HKZ offshore grid Rob van der Hage
Stay tuned. Safety first! For your safety as well as our own we would like to draw your attention to the following safety measures. In case of an emergency, the following instructions also apply: Follow the escape route as indicated. Use the stairs instead of the lift. o the assembly point. Follow the instructions of the in-company emergency worker who is present at that moment.
Programme 09h00 Room open 09h45 Welcome 10h00 Technical topics - Overview grid connection system & requirements - Overplanting - Platform design 11h00 Coffee break 11h15 Legal topics - Overview legal framework - Highlights developments 12h00 Closing & Lunch 13h00 End of session
Offshore wind NL Staged development until 2050: Stage 1: 2019 2023 Stage 2: 2024 2035 Stage 3: 2035 2050 3,5 W in 2023 (NL: Energie akkoord) 1 W/year (NL: Energie agenda) 180 W (Paris agreement; total EU, Northsea region)
Hollandse Kust (zuid) 2 x 700MW Hollandse Kust (zuid) Alpha and Beta Rijkscoördinatieregeling (RCR) applicable October 2016: Preferred route determined: onshore landing in Maasvlakte-Noord February : Permit applications submitted End of September: publication of draft permits, spatial plan and EIA expected Offshore surveys: soil investigation ready, detailed UXO survey planned for 2018 Tender of contractors for platform and cable started
Offshore grid scheme Hollandse Kust (zuid)
TenneT s offshore grid connection system Five platforms, capacity 700 MW Export cable system: 220 kv, AC Standardisation 66 kv cables Lean and mean (bundling) Developed with market parties Minimal habitat disturbance
Technical Single Line Diagram (SLD) Change grid code: U-Q diagram Harmonics Overplanting Curtailment Lay-out platform (3D model)
Technical BSL380 BSA2 ATA10 400 MVA 380/220/33 kv uk = +/- 14% ATA20 400 MVA 380/220/33 kv uk = +/- 14 % AT10 80-140 MVAr AT11 65 MVAr AT12 32.5 MVAr AT20 80-140 MVAr AT21 65 MVAr AT22 32.5 MVAr BSA1 AT10 70 MVAr AT20 70 MVAr ATA10 400 MVA 230/66/66 kv uk = +/- 12% ATA20 400 MVA 230/66/66 kv Uk = +/- 12%
Voltage Level Platform 66 kv [pu] Technical Change in grid code U-Q diagram 1,15 1,1 1,05 1 0,95 0,9 0,85-0,5-0,4-0,3-0,2-0,1 0 0,1 0,2 0,3 0,4 0,5 Reactive Power Platform [pu]
Technical U-Q diagram
Technical Harmonics Per section (not per string) OWF responsibility: to calculate their (planning) levels alignment on data exchange between OWF and TenneT Compliancy comparison measurement with approved planning levels Harmonic filters (if any) can be connected to 20 kv winding (i.e. active filters)
Overplanting Content Calculation methodology Overview of areas which could be leading for cable design Case dynamic ampacity: Landstation area Final remarks / disclaimer
Overplanting Calculation methodology Raw survey results Layers of soil with soil properties determined Actual in-situ and lab tests on thermal resistivity Based on raw results: determination of effective -value @ DOB Cable design will be based on continuous ampacity for 350 MW Dynamic ampacity for 380 MW: the time available for (over)loading the cable with a current equivalent to 380 MW. In this presentation this time is derived based on conductor temperature of 90 C with preloading conditions of 67% of 380 MW. PLEASE NOTE: Onshore 380 kv cable connection not included (detailed analysis ongoing) 14
Overplanting Areas with worst case installation conditions for ampacity: Landstation Horizontal Directional Drillings (HDD s) Sanddump area Offshore part (sandwaves) Offshore part Sand dump area HDD's (orange) Landstation 15
Overplanting Analysis of areas (1/2) Effective thermal resistivity values (K*m/W) with expected soil coverage for all route sections will be included in paper (new version specifically for HKZ offshore grid) Landstation HDD s Possibly cable design optimised at 350 MW static with 1,2 m soil coverage: worst case -> See case example Clay layer at ~25-30 m depth: effective -value: max 0,7 K*m/W Deepest point at 55 m: effective -value: 0,4 K*m/W Very deep installation conditions: not relevant for 380 MW dynamic case (in relation to 350 MW static case) 16
Overplanting Analysis of areas (2/2) Sanddump area Significant layers of clay present Sandwave area Significant sand waves present on export cable route Sandwaves based on nonmobile reference level (NMRL) Area Thermal resistivity (K*m/W) Sand dump 0,83 5,5 Sand dump 0,65 14,5 Offshore 0,55 7,0 Offshore 0,6 3,5 Example on determination of NMRL Soil coverage (m) 17
Overplanting CASE: Landstation (1/2) Lower DOB (soil coverage) means less dynamic ampacity in relation to the 350 MW static design requirement. Therfore Landstation is considered worst-case scenario for 380 MW dynamic ampacity with only 1,2 m soil coverage Ampacity calculation assumptions for this case: Due to possible soil dehydration, usage of backfill Thermal resistivity just low enough to reach 350 MW static ampacity (= 940 A for Alpha, one sided reactive power compensation) Two possible cable types assessed: 1600 mm 2 AL with galvanized steel armour (S) λ 1 + λ 2 = 0,65 = 0,8 K*m / W 1600 mm 2 AL with stainless steel armour (STS) λ 1 = 0,28 ; λ 2 = 0 = 1,0 K*m / W 18
Overplanting CASE: Landstation (2/2) Results of dynamic ampacity simulation 380 MW: Available time is estimated at ~200 hours 19
Overplanting Final remarks The dynamic rating for 380 MW as stated in this presentation is a preliminary value based on assumptions as explained. Amongst others following may finally alter the presented dynamic rating for 380 MW: Final 220 kv cable system design as applied for HKZ Limitations due to the 380 kv cable system (not yet considered) Final curtailment level (lower than 90 C due to measuring uncertainty) As-is soil conditions deviating from geotechnical survey results Disclaimer: the content of this paper is disclosed for information purposes only. In no way does this paper constitute rights for (potential) Connected Parties, or bind TenneT legally. 20
Lay-out Platform
Jacket 19,5m 25m
Topside 19,5m 45m 25m Weight: 3350 tonnes
Technical Platform information package available upon request via: Netopzee@tennet.eu Field lay-out HKZ Jacket structure (including J-tube) Cable pulling methodology Cable deck 66 kv infield cable routing Plotplans Layout OWF control room OWF interface management Note: these documents are still in Basic Design and are subject to change. Memo on scour protection at HKZ via website: www.tennet.eu/netopzee
Field lay-out This drawing shows preliminary cable routes. These cable routes shall be the basis for further optimization during detailed design between TenneT, OWFs, Platform Contractor and Cable Contractors
J-tube These drawing shows preliminary J-tube designs. These design shall be the basis for further optimization during detailed design between TenneT, OWFs and Platform Contractor.
Cable pulling
Cable routing
OWF room
Scour protection
Scour protection 15m 15m 15m Memo on scour protection at HKZ via website: www.tennet.eu/netopzee 15m
Legal update
TenneT s offshore legal framework Min. Economic Affairs: Electricity Act, Wind Energy Act TenneT: offshore agreements ACM: offshore code TenneT: cooperation agreement - Realization agreement - Connection & Transmission agreement - eneral terms & conditions - Technical requirements to the offshore grid included in rid Code - With RWS for shared maritime information services
Offshore agreements HKZ Model agreements for connection to the Platform Hollandse Kust Zuid Alpha (HZA 1) Both a Realisation Agreement and a Connection & Transmission Agreement will be concluded per site: HKZ site I and HKZ site II respectively Dutch version is binding, English version for informative purposes if desired Since September 2016, several developments took place: Offshore ridcode established Agreement process with DON, Blauwwind
Realisation agreement Consideration B: Connected Party has been granted a Wind Farm Permit ( ) and as such entitled to a Connection to the Offshore Transmission System. 3.9 Offshore flexibility planning of activities - Connected Party submits a planning notice 8 weeks in advance - Connected Party informs TenneT on a weekly basis about progress - 2 weeks prior to the date, Connected Party informs TenneT on a daily basis to mutually assure sufficient progress and staff are available for the foreseen works to be carried out if the weather allows.
Realisation agreement 6.4 Project Working roup - PW will be established and act according to PW overnance Arrangements - PW will only cease to exist once Parties agree its activities can be ended. 6.5 - Project Working roup will discuss all matters related to a succesful, efficient and timely execution of both projects. 6.6 - PW will install working groups for more detailed discussion of practical arrangements - Topics may be: SHE Management, planning, administrative matters, technical matters
Realisation Agreement 11.2 Connected Party must notify TenneT regarding any Financial Investment Decision on the offshore wind farm taken 11.3 The Agreements are terminated if Connected Party withdraws the request for connection to the offshore grid
Connection & Transmission Agreement Consideration B: Connected Party is permit holder and as such entitled to a connection to the offshore grid. 5.5 Offshore flexibility planning of activities - Copied from REA in case Connected Party realises the OWF after the Connection has been realised 9.2 Article on establishment of Project Working roup has been deleted as this is already arranged in Realisation Agreement 14.2 Connected Party must notify TenneT regarding any Financial Investment Decision on the offshore wind farm taken 14.3 The agreements are terminated if Connected Party withdraws the request for connection to the offshore grid
Updates in Annexes Annex 3: Shared information systems TenneT aims to share (maritime) information systems on the Platform with the Connected Party and third parties where possible, in order to save on space, weight and power consumption. Rijkswaterstaat - CIV ("RWS") will organise and maintain these shared systems. TenneT has a role as assessor of technical feasibility of the systems on the Platform. Any costs related to these shared services will be settled between RWS and the Connected Party.
Updates in Annexes Annex 3: Individual information systems Connected Party may propose to install individual systems on the Platform for the purpose of individual use. TenneT will not unreasonably decline such a proposal. Amongst other considerations, the proposal may not compromise the basic principles of the shared information systems or compromise the realisation and operation of the Platform with respect to planning or technical and safety aspects. If the proposal is approved, TenneT will make available the provisions required for installation. Connected Party will install its own systems on the Platform as laid down in the table below. Connected Party will be the owner of the individual information systems and responsible for the correct functioning and maintenance of these systems.
Once the winner is known Clarification sessions with OWF and TenneT as needed Exchange of basic technical information, e.g.: Number of turbines, number of 66 kv cables, number of turbines per 66 kv cable Exchange of administrative information: Copy of subsidy grant letter Ministry of Economic Affairs Proof of mandate signing person Contact details legal entity, contact persons during realisation and operation Signing agreements Start Project Working roup with OWF and TenneT
Closing Q&A via netopzee@tennet.eu Prior to opening of the subsidy tender by the government, TenneT will provide publications via www.tennet.eu/netopzee 42
Disclaimer Liability and copyright of TenneT This PowerPoint presentation is offered to you by TenneT TSO B.V. ('TenneT'). The content of the presentation including all texts, images and audio fragments is protected by copyright laws. No part of the content of the PowerPoint presentation may be copied, unless TenneT has expressly offered possibilities to do so, and no changes whatsoever may be made to the content. TenneT endeavours to ensure the provision of correct and up-to-date information, but makes no representations regarding correctness, accuracy or completeness. TenneT declines any and all liability for any (alleged) damage arising from this PowerPoint presentation and for any consequences of activities undertaken on the strength of data or information contained therein.
www.tennet.eu TenneT is a leading European electricity transmission system operator (TSO) with its main activities in the Netherlands and ermany. With approximately 22,000 kilometres of high-voltage connections we ensure a secure supply of electricity to 41 million end-users. Taking power further