Halfdan is a significant oil and gas field in the south-western part of the Danish sector of the southern North Sea. The field has been in production since 1999. The Sif and Igor fields are satellites to Hallfdan.

Halfdan field
CountryDenmark
RegionNorth Sea
Location/blocks5505/13
Offshore/onshoreOffshore
Coordinates55.230115N 5.005754E
OperatorsTotal E&P Denmark.
OwnerTotalEnergies, Nordsofonden, and BlueNord.
Field history
Discovery1998
Start of production1999
Peak of production6.085 million cubic metres of oil
Peak year2006
Production
Estimated gas in place6.9×10^9 m3 (240×10^9 cu ft)
Producing formationsChalk

The field edit

The Halfdan field comprises the contiguous Halfdan, Sif and Igor fields in Blocks 5505/13 and 5505/16 of the North Sea.[1] The Sif and Igor fields are respectively to the north and east of the Halfdan field, but are exploited through the Halfdan offshore infrastructure.[1] The south west of the field contains oil of the Maastrichian layers and the north and east area has gas of the Danian era. Key parameters of the fields are given in the table.

Halfdan, Sif and Igor reservoir[1][2]
Parameter Value
Reservoir rock Chalk
Geological age Danian and Upper Cretaceous
Depth, ft 2030-2100
Discovery 1998
Field delineation, Halfdan 100 km2
Field delineation, Sif 40 km2
Field delineation, Igor 109 km2
Oil density 33° API
Oil reserves 35.9 million m3
Gas reserves 6.9 billion Nm3

Owners and operators edit

The Halfdan field is currently owned jointly by TotalEnergies, Nordsofonden, and BlueNord. It was formerly operated by Maersk and is currently operated by Total E&P Denmark.[3]

Production infrastructure edit

The Halfdan, Sif and Igor fields are exploited by three offshore installations Halfdan A, Halfdan B and Halfdan C, which were installed and came into operation sequentially. The A and B installations are manned multi-platform bridge-linked facilities. And Halfdan C is an unmanned satellite of the B complex.[4] Key parameters of the installations and platforms are given in the table.

Halfdan Installations[1][2][5]
Halfdan A Halfdan B Halfdan C
Block 5505/13 5505/13 5505/13
Name HDA HDB HDC HBA HBB HBC HBD HCA
Coordinates 55.230115N 5.005754E 55.537992N 5.030886E 55.557225N 5.134502E
Water depth, m 43 43 43 43 43 43 43 45
Commissioned 2000 2003 2003 2002 2008 2007 2011 2008
Type Fixed steel Fixed steel Fixed steel Fixed steel Fixed steel Fixed steel Fixed steel Fixed steel
Function Wellhead, processing Accommodation 32 beds Flare Wellhead, separation Riser, wellhead Accommodation 80 beds Processing Wellhead, separation
Wells 35 37 9
Bridges 2: each about 100 metre 3: 100 to 140 metre 0
Substructure weight, t 2800 1000 1150 3050 1800 2000 3500 1100
Topside weight, t 800 2200 500 2500 1380 3000 9300 630
Wells 35 37 9

Pipelines edit

In addition to the offshore installations there are a number of pipelines connecting and transferring fluids within the Halfdan field and to adjacent fields which act as oil and gas export routes.[1][2]  

Halfdan and connected pipelines
From To Fluid Length, km Diameter, inches Note
HDA HBA Gas, oil, water 1.7 12
HBA HDA Gas, oil, water 1.7 14
HBA Dan Gas, oil, water 11 20
Dan HDA Injection water 9 14
HDC HBA Gas 2 24
HCA HBB Gas 7 16
HCA HBB Oil 7 8
HDA Dan HP Gas 9 12
HDA Dan LP Gas 9 12
HDA Gorm Oil & condensate 19 14 Oil export route to shore
HBA Tyra West Gas 27 24 Gas export route to shore

Halfdan A and B have their own power supplies but are also interconnected. Halfdan C receives power from Halfdan B complex.[1]

Oil and gas production edit

Oil and gas from the reservoir are produced via a number of wells. In addition water injection is used to sweep oil towards the oil production wells.[1][2]

Wells edit

  • Oil production wells: 38 (Halfdan)
  • Gas production wells: 16 (Sif and Igor)
  • Water injection wells: 27 (Halfdan)

Plant capacity edit

  • The capacity of the plant on Halfdan A is: Oil 120,000 BOPD; Gas 120 MMSCFD; Produced water 115,000 BWPD.[2]
  • The capacity of the plant on Halfdan B is: Oil 90,000 BOPD; Gas 125 MMSCFD; Produced water 180,000 BWPD.[2]

Annual production and injection edit

Halfdan annual oil, gas and water production and water injection 1999-2013[6]
Year 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Oil production, 1000 m3 222 1120 2365 3718 4352 4346 6000 6085 5785 5326 5465 5119 4905 4617 4150
Gas production, million normal m3 37 178 522 759 1142 1449 2582 2948 2675 3104 3401 2885 2343 1709 1389
Produced water, 1000 m3 56 237 493 367 612 2099 2825 3460 4086 4766 4814 5519 6149 6139 6099
Water injection, 1000 m3 62 13 649 2532 5162 5759 9710 11026 12107 12727 11485 11945 12277 10912 10921
Halfdan annual oil, gas and water production and water injection 2014-22[6]
Year 2014 2015 2016 2017 2018 2019 2020 2021 2022
Oil production, 1000 m3 3674 3345 2780 2700 2385 2084 1733 1498 1433
Gas production, million normal m3 1309 1334 1191 1209 1203 1008 924 844 808
Produced water, 1000 m3 6574 7344 6709 7315 7190 7421 6879 6858 7452
Water injection, 1000 m3 11403 10760 8555 10032 8316 8823 8957 8716 8513

Future plans edit

Plans for future development of the field include: the Halfdan Ekofisk infills; HCA gas lift; Halfdan Tor NE infill; and Halfdan Northeast project.[3]

It has been estimated that the field will remain economically viable until 2035.[3]

See also edit

References edit

  1. ^ a b c d e f g "Danish Energy Agency" (PDF). 2014. Retrieved 7 November 2023.
  2. ^ a b c d e f "Maersk oil ESIA-16 Non-technical summary – ESIS Halfdan" (PDF). Retrieved 7 November 2023.
  3. ^ a b c "Oil & gas field profile: Halfdan North Conventional Oil Field, Denmark". 23 November 2021. Retrieved 7 November 2023.
  4. ^ "A Barrel full Halfdan oil and gas field". Retrieved 7 November 2023.
  5. ^ "OSPAR Inventory of Offshore Installations - 2021". Retrieved 7 November 2023.
  6. ^ a b Danish Energy Agency (15 August 2016). "Monthly and yearly production". Retrieved 8 November 2023.