Diese Präsentation wurde erfolgreich gemeldet.
Die SlideShare-Präsentation wird heruntergeladen. ×

Sustainable solutions for faster construction of the higher tower and foundation

Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Anzeige
Wird geladen in …3
×

Hier ansehen

1 von 23 Anzeige

Sustainable solutions for faster construction of the higher tower and foundation

Herunterladen, um offline zu lesen

Presentation by Martin Nilsson, Luleå Tekniska Universitet at Winterwind 2012, session 3b. "Sustainable solutions for faster construction of the higher tower and foundation"

Presentation by Martin Nilsson, Luleå Tekniska Universitet at Winterwind 2012, session 3b. "Sustainable solutions for faster construction of the higher tower and foundation"

Anzeige
Anzeige

Weitere Verwandte Inhalte

Ähnlich wie Sustainable solutions for faster construction of the higher tower and foundation (20)

Anzeige

Aktuellste (20)

Sustainable solutions for faster construction of the higher tower and foundation

  1. 1. Sustainable solutions for faster construction of the higher tower and foundation Tech. Dr. Martin Nilsson Luleå University of Technology Division of Structural and Construction Engineering – Structural Engineering Martin.C.Nilsson@ltu.se Prof., Tech. Dr. Milan Veljkovic Luleå University of Technology Division of Engineering and Construction Structural – Steel Structures Milan.Veljkovic@ltu.se
  2. 2. Agenda •  Introduction, demands on improved competitiveness. •  The complete assessment: design, environmental and economical life cycle assessment. •  Innovations in foundations. •  Conclusions.
  3. 3. Future requirements By year 2020, 30 TWh of the electricity consumption in Sweden should be produced by wind power. (Target by Swedish Wind Energy). Wind power plants will be constructed at remote locations, in short time and under harsh climate conditions. The plants must have good locations, good turbines and be built both quickly and competitively Wind power plants must be designed with sustainable solutions, both environmentally and economically. Turbines have to be built higher than 100 m to gain stable and more constant wind.
  4. 4. New demands for competitiveness on wind energy sector The future requirements impose new demands on costs and effectiveness of: –  turbine design, –  wings, including de-icing where necessary, –  bearing structural components – towers and foundations, production and assembling for higher towers
  5. 5. Economics of Wind Power UK experience On‑shore Offshore Element Cost as % of total Cost as % of total • Turbine • 33% • 21% • Blades • 22% • 15% • Tower • 20% • 13% • Foundation • 9% • 21% • Grid connection • 6% • 21% • Design & Management • 10% • 9% • Total cost per MW • €1.5 - 2 million • €2.5 – 3.5 million
  6. 6. Existing and alternative tubular steel tower solutions
  7. 7. Existing concrete tower solutions Prefabricated elements In-situ cast with slip form 1 2 3
  8. 8. Environmental and economical assessment Economical and environmental life cycle assessment of an on-shore wind power structure focusing on embodied equivalent CO2 emissions and energy consumed in manufacturing, transportation, erection and dismantling. Example from Master Thesis by Josep Pigem Rodeja, LTU: The mass of CO2 and energy used per produced kWh at consumers place for a 100 m high tubular steel tower and a pre-stressed concrete tower with foundation
  9. 9. Environmental and economical assessment Approximate structural design, equivalent loading P 1.  Ultimate Limit State (ULS) - Enough strength of materials. - Instability phenomena. P 2.  Fatigue Limit State (FLS) - Steel: structural details. - Concrete: Separately by material O 3.  Dynamic Stability - Vibration behaviour. - Avoid resonance problems.
  10. 10. Environmental and economical assessment Ømin = 3m Geometrical approach 100 m Cross-section Conical tower
  11. 11. Environmental and economical assessment Steel tower Concrete tower Østrand = 15.7 mm ns = 12 ntendon = 56
  12. 12. Environmental and economical assessment Material data Carbon intensity Energy intensity Material Recovery [kg CO2/kg] [MJ/kg] Steel plates 11.78 0.800 11 % reused, 88 % recycled, 1 % landfill Reinforcement 12.42 0.870 11 % reused, 88 % recycled, 1 % landfill Concrete 0.50 0.091 5.8 % recycled, 94.2 % landfill Reinforced concrete 0.53 0.099 5.8 % recycled, 94.2 % landfill EPD – Environmental Product Declarations, www.environdec.com
  13. 13. Environmental and economical assessment Manufacturing Pre-stressed concrete tower Carbon Energy Tubular steel tower Material intensity intensity Carbon Energy [tonne] [GJ] Material intensity intensity Concrete [tonne] [GJ] 172.1 921 segments Steel plates 232.6 3 426 Steel tendons 63.1 901 Concrete 169.9 934 Reinforcement 22.9 326 Reinforcement 36.9 526 Concrete 95.5 525 Sum 439.4 4 866 Sum 353.6 2673 Carbon intensity [Tonnes CO 2] 500 6000 Energy intensity [GJ] 400 5000 232,6 4000 300 3000 3426 235,2 200 2000 1822 100 206,8 1000 118,4 1460 851 0 0 Steel tower Concrete tower Steel tower Concrete tower
  14. 14. Environmental and economical assessment Transportation Pre-stressed concrete tower Carbon Energy Tubular steel tower Material intensity intensity Carbon Energy [tonne] [GJ] Material intensity intensity Concrete [tonne] [GJ] 13.49 195.5 segments Steel plates 3.41 49.5 Steel tendons 0.14 2.1 Concrete 1.28 18.5 Reinforcement 0.05 0.7 Reinforcement 0.08 1.2 Concrete 0.72 10.4 Sum 4.77 69.2 Sum 14.4 208.7 Carbon intensity [Tonnes CO 2] 16 250 14 Energy intensity [GJ] 200 12 10 150 8 13,63 100 197,5 6 4 3,41 50 49,5 2 1,36 0,77 19,7 11,2 0 0 Steel tower Concrete tower Steel tower Concrete tower
  15. 15. Environmental and economical assessment Erection (fuel consumption of cranes, foundation excluded) Tubular steel tower Pre-stressed concrete tower Carbon Energy Carbon Energy Material intensity intensity Material intensity intensity [tonne] [GJ] [tonne] [GJ] Steel plates 8.46 94.8 Concrete segments 13.49 834.0 Sum 8.46 94.8 Sum 13.49 834.0 Carbon intensity [Tonnes CO 2] 80 900 000 70 Energy intensity [GJ] 800 000 60 700 000 600 000 50 500 000 40 74,42 831 041 400 000 30 300 000 20 200 000 10 100 000 8,46 94 808 0 0 Steel tower Concrete tower Steel tower Concrete tower
  16. 16. Environmental and economical assessment Dismantling (recycling/incinerating plant situated 200 km away) Tubular steel tower Pre-stressed concrete tower Carbon Energy Carbon Energy Material intensity intensity Material intensity intensity [tonne] [GJ] [tonne] [GJ] Steel plates 28.70 416.0 Concrete segments 37.60 546.0 Sum 28.70 416.0 Sum 37.60 546.0 Carbon intensity [Tonnes CO 2] 40 600 35 Energy intensity [GJ] 500 30 400 25 20 37,60 300 546,0 15 28,70 416,0 200 10 100 5 0 0 Steel tower Concrete tower Steel tower Concrete tower
  17. 17. Environmental and economical assessment Total carbon and energy intensity Tubular steel tower Pre-stressed concrete tower Carbon Energy Carbon Energy Material intensity intensity Material intensity intensity [tonne] [GJ] [tonne] [GJ] Manufacturing 439.4 4886 Manufacturing 353.6 2674 Transportation 4.8 69 Transportation 14.4 209 Erection 8.5 95 Erection 74.4 834 Dismantling 28.7 416 Dismantling 37.6 546 Sum 481.4 5466 Sum 480.0 4262 Carbon intensity [Tonnes CO 2] 500 6000 28,7 8,5 37,6 Energy intensity [GJ] 416 400 74,4 5000 95 4000 546 300 834 3000 439,4 4886 200 353,6 2000 2674 100 1000 0 4,8 14,4 0 69 209 Steel tower Concrete tower Steel tower Concrete tower
  18. 18. Environmental and economical assessment Embodied CO2 in electricity produced Total emissions Electricity produced g CO2/kWh [tonnes] [GWh] Steel tower 480.1 70.1 6.85 Concrete tower 481.4 70.1 6.87 Energy payback time Embodied energy Produced Energy Months to recovery [MWh] [MWh] Steel tower 1 518.3 292 5.2 Concrete tower 1 183.9 292 4.1
  19. 19. Innovations in foundations More prefabrication E.g. more prefabricated reinforcement: - cages - cell reinforcement - roll out reinforcement
  20. 20. Alternative reinforcement solutions in foundations Cell reinforcement – a new type of reinforcement in high strength steel (1000 MPa). Rows of rings with specific ring diameters with great ductile capability. Several rows of rings in two different directions form a net reinforcement. Vindforsk project on-going with dynamic tests of cell-reinforced beams and slabs for possible application in foundations.
  21. 21. Alternative reinforcement solutions in foundations Cell reinforcement Example from static tests: Yield strength 500 MPa Ductile behaviour     10∅8-­‐ N   s120   3∅12   6   LYING   ROWS   325   450   325   325   450   325   Reference   beam,   Ø12 Cellreinforced   beam,   6   lying   rows   Docol   500 L1       L1       450 450 L2       L2       400 400 L3       L3       350 350 300 300 Load   [kN] Load   [kN] 250 250 200 200 150 150 100 100 50 50 0 0 0 5 10 15 20 25 30 35 40 45 50 55 60 0 5 10 15 20 25 30 35 40 45 50 55 60 Deformation   [mm] Deformation   [mm]
  22. 22. Conclusions •  The competiveness of a wind power plant relies on 1. good wind conditions, 2. good and reliable turbines, 3. the height of the towers and how fast and cheap they can be built •  Requirements for building higher towers: more cost effective, lower (no) maintenance costs, competitive foundations. •  Solution is in innovations in the construction sector, that has a supportive role for the wind sector but may improve the image. Innovations such as new assembling techniques for steel towers, new reinforcement, design and construction of foundations, blade materials and design …
  23. 23. Conclusions •  Environmental and economical assessment are important tools for future investments (given example shows almost no difference between steel or concrete structures; about 7 g CO2/kwh) •  Possible solutions and competence are within Swedish Universities of the Built Environment (LTU, Chalmers, KTH, LTH) where further improvements are planned.

×