Danish Society for Naval Architecture and Marine Engineering, Danish Maritime Society, The Transport Innovation Network & Danish Wind Energy Group

Transcription

1 O&M of Offshore Wind Turbines Experiences and Future Challenges 1-day Conference, 30 April 2012 in Copenhagen Niels Agner Jensen Sr. Project Manager, Team Lead, DONG Energy Wind Power, Maritime & Vessel Management Danish Society for Naval Architecture and Marine Engineering, Danish Maritime Society, The Transport Innovation Network & Danish Wind Energy Group DONG Energy Wind Power Experiences from Existing Sites Future Challenges What's in the Crystal Ball? 2 1

2 DONG Energy is one of the leading energy groups in Northern Europe. We are headquartered in Denmark Our business is based on procuring, producing, distributing and trading in energy and related products in Northern Europe. We have approximately 6,000 employees and generated DKK 57 billion (EUR 7.6 billion) in revenue in EXPLORATION & PRODUCTION WIND POWER THERMAL POWER ENERGY MARKETS SALES & DISTRIBUTION DONG Energy Wind Power Wind Power develops, constructs and operates wind farms in Northern Europe. The focus is on the UK and Germany as the largest growth markets. REVENUE DKK 4.3 BN 6% EBITDA DKK 1.8 BN 13% EMPLOYEES (FTE) % The percentages indicate the proportion of the Group that each business area accounted for in

3 Market shares Offshore wind in operation Denmark 45% UK 21% Electricity generation Denmark 54% Heat generation Denmark... 35% Electricty sales Denmark... 20% Netherlands... 1% Gas sales Denmark... 29% Sweden... 22% Netherlands... 1% Electricity distribution Denmark... Gas distribution Denmark... 28% 29% Existing and planned wind capacity - MW For , wind farms for which a final investment decision has been made are shown. MW denotes DONG Energy s proportionate ownership interest. 3

4 DONG Energy has a significant portfolio and a strong pipeline of future offshore and onshore wind projects IN OPERATION UNDER CONSTRUCTION UNDER DEVELOPMENT Walney 2.5 Walney 1 +2 WoDS Barrow Burbo Lincs Gunfleet Sands 1+ 2 Burbo 2.5 London Array 2 Westermost Rough London Array Mehuken 1 Mehuken 2 Storrun Other Danish onand offshore Anholt Horns Rev 1+2 Nysted Borkum Karcino Riffgrund 1 Borkum Karnice Riffgrund 2 Lake Ostrowo Borkum Riffgrund West Our offshore wind projects are centred around key North western Europe UK Germany Denmark Poland is the key onshore growth market Ploudalmezeau NOTE: Walney II had first power in November 2011, but is not yet fully commissioned. 7 DONG Energy Renewables Experiences from Existing Sites Future Challenges What's in the Crystal Ball? 8 4

5 O&M on existing sites are based on Crew Transfer Vessels On DONG Energy's sites purpose-built or chartered CTVs are used, while one partner site uses CTVs in combination with helicopters 9 Key Parameters for O&M Logistics? 5

6 General Experiences with different hull forms Monohull Pros: Comfortable ride to/from the wind farm Cons: Problematic roll when manoeuvring at low speed, narrow fore deck, small deck area Catamaran Trimaran Pros: Small hull resistance, large deck, many yards Cons: High GM => large roll accelerations, risk of slamming under wet deck) Pros: "The best" from monohull and catamaran Cons: Few yards, expensive to build, difficult to find the optimum hull form, difficult engine arr. SWATH Pros: Comfortable ride, high performance Cons: Expensive to build, difficult engine access DONG Energy Renewables Experiences from Existing Sites Future Challenges What's in the Crystal Ball? 12 6

7 Future Challenge: Borkum Riffgrund Borkum Riffgrund I Offshore Wind Farm (BKR01) is situated approx. 40km north of the island Borkum 12 WTGs from Borkum Riffgrund II Offshore Wind Farm (BKR02) are placed to the northeast of BKR01 Distance between centers of BKR01 + BKR02 and BKR West is ~21km The three parks encompass up to 240 WTGs and 0.9 GW capacity, but will become operational at different points of time Key data for parks in the Borkum cluster BKR01 BKR02* BKR West* Total Number of WTGs ** '* Siemens Siemens Type of WTGs???? SWT SWT Capacity 320 MW 302 MW 240 MW 862 MW Distance to harbour (Norden) Distance to airfield (Norden) Weather downtime ~65 km ~65 km ~56 km ~56 km ~45%*** ~45%*** ~85 km ~78 km ~45%*** Current ownership DONG + partners DONG DONG Average taking over date Nov 2014 Jul 2015 Jun 2017 * Final Investment Decision not made yet ** Depends on turbine type *** Depends on setup 14 7

8 The Borkum cluster is located far from shore, which reduces net hours to around 6 hours with a traditional crew boat set-up Technician working day when travelling from harbour in Norden-Norddeich to BKR01&02 Hours per activity, based on crew boats travelling with a speed of 17 knots Working day Preparation Travel time WTG transfer Lunch break Acclimatisation Effective working time Consequences of long boat travel 15 An offshore accommodation may increase net hours substantially, and costs can be motivated as scale increases Having an offshore accommodation increases effective working hours, saving scheduled workdays Total travel time savings increase by park size, why a larger park can motivate an OAU investment Effective hours per 12h workday at BKR01& h Otherwise lost due to travel time and acclimatisation Annual savings BKR West BKR02 From shore From OAU BKR01 Scheduled savings per WTG and year XX saved workdays per WTG and year Technicians cost YY per workday ZZ per WTG/year, equal to a ~10% cost reduction Number of turbines 16 8

9 Decisions on offshore accommodation generally depend on a number of key dimensions: Rationale for dimensions i Number of WTGs CTV or CTV & helicopter Should an offshore accommodation unit be used? No Yes Distance to harbour/airfield Offshore accommodation Effect on effective working hours from having OAU increases with distance, regardless of what type of OAU is used A higher number of WTGs lowers CAPEX/OPEX per MW for the OAU * Average distance to WTG from centre of cluster a longer distance is implied by a higher number of WTGs ** Depending on cluster size *** MCGOAU = Motion Compensated Gangway Offshore Accommodation Unit or simpler: "Ampelmann" vessel 17 ii Number of WTGs / cluster size* What type of offshore accommodation unit is optimal? Floatel or "Ampelmann" vessel** Floatel Bad weather days "Ampelmann" vessel The MCGOAU*** advantage increases as weather conditions get worse and park size increases Since the different OAU concepts are positioned differently in / outside parks, transport time is affected by park/cluster size Illustrative & conceptual Four offshore accommodation solutions are being evaluated: platform, floatel, Ampelmann ship, and jack-up Platform Floatel* "Ampelmann" ship Jack-up Description Construction of a permanent platform on site Stand-alone, connected to substation or integrated with substation Accommodation barge that is moored near the park Can be equipped with helipad, davit cranes, etc. Accommodation ship that can travel within the park due to DP2 system Can be equipped with an Ampelmann gangway system Jack-up with integrated accommodation Self-propelled or towed Can be equipped with repair crane + High degree of comfort Can be shared with nearby parks Proven concept at Horns Rev II Relatively low leasing cost Stable in high waves Flexible accommodation capacity Can be shared with other wind parks or construction sites Can provide WTG transfer in high waves without relying on helicopter support Can be shared with other wind parks or construction sites High degree of comfort Can save cost for rented jackup during campaign period Can be shared with other wind parks or construction sites Immobile and therefore limitations on which parks it can support Requires large investment Mooring points have to be established for each location Requires tugboat for relocation Discomfort due to floating solution Most likely requires a large investment or long-term lease Less flexible than a ship Most likely requires a large investment or long-term lease Source: DONG interviews; Svitzer UK & Sanderson Maritime / SC Chambers, SeaEnergy; Jack-Up Barge; A2SEA 18 9

10 For all of the above a "daughter craft" and a Launch & Recovery system is relevant Courtesy of Hvide Sande Ship & Boatbuilding Company 19 The considerations for BKR are not finalised. but here are some of my personal favourites: Courtesy of SVITSER and Knud E. Hansen A/S Courtesy of DAMEN and Workships Contractors BV 20 10

11 DONG Energy Renewables Experiences from Existing Sites Present & Future Challenges What's in the Crystal Ball? 21 The Carbon Trust OWA TWG on Vessels and Access had many competition entries which might be used in the future wind farms far from shore. 11

12 Carbon Trust OWA Access Competition results: Carbon Trust cont. 12

13 Carbon Trust cont. 13

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15 Questions? Horns Reef 2 Offshore Wind Farm 15