Kriegers Flak (wind farm)

Summary

Kriegers Flak is a 605 MW offshore wind farm in the Baltic Sea on the Danish part of the reef of the same name.[1][2] It forms part of a new 400 MW interconnector between Denmark and Germany.

Kriegers Flak
Map
Country
  • Denmark
LocationBaltic Sea east of Møn, south of Skåne, north of Rügen
Coordinates55°04′N 13°01′E / 55.07°N 13.01°E / 55.07; 13.01
StatusOperational since September 2021
Construction beganMay 2018
Owner(s)
Wind farm
Type
Max. water depth25 m
Distance from shore15 km
Hub height107 m
Rotor diameter
  • 167 m (548 ft)
Site area179 km2 (69 sq mi)
Power generation
Units operational72 × 8.4 MW
Make and modelSiemens Gamesa SG 8.0-167 DD (72)
Nameplate capacity
  • 604.8 MW
External links
Websitehttps://en.energinet.dk/Infrastructure-Projects/Projektliste/KriegersFlakAC
CommonsRelated media on Commons
Map
Wind farm layout

Location edit

In 2010 the Danish Energy Agency pointed to the site as one of the most attractive for a Danish offshore wind farm.[1] In addition to favorable wind conditions and a depth ranging from 16 m to 25 m,[3] Kriegers Flak will also be located next to the German offshore wind farm ″EnBW Baltic 2″. Kriegers Flak will take advantage of this and be connected both to the Danish grid as well as to the 288 MW ″EnBW Baltic 2″ which is connected via the 48 MW ″EnBW Baltic 1″ to the German grid. The wind farm will consist of two partitions, a western of 200 MW covering 69 km2 (27 sq mi) and an eastern of 400 MW covering 110 km2 (42 sq mi); a sand dredging area separates the two areas.[3][4]

Combined Grid Solution edit

The Kriegers Flak Combined Grid Solution, a serial connection of offshore wind farms into the power grids of two different countries will be the first of its kind.[5] This has the advantage that up to the capacity of the connection the produced power can be transmitted to the country with the highest demand and price, improving the economy of the wind farms. Secondly, the connection between Denmark and Germany can act as an interconnector, so power can be transmitted from one country to the other, also in absence of power production from the wind farms themselves. This improves the overall reliability of the power grids in both countries[6] and can also reduce the overall price of the electricity.

The combined solution was scheduled to be direct current, but the offshore converter turned out to be prohibitively expensive,[7] and alternating current (AC) was chosen instead.[8][9] Like the 150 kV cables connecting the ″EnBW Baltic 2″, ″Baltic 1″ and Germany, the 170kV cables connecting Kriegers Flak to ″Baltic 2″[10] and the 220kV to Denmark will be relatively short and thus using AC which is more economical.[6][11] However, Germany is part of the synchronous grid of Continental Europe, while Kriegers Flak will connect to eastern Denmark, which is synchronized with the Nordic grid. As such, the non-synchronous connection requires a paired, back-to-back HVDC converter substation, to be located in Bentwisch, Germany, which already hosts the converter substation for the Kontek interconnector. The transmission capacity will be 400 MW, with the converter substation being delivered by ABB for around US$140 million.[5] Thus, when Kriegers Flak operates at its full 600 MW capacity at least one third of the produced power must be transmitted to Denmark.

The 220 kV cables to Kriegers Flak will be constructed and operated by Energinet.dk, with a planned spending of 3.5 billion DKK and planned commissioning by the end of 2018.[1][12] The cable will reach Denmark at Rødvig on Zealand.[3]

In June of 2019 NKT stated that they had successfully commissioned the 170 kV AC cable between Kriegers Flak and Baltic 2 and that the remaining 220 kV AC cable between Kriegers Flak and Denmark would become operational later in 2019.[13]

In November 2020, the European Union allowed the connection to transmit available wind power to shore rather than conform to the 70% market transmission rule.[14][15]

Tender edit

The result of a call for tenders for the construction of the wind farm was expected to be published by the end of 2016. By November 2015 seven companies and consortia had been prequalified to bid on the project; an unusually high number of bidders.[16]

The tender was won by Vattenfall in November 2016 at a fixed-price of €49.90 per MWh ($55.23 per MWh) with no adjustment for inflation, for 30 TWh (corresponding to 50,000 full-load hours for 600 MW, or about 11 years),[17] without the cost of the unusual transmission project. As of 2016, it is the lowest price for offshore wind. The price is 58% lower than the cap price of €0.12 (90 øre) per kWh set in 2012. Build cost is estimated at €1.1bn-€1.3bn[18] ($1.19–1.4 billion).[19] The turbines will be delivered by Siemens Gamesa, each yielding 8.4 MW.[20]

The low price was achieved by optimizing several aspects of the process, including the long-standing policy of authorities to prepare shovel ready projects with all necessary permissions. This method was also used in the previous low price record at Borssele where the price is €72.70 per MWh (€87 per MWh with transmission). The method contrasts with the British way of tender, where applicants must perform preparatory work.[17]

Construction edit

 
The construction site for the onshore substation in Rødvig in 2018

May 2018 saw installation of the three offshore converter stations that will transmit the electricity from the wind turbines to the onshore substations in Denmark and Germany[2] and in November 2018 its dual electric connection to the offshore station of EnBW Baltic 2 was successfully tested.[21]

While the construction at the Danish substation site was underway by August 2018, the construction of the similar German station in Bentwisch has been delayed by "a few months" so as of January 2019 the launch of the interconnector is planned for Q3 of 2019.[22]

Monopile foundations were being constructed in early 2019.[23] Turbines were prepared at the port of Rønne on Bornholm and put 4 at a time on a wind turbine installation vessel, then sailed to the site and erected. By April 2021, 36 turbines (half of the total 72) had been installed.[24] The wind farm became operational in the end of 2021.[16]

See also edit

References edit

  1. ^ a b c "Kriegers Flak Offshore Wind Farm". energinet.dk. Retrieved 2019-06-09.
  2. ^ a b "Offshore platforms for Kriegers Flak installed". en.energinet.dk. 2018-05-07. Retrieved 2019-06-09.
  3. ^ a b c "Kriegers Flak Havmøllepark" [Kriegers Flak Offshore Wind Farm] (PDF). energinet.dk (in Danish). January 2015. Retrieved 2016-08-22.
  4. ^ "Kriegers Flak". 4coffshore.com. Retrieved 2016-08-22.
  5. ^ a b Garus, Katharina (2016-03-14). "ABB gets order for Kriegers Flak onshore converter". ABB. Retrieved 2016-08-22 – via offshorewindindustry.com.
  6. ^ a b Wittrup, Sanne (2014-12-19). "Sjælland får ny, millliard-dyr elforbindelse til Tyskland". Ingeniøren (in Danish). Retrieved 2016-08-22.
  7. ^ Wittrup, Sanne (2014-03-12). "Hundedyrt at slutte havmølleparken Kriegers Flak til nettet". Ingeniøren (in Danish). Archived from the original on 12 March 2017. Retrieved 11 March 2017.
  8. ^ "Offshore wind turbines are connected to the electricity grid by traditional AC system". Energinet.dk. 5 June 2014. Retrieved 9 March 2017.
  9. ^ "Indstilling om tilladelse til etablering af ilandføringsanlæg for havmølleparken Kriegers Flak" (PDF) (in Danish). 12 December 2014. pp. 2–3. Retrieved 11 March 2017.
  10. ^ "NKT in Kriegers Flak Milestone". Subsea World News. 5 June 2019.
  11. ^ "The project". Energinet.dk. 29 April 2016. Retrieved 13 November 2016.
  12. ^ "Timeline". Energinet.dk. 5 November 2015. Archived from the original on 28 May 2017. Retrieved 13 November 2016.
  13. ^ Skopljak, Nadja (2019-06-05). "NKT Puts Kriegers Flak CGS Cable Into Operation". offshorewind.biz. Retrieved 2019-07-02.
  14. ^ "Kriegers Flak CGS Exempt From 70 Per Cent Rule". Offshore Wind. 17 November 2020. Archived from the original on 17 November 2020.
  15. ^ "derogation according to Article 64 of Regulation (EU) 2019/943" (PDF). 30 June 2020.
  16. ^ a b Garus, Katharina (2015-11-03). "Seven companies prequalified for Kriegers Flak". offshorewindindustry.com. Retrieved 2016-08-22.
  17. ^ a b Parr, Mike (2016-07-20). "Dutch and Danish Auction Model Heralds Bright Future for Offshore Wind". theenergycollective.com. Retrieved 2017-02-07. The tenderer is to quote a kWh price to be paid for 30 TWh (corresponding to 50,000 full-load hours for 600 MW). The price tendered is to be a fixed "øre" amount (constant in current prices) and will not be indexed.
  18. ^ "Vattenfall Wins Bid for Denmark's Largest Offshore Windfarm". The Maritime Executive. 2016-11-10. Retrieved 2017-02-07.
  19. ^ Williams, Diarmaid (2016-11-10). "More evidence of competitive wind power with Vattenfall's Baltic deal". powerengineeringint.com. Retrieved 2017-02-07.
  20. ^ "Om Kriegers Flak". 2018-07-04. Retrieved 2018-11-25.
  21. ^ "Successful test of offshore cables in the Baltic Sea". en.energinet.dk. 2018-11-08. Retrieved 2019-06-09.
  22. ^ "Few months delay in the construction of converter Station in Bentwisch". en.energinet.dk. 2019-01-24. Retrieved 2019-06-09.
  23. ^ "Construction of Kriegers Flak Offshore Wind Farm has started". www.windtech-international.com. 23 May 2019.
  24. ^ Foxwell, David (13 April 2021). "Jan De Nul reaches halfway point at Kriegers Flak". Riviera.

External links edit

  • Important documents and links Archived 2016-11-14 at the Wayback Machine Energistyrelsen
  • Technical Project Description, October 2015
  • Energinet project page Archived 2021-01-23 at the Wayback Machine (in Danish)