The Neptun Deep Block is located in the Romanian Black Sea, approximately 160km from the shore. (Credit: © OMV Aktiengesellschaft)
Saipem secured a €1.6bn contract to provide EPCIC services for the offshore facilities of the project. (Credit: SAIPEM SpA)
Neptun Deep gas field is expected to hold recoverable volumes of around 100 bcm of gas. (Credit: tom Jervis/ Flickr/ Wikipedia)

The Neptun Deep is the largest natural gas project in the Romanian Black Sea being developed by OMV Petrom and Romgaz.

The two companies took the final investment decision (FID) to develop the Domino and Pelican South natural gas fields in the Neptun Deep block project in June 2023. The development of the offshore project will entail an investment of up to €4bn.

Drilling activities at Neptun Deep are planned to commence in 2024, with first gas expected to be achieved in 2027.

The project will produce around 8 billion cubic metres (bcm) of natural gas annually at plateau (~140,000 boe/d) for nearly ten years.

Location details

The Neptun Deep project is located within the Neptun Deep block in the Black Sea. The block includes an area of ​​7,500km2 situated around 160km from the shore.

The water depth in the region ranges between 100m and 1,000m.

Neptun Deep contains recoverable resources of around 100bcm of natural gas. The natural gas found at the Neptun Block is of very high purity dry, biogenic gas comprising 99.5% methane, thereby reducing processing requirements.

Neptun Deep Gas Field Background Details

In November 2008, OMV Petrom and ExxonMobil formed a joint venture (JV) for the deepwater sector of the Neptun Block.

Since 2008, two 3D acquisition campaigns, two exploration drilling campaigns and two exploration drilling programmes were conducted in the block.

More than €1.5bn was invested to conduct the exploration and appraisal activities.

The first natural gas discovery was made in 2012 by the first deepwater well, Domino-1, during the first drilling campaign.

In the second drilling campaign during 2014-2015, seven wells were drilled including Pelican South-1 that led to the discovery of the Pelican South field.

In 2019, ExxonMobil announced its plan to exit the Neptun Deep block and the company signed an agreement to sell its Romanian upstream affiliate, ExxonMobil Exploration and Production Romania, to Romgaz in May 2022 for more than $1bn.

OMV Petrom became the operator of the Neptun deep offshore project in August 2022. OMV Petrom and Romanian natural gas producer Romgaz each hold a 50% interest in the project.

The JV submitted the declaration of a commercial discovery of the Domino and Pelican Sourth reservoir to the Romanian National Agency for Mineral Resources in December 2022. It was followed by the FID in June 2023.

The Development Plan for the Domino and Pelican South fields was endorsed by Romania’s National Agency for Mineral Resources in August 2023.

Neptun Deep Gas Field Development 

The project will involve development of the Domino and Pelican South commercial natural gas fields in the Neptun Deep block.

Domino Field is located at a water depth of approximately 1,000m, while the shallower Pelican South is located at 120m water depth.

The infrastructure will include ten wells, three subsea production systems, and associated flow lines, an offshore platform, the main natural gas pipeline to Tuzla, and a natural gas measurement station.

Domino field will produce from six wells, which will be tied to two subsea production systems. The remaining four wells will be used to produce from Pelican South via one subsea production system.

The gas from the deep natural gas fields will be processed at the unmanned shallow water platform.

The subsea production systems will be connected to the platform through pipelines and flexible flowlines. The flowlines will be continuously direct electrically heated to enhance reliability and reduce operational costs.

The entire infrastructure will be remotely operated through a digital twin. The offshore platform will generate its own energy for operations.

The gas will be dried or dehydrated to sales gas specification and then sent to shore via a 160km pipeline. The processed gas will enter the national gas transmission network at Tuzla after passing through a metering station.

Contractors Involved

In March 2023, OMV Petrom and Transgaz signed a nearly €276m contract to deliver the natural gas recovered from the Neptun deep gas field to the National Transport System (NTS), via the Tuzla entry/exit NTS point.

Under the agreement, the transport contract will run for a period of 17 years from September 2026 to September 2042.

In August 2023, Saipem secured a €1.6bn contract to provide engineering, procurement, construction, installation and commissioning (EPCIC) services for the offshore facilities of the project.

The scope of work entails EPCIC of a gas processing platform at around 100m water depth, three subsea developments, a 30-inch 160km long gas pipeline and associated fibre optic cable from the shallow water platform to the Romanian coast.

Saipem will build the gas processing platform at its yards in Italy and Indonesia, while the offshore operations will be conducted by the Saipem 7000 and JSD 6000 vessels.