Azeri-Chirag-Deepwater Gunashli
Azeri-Chirag-Deepwater Gunashli (ACG) field located about 100km east of Baku is the largest oilfield in the Azerbaijan sector of the Caspian basin
BP Exploration (Caspian Sea) Limited is the operator on behalf of the Contractor Parties to the ACG Production Sharing Agreement.
In 2025, bp and its co-venturers spent about $564 million in operating expenditure and about $1,288 million in capital expenditure on ACG activities.
During the year, the 4D high-definition ocean bottom node seismic programme on ACG successfully completed processing of the data acquired in 2024 and concluded data acquisition for the second year of the programme.
In addition, ACG has launched a multi-well subsea intervention campaign in the Deepwater Gunashli (DWG) area. For the first time in bp’s Caspian operations, the campaign is deploying riserless light well intervention (RLWI) technology – a subsea mechanical wireline intervention system known as the Blue Ocean Riserless Intervention System (BORIS), provided by Oceaneering International.
Production
During the year, ACG continued to safely and reliably deliver stable production. Total ACG production for the full year was on average about 330,000 barrels per day (b/d) (about 120 million barrels or 16 million tonnes in total) from the Chirag (21,000 b/d), Central Azeri (90,000 b/d), West Azeri (76,000 b/d), East Azeri (43,000 b/d), Deepwater Gunashli (51,000 b/d), West Chirag (24,000 b/d) and ACE (25,000 b/d) platforms.
In 2025, ACG marked two major production milestones. On 18 February, the Central Azeri platform celebrated the 20th anniversary of first oil production. The platform remains the leading ACG production facility having produced a total of 1.2 billion barrels (157 million tonnes) of oil to date. Later in the year, on 30 December, the West Azeri platform also marked 20 years since first oil, with total cumulative production exceeding 1 billion barrels (142 million tonnes).
At the end of 2025, 147 oil wells were producing, while 49 were used for water and 10 for gas injection.
Drilling and completion
In 2025, ACG drilled and completed 10 oil producer, five water injector, one gas injector and one cuttings re-injector wells.
Associated gas
During the year, ACG delivered an average of around 8 million cubic metres per day of ACG associated gas to the state of Azerbaijan (2.9 billion cubic metres in total), primarily at the Sangachal terminal but also to SOCAR’s Oil Rocks facility. The remainder of the associated gas produced was re-injected for reservoir pressure maintenance.
Non-associated gas (NAG)
Following the signing of the ACG NAG Addendum in 2024, an initial production well was planned and safely drilled from ACG’s existing West Chirag platform. The well also represents a significant appraisal milestone, as the data obtained will help build future plans for ACG’s NAG development.
In 2025, the well was successfully delivered, providing access to two priority NAG deep reservoirs - the shallower NKP and the deeper PK reservoirs - both located beneath the currently producing oil reservoirs.
The well confirmed the presence of gas resources in the NKP reservoir, which is the main target reservoir for first NAG production, starting second half this year.
Additionally, the well encountered high pressure gas in the PK reservoir. There are also plans to produce from this reservoir in the first half of 2026, however, production from PK will be short-term and undertaken solely for testing purposes, before we move to the NKP reservoir.
ACG platforms
Chirag is an offshore production, drilling and quarters (PDQ) platform located 120km east of Baku in the Caspian Sea, at a water depth of 120 metres . The platform has been in operation since 1997 producing the so-called Early Oil from the ACG field.
Chirag facilities include:
- 24-slot PDQ platform with water injection equipment
- 24-inch oil pipeline to the receiving terminal at Sangachal
- 48km long 16-inch gas pipeline to the Oil Rocks
- 18-inch gas pipeline to Central Azeri
The Chirag platform has both producing and water injection wells to handle water injection to increase oil recovery.
Total Chirag production for the first three quarters of 2025 was on average about 21,000 barrels per day.
On 9 March 2010, the Steering Committee for the development of the Azeri, Chirag and deepwater portion of the Gunashli (ACG) fields sanctioned investment in the new Chirag Oil Project (COP). The $6 billion development plan was the next major step in the ongoing development of the ACG field in the Azerbaijan sector of the Caspian Sea. The project was planned to increase oil production and recovery from the ACG field through a new offshore facility – West Chirag platform, which was designed to fill a critical gap in the field infrastructure between the existing Deepwater Gunashli (DWG) and Chirag platforms.
West Chirag(WC) is an offshore production, drilling and quarters (PDQ) platform located at a water depth of about 170 metres between the existing Chirag and Deepwater Gunashli platforms.
West Chirag facilities include:
- 48 slot PDQ
- 14-inch gas pipeline
- 30-inch oil pipeline
On 28 January 2014 WC production began from one of the pre-drilled wells - J05. The oil first passed through the newly installed processing facilities on the platform and then was exported to the Sangachal Terminal via a new in-field pipeline linked to an existing 30” subsea export pipeline. Production increased as the other pre-drilled wells were brought on line.
Total WC production for the first three quarters of 2025 was on average about 24,000 barrels per day.
East Azeri (EA) is an offshore production, drilling and quarters (PDQ) platform located 100km off Baku coast in the Caspian Sea, at 152 metres of water depth. The platform has been been in operation since 2006 producing oil from the eastern part of the ACG field.
East Azeri facilities include:
- 48-slot PDQ platform.
- 22-inch gas pipeline from EA directed to Central Azeri platform.
- 30-inch oil pipeline tied in Phase 2 (from Central Azeri to Sangachal terminal).
Total EA production for the first three quarters of 2025 was on average about 43,000 barrels per day.
Azeri Central East (ACE) is an offshore production, drilling and quarters (PDQ) platform located midway between the existing Central Azeri and East Azeri platforms in a water depth of 137 metres. The platform has been in operation since April 2024.
Azeri Central East facilities include:
- 48-slot PDQ platform
- new infield oil and gas transfer pipelines
Total ACE production for the first three quarters of 2025 was on average about 24,000 barrels per day.
Central Azeri (CA) is an offshore production, drilling and quarters (PDQ) platform located 100km east of Baku in the Caspian Sea at a water depth of 128 metres. The platform has been in operation since February 2005 producing oil from the central portion of the ACG field.
In addition to the PDQ, a compression and water injection platform (C&WP) is installed in Central Azeri and bridge-linked to the PDQ to create a major offshore complex encompassing accommodation, drilling, production, processing, compression and re-injection facilities. C&WP provides water and gas injection services to the Central, West and East Azeri platforms, manage associated gas export and provide electrical power using 10 Rolls Royce turbines.
Central Azeri facilities include:
- 48-slot PDQ platform
- C&WP platform
- 30-inch oil pipeline from CA to the Sangachal terminal
- 28-inch gas pipeline from CA to the Sangachal terminal
- expansion of the existing onshore terminal at Sangachal
Total CA production for the first three quarters of 2025 was on average about 88,000 barrels per day.
West Azeri (WA) is an offshore production, drilling and quarters (PDQ) platform located 100km off Baku in the Caspian Sea at a water depth of 120 meters . The platform has been in operation since December 2005 producing oil from the western portion of the ACG field.
West Azeri facilities include:
- 48-slot production, drilling and quarters (PDQ) platform
- 30-inch oil pipeline from WA to the Sangachal terminal
WA oil production began from the first of the three pre-drilled
production wells on 20 December 2005. On 4 January 2006 WA oil reached the Sangachal terminal.
Total WA production for the first three quarters of 2025 was on average about 75,000 barrels per day.
Deepwater Gunashli (DWG) complex is the third phase of development of the ACG field in the Azerbaijan sector of the Caspian Sea. it is located on the east side of the Gunashli field at 175 metres of water depth. The platform has been in operation since April 2008 producing oil from the ACG field.
The complex comprises of two bridge-linked platforms:
- 48-slot drilling, utilities, and quarters (DUQ) platform
- process, gas compression, water injection and utilities (PCWU) platform
Production export off the complex is via two 30 inch oil pipeline tie-ins and a single 28 inch gas pipeline tie-in into pre-installed pipeline junctions located on the Azeri field subsea export pipelines to the onshore Sangachal Terminal . In addition, uniquely for the ACG project, three subsea water injection wells have been installed in the DWG development. Production from DWG is boosted by remarkable Caspian first – subsea water injection intended to ramp-up oil production by injecting seawater into DWG reservoir to increase its pressure
DWG DUQ facilities include:
- 48 slot DUQ platform
- 30-inch oil pipeline from D9WG to Sangachal terminal
- 28-inch gas pipeline from DWG to Sangachal tertminal
PCWU facilities include:
- 13 subsea water injection wells
- R1 30-inch Oil Export Riser
- R2 30-inch Oil Export Riser
- R3 28-inch Gas Export Riser
- R4 24-inch Spare Riser
- R5 12-inch Water Injection Riser
- R6 12-inch Water Injection Riser
- R7 12-inch Future Water Injection Riser
Total DWG production for the first three quarters of 2025 was on average about 52.000 barrels per day.
ACG participating interests
30.37%
31.65%
9.57%
9.31%
6.79%
5.73%
3.65%
2.92%
