacturer Data
Max. Fatigue Load
Geometry and
Post tension
Own
Frequency
SLS
Pieces
reinforcement
Geometry
Modification
General
Joints
Vertical
Horizontal
Fatigue
Loads
Accumulated damage
ULS, shear and torsion
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3
4
2
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3. Calculation process
Wind Turbine Manufacturer Data
Main data to be provided by Wind Turbine Manufacturer:
Loads and Markov Matrix of bending moments at different heights of the
tower
Clearance: Minimum distance to maintain between blade tip and the
tower.
Frequency: Tower Frequency used in loads calculation.
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3. Calculation process
Ring Number
of
elements
per ring
Weight of
each
element
1 6 25,4
2 6 26,9
3 6 26,4
4 5 28,2
5 5 24,7
6 4 24,5
7 4 22,8
8 3 28,3
9 3 26,1
Detailed geometry
Once the geometry and
post tension is
confirmed, the tower is
divided in precast units
(rings and elements per
ring)
Geometry and Post-tension2
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Reinforcement of precast elements
3. Calculation process
Horizontal reinforcement is
necessary to support shear and
torsion forces caused by temperature
gradient between inner and outer
part of the tower
Vertical reinforcement is only
necessary for handling of pieces
Pieces reinforcement3
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Joints4
3. Calculation process
Detail of the horizontal jointDetail of the vertical joint
Proper
reinforcement
and grouting of
vertical joints
during assembly
will assure the
monolithic
behaviour of rings
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Our first project:
100 metres hybrid towers in Finland
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Consolis Hormifuste solutions for offshore
Since 2007, Consolis-Hormifuste has carried out several works concerning offshore
wind turbines. These works range from basic studies to the designs of a concrete
foundation structure, designed to perform in different conditions.
The following studies have been developed until now:
•Research proposal for offshore concrete foundations for wind turbines
• Structural and stability calculations for an offshore windturbine foundation
• Foundations for offshore wind turbines: state of the art
• Founfations for offshore wind turbines: Analysis of structural solutions
• Foundations for offshore wind turbines: Analysis of a conical caisson in locations with
25 m of depth
• Foundations for offshore wind turbines: Analysis of precast pieces for a foundation
structure in locations with 25 m of depth
In the following slides, a summary of these works is made.
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Consolis Hormifuste solutions for offshore
RESEARCH PROPOSALS
In this study, a brief and preliminar state of the art was made, and some researchlines were proposed:
• Predesign abacus
• Construction methodologies
• Economic evaluations
• Environment evaluations
Some of these lines would be developed then in the following works
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Consolis Hormifuste solutions for offshore
STRUCTURAL AND STABILITY CALCULATIONS FOR
AN OFFSHORE WIND TURBINE FOUNDATION
Here, a design of a foundation made of a reinforced concrete caisson was developped.
The caisson was designed for depths from 10 to 30 meters, and with the ability to betransported afloat .
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Consolis Hormifuste solutions for offshore
ANALYSIS OF STRUCTURAL SOLUTIONS
Two structural solutions were studied here, both of them valids to perform at depths of
50 m.
Both solutions were designed to be transported afloat.
Solution #1: a
conical caisson
supporting a
cylindrical structure
Solution #2: three
piles supporting a
cylindrical structure
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Consolis Hormifuste solutions for offshore
CONICAL CAISSON IN LOCATIONS FOR UP TO 25m SEA DEPTH
(2009-2010)
It was inferred from the former study that the conical solution had lower costs than thethree pile solution.
A foundation structure for 25 m depth, made of a conical caisson which was able tobe transported afloat was designed.
The following calculations were carried
out for this solution:
•Buoyancy of the foundation structure
•Geotechnical stability
• Structural calculations
• Estimated costs
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Consolis Hormifuste solutions for offshore
ANALYSIS OF PRECAST PIECES FOR A FOUNDATION STRUCTURE
IN LOCATIONS FOR UP TO 25m SEA DEPTH
Finally, a design of the conical caisson making
use of precast pieces was developed.
-The foundation structure was made to perform
up to 25 m depth.
-It was designed to be built on the coastline
and then transported afloat.
-The reinforcement was made with
post-tensioning tendons, due to the high tensions.
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Offshore foundation for
up to 25m sea depth
Bottom diameter: 22 m
Height of conical part 18,5 m
Total height 25 m
The foundation has vertical
and horizontal post tension.
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Offshore costs... the big battle in the
coming years
Cost comparison? Not yet possible in real terms:
A lot of different sites, depths and tipologies
Good reference: Vattenfall Kriegers Flak conceptual
foundation study (5Mw, 35 metres, 40 foundations, 5 types:
between 2,4 Meur to 3,8Meur)
Our solution has a clear aim: reducing cost in the production
phase. Transportation and installation should not vary a lot
from other solutions.
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Precast advantages for offshore...
Serial production as big amount of pieces to be
precasted
High quality guaranteed at factory
Pieces easy to transport (no more than 20 tons each)
to harbour or to coastline
Small area needed in harbour and or coastline
Possibility of keep independent production from
installation: not dependent on weather conditions…
Sea tranportation not too difficult…
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We want to avoid this...!
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.. and even this...!
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CONSOLIS HORMIFUSTE S.A.
C/ José Silva, 3 4ºD
28043 Madrid (SPAIN)
www.consolis.com
Let’s harness wind together!!