1. BACKGROUND MATERIAL SCOPE AND CONSIDERATIONS... 2

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1 POSITION PAPER STAKE HOLDER CONSULTATION PROCESS OFFSHORE GRID NL Type: Position paper Work stream Technical Topic: T. Overplanting Filename ONL T_Overplanting_PP_v3 Version 3 - Public release Pages 4 QUALITY CONTROL Prepared: Daniël Vree Reviewed: Frank de Vries Approved: Frank Wester Release Table of Contents. BACKGROUND MATERIAL SCOPE AND CONSIDERATIONS ACTIVE POWER TRANSFER THROUGH THE TENNET OFFSHORE GRID Export cable design (220kV) (Status V, dd ) ADDITIONAL CALCULATIONS ON DYNAMIC LOADING OF THE EXPORT CABLES Introduction (V ) Update based on results of initial geotechnical survey (V3)... 6 Analysis of soil data of the initial geotechnical survey... 6 Update of the dynamic ampacity calculations for 380MW: basis for the calculations... 7 Update of the dynamic ampacity calculations for 380MW: calculations results EXPORT CABLE LOAD MANAGEMENT POSITION OF TENNET IMPACT ON COST FURTHER UPDATES (STATUS AS OF ) ANNEX A: SOIL RESISTIVITY ANALYSIS - OFFSHORE CABLE ROUTE FROM LANDFALL TO BORSSELE ALPHA AND BETA... 4

2 PAGE 2 of 4. Background material Literature used: N.A. 2. Scope and considerations The Figure below shows a schematic cross section of the connection of an offshore wind farm to the onshore electricity grid. Wind turbines are connected through inter-array cables (in orange) to the offshore Connection Point (CP) at the offshore substation, from which electricity is transported to shore. TenneT is responsible for the grid connection up to, and including, the offshore substation and will take care for the supply and installation. The wind park, including the wind turbines and the array cables, up to the offshore CP at the switchgear installation on the offshore substation of TenneT, is to be supplied and installed by the owner of the Power Park Module (PPM 2 ). TenneT intends to standardise the offshore substations as much as possible for all five wind areas to be realised in the coming years in line with the Energy Agreement. Figure - Schematic of the offshore electrical grid. Source: TenneT The connection point (CP) between the offshore power park module (PPM) and TenneT is specified [TenneT position paper ONL 5-06 T.3 Point of Common Coupling] at the cable termination of the inter-array cables and the switchgear installation on the platform. 2 TenneT, position paper ONL T.5 Operation of Bays

3 PAGE 3 of 4 Overplanting An important aspect in the design of an offshore wind farm, is to optimise the offshore wind farm capacity (type and number of wind turbine generators) to the fixed electrical infrastructure export capacity. This principle is also referred to as overplanting or overbooking since it usually leads to installing a (small) number of extra wind turbine generators compared to the grid connection capacity limit 3. The "overplanted" power from these extra turbines will result in higher energy yield at lower wind speeds but will lead to a curtailed power at higher wind speeds as depicted in Figure 2. Off course, the extra turbines will result in higher CAPEX, which should be balanced by extra revenues from the extra energy yield. Figure 2 - Principal of Capacity Optimisation. Source: Global Offshore Wind Conference 204. To be able to further optimise the PPM lay-out (location, type and number of wind turbine generators), it is necessary for the PPM owner not only to know to what to extent the grid connection may be continuously loaded (e.g. the grid capacity limit) but also to what extent the grid connection may be (temporary) loaded above this capacity limit. In this way, the curtailed power is reduced and the energy yield is increased further. This paper describes the position of TenneT with respect to the extent to which the offshore grid (see Figure ) may be loaded more than the rated power at CP and under which conditions. As the limiting factor in the offshore grid is the 220 kv export cable from the offshore substation up to and including the beach landing, this paper will mainly focus on these cables. 3 Money does grow on turbines Overplanting Offshore Windfarms, Andrew Henderson a.o., Global Offshore Wind Conference 204

4 PAGE 4 of 4 3. Active power transfer through the TenneT offshore grid The offshore grid design will be based on the parameters as listed in Table. Table - TenneT NL offshore grid parameters Grid parameter Value Grid capacity per PPM at offshore CP: 350MW Number of PPM per offshore platform: 2 Reactive power exchange at CP under normal conditions: Max +/- 0, p.u. (+/- 35 Mvar) Nominal voltage level onshore / offshore: 225 / 230kV +/- % To determine if more than 700MW (2 * 350MW) of active power (P) can be transferred through the offshore grid, TenneT makes an assessment of the capability of the 220 kv export cables (next paragraph) based on the parameters shown above. If there is additional capacity found in the design which allows the 220 kv export cables to transfer more than 700MW of active power, TenneT will assure that other grid components will also be capable to transfer this extra power. According to RfG, PPMs will be required to contribute to the primary voltage regulation with more reactive power than shown in Table. It is assumed that these circumstances (Q > 35Mvar or Q < -35Mvar) will be limited in time and therefore will not significantly influence the thermal loading of the cables. 3. Export cable design (220kV) (Status V, dd ) A preliminary 220 kv export cable design study was commissioned by TenneT for a capacity of 700MW in steady state condition according to the IEC Although the exact soil conditions are not yet known, the results of this design show that under a wide range of the thermal resistivity of the soil, typical cable designs are available. Furthermore, within this study dynamic load calculations on the 220 kv export cables have been performed using actual wind data over a measuring period of three and a half years. The calculations have been used to assess possibilities for optimisation of cable dimensioning. The calculations are based on various cable types (variation in conductor type and cross section), a range of thermal resistivity values of the soil and two different installation locations (near offshore platform at one meter under seabed and near shore at three meters under seabed). The results of the dynamic load calculations show that for an optimized cable design (at 700MW design capacity), the transmission of 0% additional active power is allowable, but not guaranteed, provided the following conditions are met: - Voltage at nominal voltage as defined in Table ; - Soil resistivity over the whole trajectory 0,7 K.m/W as a maximum Simulation results show that on a few occasions the maximum allowable conductor temperature would be exceeded and curtailment is necessary (provided that all wind turbine generators are in operation). These

5 PAGE 5 of 4 results are shown in Figure 3. Further analysis of these results show that from the simulated hours, the conductor temperature is 643 hours above 90 C (2,4%). A more detailed forecast on risk of curtailment will be made by TenneT when soil conditions are known and the basic design of the cable is available. Figure 3 - Thermal behaviour of one of the 220 kv export cables (preliminary design) at two thermal resistivity values at the beach with a wind farm installed power of 770MW. 4. Additional calculations on dynamic loading of the export cables 4. Introduction (V ) The duration in hours that a load of 380MW can be transferred through one of the export cables before curtailing of output power of the wind park will take place is dependent on the following factors:. Temperature of the cable before the 380MW limit is reached. This temperature is again dependent on the loading history of the cable the previous hours or even days. This again is directly related to the wind speed; 2. The method of curtailing of which preliminary information is given below; 3. Final soil resistivity values over the complete cable route; 4. Final design of the cable system; 5. Voltage level of the system. A clear and binding answer on the question of duration before curtailing will occur can't be given due to e.g. soil resistivity which will only be determined on a limited set of samples and the power output of the wind farms.

6 PAGE 6 of 4 However, TenneT made dynamic loading capability calculations based on assumptions on wind speeds, soil resistivity and cable design. In this position paper and V 4 some results of these calculations have been given 5. When soil resistivity measurement results (which are part of the geotechnical survey) are available to TenneT, TenneT will update its calculations for the Borssele case which will lead to a better estimate. This update is expected to be finished end of January 206. Within these calculations, the following calculations will be made for the worst case location on the cable route (hot spot):. Time until the conductor reaches 90 C at 380MW load with a starting conductor temperature (t=0) related to a continuous loading of the cable before (t<0) of 350MW and 0MW; 2. Time until the conductor reaches 90 C at 365MW load with a starting conductor temperature (t=0) related to a continuous loading of the cable before (t<0) of 350MW and 0MW. These simulation results (which are still estimates) can be used in the business case calculations of the offshore wind park developers. 4.2 Update based on results of initial geotechnical survey (V3) Analysis of soil data of the initial geotechnical survey In January 206 the final report of the first geotechnical survey has been received by TenneT. The final report ['Factual Report Geotechnical Investigation, '] is available on request via netopzee@tennet.eu. In this survey 5 boreholes are included with a target depth of seabed 6m including measurements of the thermal conductivity of 0cm samples per each m. Most boreholes ended between seabed 5m and seabed 6m. The raw data of this final survey report has been processed where for each borehole the effective thermal resistivity value (G) has been determined on the target depth of burial (DOB) using the conformal mapping methodology as stipulated in [Cigré ELECTRA nr 98, The calculation of the effective external thermal resistance of cables laid in materials having different thermal resistivities, 985]. These effective thermal resistivity (G) values are included in Annex A. The target DOB per route section (which can also be found in the table of Annex A) has preliminary been determined by TenneT based on expected permit requirements and preliminary results of the morphological study and may change during the ongoing route engineering works. Based on the data of the final survey report and Annex A, the areas with the highest thermal resistivity values have been listed in Table 2, where also a short description is included per area. 4 T_Overplanting_PP_v.pdf 5 KNMI measuring pole 32 Europlatform (coordinates 0044; ), measuring dates until , data was converted from 29.m height to a height of 07m.

7 PAGE 7 of 4 Table 2 Areas with highest thermal resistivity values along the Borssele cable route Location Target Effective G Description DOB [m] [K.m/W] Mudflats 3,6 The thermal resistivity which is found in the mudflats area is the result of layers of peat and clay. If the target DOB would be decreased to,2m (land equivalent), the effective resistivity value will decrease to,3 K.m/W. Spijkerplaat 20 0,7 At this moment, an estimate of the effective thermal resistivity on 20 meters has been assumed. Although the target DOB in the Spijkerplaat is now preliminary set at 0m, the morphological study indicates that in the future a coverage up to 20m can be expected and this value has to be taken into account in the cable design. Rede van Vlissingen 6 0,8 At KP-KP3 layers of clay have been identified at the southern part of the cable route. Only limited measurements are available (on route BH92 and off-route BH, BH2), but based on these measurements, clay must be taken into account which results in the given thermal resistivity value. West of Botkil 0,9 In this area clayey soil has been found. Offshore below sand wave 8 0,5 Based on the current survey data, effective thermal resistivity on the bottom of the sand wave is estimated to be 0,5 [K.m/W]. Due to the migration of sand waves and as the cables will be installed at a level below the bottom of these sand waves, cables may in the future be covered by a full sand wave with heights up to 8m. The areas of Table 2 are shown on a map in Figure 4. West of Botkil West slope of Rede van Vlissingen Mudflats Figure 4 Locations of Table 2 on the map

8 PAGE 8 of 4 Update of the dynamic ampacity calculations for 380MW 6 : basis for the calculations Soil conditions In the previous issue of this position paper the following assumption was made on the thermal resistivity along the cable route: - Thermal resistivity over the whole trajectory 0,7 K.m/W as a maximum From Table 2 it can be concluded that this is not the case in three of the areas (Mudflats, Rede van Vlissingen, West of Botkil). Also the future coverage of 20 meters at the Spijkerplaat was not taken into account at that time. Below it is described how the new results are taken into account in the basis for the dynamic ampacity calculations of this update. As currently a) cable/route engineering is still in progress and b) an additional survey is being carried out, this basis for calculation may change significantly. Therefore, this update is only an intermediate update where in some cases no calculations have been done (Mudflats) or calculations for two different scenario's (Spijkerplaat / Rede van Vlissingen). See chapter 8 on when the final update will become available. Mudflats: The thermal resistivity of the mudflats area is so high that backfill must be considered. Backfill is a mitigating measure where thermal resistivity is improved by embedding the cable in sand with a better thermal resistivity value than the original soil. At this moment, the feasibility of this option is under investigation., both technically as permit wise. Therefore, this area has not been taken into account within this update of the dynamic ampacity calculations, but will be taken into account in the final update. However, at this moment it is expected that with the right backfill design, ampacity issues can be mitigated. Spijkerplaat: The value in Table 2 of the effective thermal resistivity of the extreme future burial condition at the Spijkerplaat of 20 meters has been used as the basis for the dynamic ampacity calculations of this update. When results of the current survey (see chapter 8) will become available, the effective thermal resistivity value for this case will be calculated from actual soil measurements and may then change significantly. Therefore, the results of the calculations on this area must be treated as preliminary. As an example, also calculations for an effective thermal resistivity of 0,6 K.m/W have been made. Rede van Vlissingen: At the areas where clay has been found, the target DOB will be decreased to the minimum DOB required by permit which is seabed 3m for this area. For this area both of the following cases have been used as a basis for the dynamic ampacity calculations: - DOB of 6m with effective G-value of 0,8 [K.m/W] (original case of Table 2) - DOB of 3m with effective G-value of 0,7 [K.m/W] (case with following assumptions: a) DOB is decreased, b) trench will be dredged and c) sand will be used for filling the dredged trench). West of Botkil / sand waves: For the offshore part of the cables the West of Botkil area was determined to be the worst case situation based on the (static) ampacity calculations for 350MW and has been used for this update of the dynamic ampacity calculations. 6 In V3 of this position paper, the maximum power of 380 MW is aligned with the development framework for the offshore grid as prescribed by the Ministry of Economic Affairs

9 PAGE 9 of 4 The above scenario's are summarized in Table 3. Table 3 - Calculation scenario's used for update 0 of the dynamic ampacity calculations West of Botkil Rede van Vlissingen Spijkerplaat DOB = m DOB = 3m DOB = 6m DOB = 20m G = 0,9 G = 0,7 G = 0,8 G=0,6 G = 0,7 Scenario 380. Scenario Scenario Scenario Scenario Cable design Load Flow For cable properties which have an impact on the load flow, following values have been assumed for the dynamic ampacity calculations of this update: - Capacitance of cable: 0,22 µf / km (mean value) - Length of cable: 67 km (Borssele Beta, worst case) This results in a full load current (350 MW) at the land station side of 925A and an overload current (380 MW) of 000 A. Also, an additional preloading condition of 67% has been taken into account of 70 A 7. Variance of capacitance will lead to a variance of full load current (350 MW) in the range of 5A around the above stated current of 925 A. For Borssele Alpha with a route which is 7km less, the full load current (350 MW) will be reduced with about 0A. The reactive power compensation at full load is assumed to be 50%/50% onshore and offshore. The reduction of capacitive current in the cable further from platform or land station has not been taken into account in the dynamic ampacity calculations of this update. Losses In the previous versions of this position paper (V / V2), the provided calculation results were based on a general and preliminary 600mm2 AL (aluminium) conductor cable design not related to any specific cable manufacturer. In this update of the dynamic ampacity calculations, the same 600mm2 AL cable design is used as a base case. If static ampacity calculations on 350MW showed that this design would not reach the required static ampacity, a general and preliminary 600mm2 CU (Copper) cable design has been used instead. For both designs, on other cable properties which have an impact on the losses (apart from conductor design), following assumptions have been used: - Armour design: galvanized steel wires with λ2 factor according to IEC (worst case); - Cable (core) lead sheath: common value for thickness of the sheath and λ factor according to IEC (average value) 7 This current is higher than 67% * 925 A as at lower currents, the 50%/50% compensation scheme is shifting towards a higher current at land station side. This higher current in the loadflow has been used here.

10 PAGE 0 of 4 J-tube The J-tube is not found to be a critical part of the cable system. With the base case of 600mm2 AL, the steady state rated current in the J-tube is well above 000 A. This is based on the following conditions: - Wind speed of > 0 m/s; - Solar radiation of 602 W/m2 (max intensity of 000 W/m2 and an angle of 53 ); - Ambient temperature of 30 C. Grid connection limitations With respect to the overloading of the grid connection system, the 380 MW shall be seen as an absolute maximum as other grid components such as the main transformers have much shorter thermal time constants. If more than 380 MW is being generated by the WPO, the curtailment level 3 is applicable as described in chapter 5 (actual curtailment of the power output of the wind park by TenneT). In this case a certain time delay will be taken into account which will be related to the amount of exceedance of the 380 MW limit. Update of the dynamic ampacity calculations for 380MW: calculations results In V2 of the position paper, following was stated (see paragraph 4.): Within these calculations, the following calculations will be made for the worst case location on the cable route (hot spot):. Time until the conductor reaches 90 C at 380MW load with a starting conductor temperature (t=0) related to a continuous loading of the cable before (t<0) of 350MW and 0MW; 2. Time until the conductor reaches 90 C at 365MW load with a starting conductor temperature (t=0) related to a continuous loading of the cable before (t<0) of 350MW and 0MW In this update of the dynamic calculations, only the 380MW case has been studied, but five scenario's instead of one scenario have been assessed as well as three different preloading conditions (instead of two). The preloading condition of 67% / 70 A has been added to reflect an average loading of the cable which may be expected over a long time with a wind farm loading profile. Also, a preloading time of one year has been used for the 67% and 00% conditions to assure a starting temperature which is nearby the steady state conductor temperature when calculated according the IEC The dynamic calculations for this update have been made according to the IEC

11 PAGE of 4 The results of the calculations are given in Table 4 where the time until the conductor reaches 90 C is stated in hours. Table 4 - Time (in hours) for conductor to reach 90 C at 000 A with three preloading conditions for five scenario's % Preloading # of Preload I days [A] Scenario 380. Scenario Time to reach 90 C [hours] Scenario Scenario Scenario % n/a > 8760 > % % West of Botkil Rede van Vlissingen Spijkerplaat DOB = m DOB = 3m DOB = 6m DOB = 20m G = 0,9 G = 0,7 G = 0,8 G=0,6 G = 0,7 For the scenario's following conditions have been used: - Scenario 3 and 5: 600mm2 CU conductor - Scenario, 2 and 4: 600mm2 AL conductor - Scenario, 2: ambient temperature 5 C - Scenario 3, 4,5: ambient temperature 0 C - Overloading: 380MW, Current I [A]: 000 A 5. Export cable load management In general, TenneT identifies three levels in the export cable load management process:. Alignment of the wind park owner's (WPO) generation forecasts to dynamic cable loading capabilities; 2. Actual curtailment of the power output of the wind park by the WPO; 3. Actual curtailment of the power output of the wind park by TenneT. Ad It is the responsibility of the WPO to align its forecasts to possible curtailment of the wind park power output due to the temperature limit of the export cables (only if wind park power output is higher than the guaranteed 350 MW). To facilitate this alignment process, TenneT will provide: a) calculation results as described above (updated on the as-built situation); b) the actual cable conductor temperature measurements (data format and frequency to be defined in a later stage).

12 PAGE 2 of 4 Ad 2 If the conductor temperature will increase above a certain threshold value (value to be determined per project), WPO will receive a warning signal from TenneT. WPO shall start at that moment (at the latest) with the curtailment of the wind park power output, down to 350MW. If this curtailment is not started or is not sufficient and conductor temperature will increase above a second threshold value (close to but below 90 degrees Celsius, to be determined per project), WPO will receive a second and final warning signal from TenneT. Immediately after this second signal has been released, TenneT has the right to proceed to the third level as described below. The warning signals are considered to be the official legally binding information provided by TenneT to the WPO. The cable conductor temperature measurements as described under level are provided by TenneT as an extra service and will be for information only. Ad 3 When the second warning signal has been released, WPO shall immediately reduce the power output to a maximum of 350 MW. TenneT will at that time monitor conductor temperature and power output continuously. If the reduction of power by the WPO is not sufficient, TenneT will have the right to curtail under 350MW by switching off one of the strings of the wind park without any further notice. With the three levels described above, an export cable load management process has been introduced that enables the WPO to manage its generation forecasts and actual power output curtailment while at the other hand it is assured that the export cable conductor temperature will never increase above 90 degrees Celsius. 6. Position of TenneT Above considerations lead TenneT to the following position: TenneT is inclined towards allowing the PPMs to transmit 8% above their rated power (350MW), which is 30MW extra, with the requirement for PPM's to curtail their produced power, in case the 220 kv export cables reach their maximum allowable temperature limits 8. Details on curtailment of the PPMs will be addressed to in the 'Customer Connection Agreements (ATO)'. The calculations results of paragraph 4.2 are only valid for Borssele. For the Hollandse Kust (Zuid) tender, TenneT will give an update based on specific Hollandse Kust (Zuid) soil data. TenneT has decreased the allowed additional rated power from 0% (V2) to 8% (V3) in order to align this allowable addition with the development framework for the offshore grid as prescribed by the Ministry of Economic Affairs. 8 Operational limits of sea and land cables will be monitored continuously by temperature sensing systems.

13 PAGE 3 of 4 7. Impact on cost At this point in time the impact on costs cannot be analysed quantitatively, as this requires detailed knowledge (assumptions) on both wind farm layout, turbine choice and dynamic loading strategies. 8. Further updates (status as of ) At this moment a second survey is being carried out for additional information on thermal resistivity due to the following reasons: - Determination of thermal resistivity in highly mobile areas (Spijkerplaat, Nollenplaat) up to a depth of 0m (Nollenplaat) and 20m (Spijkerplaat); - Better assessment of the other areas listed in Table 2: West of Botkil and Rede van Vlissingen. The results of this additional survey will be used for a final update of this position paper. Also, 365 MW scenario's will be included in that update. This update is expected first half of April 206.

14 PAGE 4 of 4 9. Annex A: Soil resistivity analysis - Offshore cable route from landfall to Borssele Alpha and Beta Table with effective soil resistivity values.

15 Nearshore borehole locations Subsection From KP to KP km km m Northern slope Honte 0,7,3 North slope Honte to shore Honte Navigational Channel,3,8 Honte fairway Southern slope Honte,8 3,0 Slope fairway to Spijkerplaat -0m Spijkerplaat 3,0 6, Spijkerplaat from LAT-0m to -0m Rede van Vlissingen 6,,6 Between LAT-0m Spijkerplaat to Rede v. Vl Rede van Vlissingen 6,,6 Rede van Vlissingen Section Navigational channel Westerschelde / South of Nollenplaat,6 3,6 Remainder west slope Rede v.vlis-nolleplaat Nollenplaat 3,6 6,6 Nolleplaat Deurloo 6,6 27,8 Deurloo Rassen 27,8 32,3 Rassen Kaloo to LAT -0m 3) 32,3 35,6 Between Rassen and LAT-0 m length Depth of installation Point-ID Easting Nording Comment Thermal resistivity [K.m/W] Remarks 3 8-PC ,39 Conformal mapping 3 9-PC ,62 Conformal mapping 3 20-PC ,34 Conformal mapping 3 7-PC ,44 Average <3m 3 07-VC ,70 Average. Meas <2,2m VC ,70 Average. Meas <,5m VC ,45 Conformal mapping 3 08-VC Offroute but possibly required 0,65 Average. Meas <,7m 3 09-VC ,47 Conformal mapping VC ,53 Conformal mapping Average < 5,3 m, 0 066A-VC Effective G value on 5m 0,45 No samples>5m Average < 5,6 m, 0 076a-PC Effective G value on 6m 0,48 No samples>5m Average < 5,0 m, VC Effective G value on 6m 0,43 No samples>5m VC Effective G value on 6m 0,49 Conformal mapping 0 Average < 5,6 m, 02-PC Effective G value on 6m 0,45 No samples>5m 0 Average < 5,6 m, 03-PC Effective G value on 6m 0,43 No samples>5m 0 Offroute but possibly required Average < 5,6 m, 04b-PC Effective G value on 6m 0,45 No samples>5m 0 Average < 5,6 m, 0b-PC Effective G value on 6m 0,50 No samples>5m 0 Average < 5,6 m, 00-PC Effective G value on 6m 0,47 No samples>5m 0 06-VC Effective G value on 5m 0,46 No samples > 5m VC ,43 Average VC ,46 Average 6 3-VC ,45 Average VC ,48 Conformal mapping Borehole is off-route. It is not clear if layers of 6 2-VC clay extend to actual cable route 0,76 Conformal mapping VC ,45 Conformal mapping VC ,60 Conformal mapping VC ,5 Conformal mapping VC ,44 Average VC ,40 Conformal mapping VC ,4 Average <4m 3 085a-VC ,40 Average <4m VC ,4 Average <4m VC ,4 Average <4m 3 05-VC ,64 Conformal mapping VC ,4 Conformal mapping VC ,47 Conformal mapping VC ,48 Conformal mapping VC ,5 Conformal mapping VC ,67 Conformal mapping VC ,52 Conformal mapping VC ,45 Conformal mapping VC ,53 Conformal mapping VC ,37 Conformal mapping VC ,59 Conformal mapping VC ,46 Average 3 04-VC ,63 Conformal mapping VC ,39 Conformal mapping VC Effective G value for 3m 0,43 Average <2, VC ,43 Conformal mapping VC ,42 Conformal mapping VC ,7 Conformal mapping VC ,4 Conformal mapping VC ,55 Conformal mapping VC ,62 Conformal mapping VC ,49 Conformal mapping

16 Offshore borehole locations Section Subsection From KP Depth of length installation to KP km km m Point-ID Easting Nording Comment Thermal resistivity [K.m/W] Remarks 2 LAT -0m up to West Rond Route 3) 35,606 46,79 West of Botkil LAT -0m up to West Rond Route 3) East slope Steendiep LAT -0m up to West Rond Route 3) Steendiep LAT -0m up to West Rond Route 3) Rabsbank West Rond Route 3) 46,79 50,7 Shipping route over West-Rabsbank West Rond Route up to platform location 3) West Rond Route up to platform location 3) West Rond Route up to platform location 3) West Rond Route up to platform location 3) Between platform Alpha and platform Beta 3) 50,7 67,469 West slope Rabsbank Sandwave area Buitenbanken Sandwave area ,469 67,469 Area just before Platform Beta VC Layer of clay,,2 meter (0,2-,4m) 0,83 Conformal mapping 03-VC ,66 Conformal mapping 094-VC No wet density samples analyzed n.n. Value at -m 030-VC ,42 Value at -m 029-VC ,54 Value at -m 028-VC ,50 Value at -m First layer (0,8m): sand with high resistivity value (0,8). Data from DB/calculation, no 027-VC measurement 0,6 Conformal mapping 026-VC ,35 Value at -m 025-VC ,47 Value at -m 024-VC ,45 Value at -m 099-VC ,32 Value at -m 073A-VC On two depths (possibly sand wave) 0,56 Average of first 2 layers On two depths (possibly sand wave) 0,49 Conformal mapping 023-VC On two depths (possibly sand wave) 0,45 Value at -m On two depths (possibly sand wave) 0,42 Conformal mapping 022-VC ,37 Value at -m 02-VC ,4 Value at -m 020-VC ,39 Value at -m 09-VC ,39 Value at -m 08-VC ,5 Value at -m 07-VC ,44 Value at -m 06A-VC ,39 Value at -m 05-VC Bottom of sand wave (-34,7) 0,49 Conformal mapping 095-Vca Bottom of sand wave (-33,8m) 0,55 Conformal mapping Average <2,5m ,38 No meas >-2,5, 04-VC Average <4m On two depths; In between sand wave 0,38 No meas >-2,5, 03-VCa On two depths; Near sand wave 0,43 Value at -m ,5 Conformal mapping 02-VCa On two depths; Near sand wave 0,45 Value at -m ,4 Average <3,6m Average<2m 096-VCa ,40 No meas.<-2m On two depths; Top of sand wave. Depth Average<2m of hole only 2,5m though. 0,40 No meas.<-2m 0-VC ,34 Value at -m 00-VC ,4 Value at -m 009-VC ,37 Average <2,5m, ,37 Average <2,5m ,40 Average <2,5m 008-VC 4,5 In between sand wave (-25,5m) Average <3,5m ,42 No meas <-3,5 m 007-VC ,45 Average <2,8m In between sand wave (-24m) 0,45 Average <2,8m ,48 Average of first 2 layers,5 006-VC Near bottom of sand wave 0,48 Average of first 2 layers 2, ,58 Conformal mapping 005-VC Near bottom of sand wave 0,42 Value at -m (one meas. disregard ,47 Conformal mapping 004-VC ,40 Value at -m In between sand wave 0,40 Average <4m 003-VC Bottom of sand wave 0,45 Value at -m ,45 Conformal mapping 002-VC Bottom of sand wave 0,40 Value at -m ,48 Average<3m 2 00-VC In between sand wave 0,48 Average<3m In between sand wave 0,44 Average<4m