The Medgaz pipeline is the first deepwater pipeline in the Mediterranean Sea to transport natural gas from Algeria to Spain.

Operational since April 2011, the 210km-long and 24in-diameter subsea pipeline is currently capable of transporting up to 8 billion cubic metres (bcm) a year.

The construction of the £890m ($1.4bn) pipeline was completed in December 2008, while pre-commissioning works were concluded in March 2009. The pipeline was connected to the Spanish gas network at the Almeria terminus in March 2011.

Algeria’s state-owned oil and gas major Sonatrach holds a 51% stake in the pipeline, while the remaining 49% stake is held by Spain-based Naturgy Energy Group (formerly Gas Natural Fenosa).

The Medgaz developers sanctioned an expansion project to increase the capacity of the pipeline by 25% to 10bcm a year in 2019.

Scheduled for commissioning in 2021, the expansion project involves a fourth compressor train at the Beni Saf compressor station with an estimated investment of £59m ($75m).

Medgaz pipeline route and design details

The Medgaz pipeline is a natural gas pipeline in the Alboran Sea, a part of the Mediterranean Sea. The pipeline receives natural gas supply from the Hassi R’Mel fields in central Algeria.

The 210km-long subsea pipeline originates from the Beni Saf compressor station in Algeria’s north coast and terminates at a receiving terminal in Almeria, on the south coast of Spain.

The Beni Saf compressor station consists of three turbo-compressors, three gas turbines, and the related equipment. A fourth compressor train will be added as part of the pipeline expansion project.

The water depth along the route of the pipeline is up to 2,160m. The J-lay and S-lay methods of pipeline construction were used in the deepwater and the shallow water sections respectively.

Each 24in-diameter pipe joint used for the pipeline is 12m-long and is made of carbon steel with multiple layers of coating.

Project finance and development partners

The European Investment Bank provided a loan of £428m ($684m) for the Medgaz pipeline project in November 2010.

The pipeline was previously owned by Sonatrach (42.96%), Abu Dhabi-based sovereign fund Mubadala (42.09%), and Naturgy (14.95%). Mubadala decided to sell its stake in the pipeline in October 2019. Naturgy acquired a 34.05% stake for approximately £394m ($488m) in April 2020 while Sonatrach picked up the remaining 8.04% stake in May 2020.

Contractors involved

Arkad (formerly Arkad-ABB) bagged an engineering, procurement, and construction (EPC) contract worth £39m ($50m) for the expansion of the Beni Saf compression station in November 2019. The contract involves the installation of the fourth turbo-compressor train and related equipment. Dresser-Rand was selected to supply the fourth turbo-compressor.

Mitsui and Sumitomo were awarded the contract to manufacture and supply pipes for the Medgaz project in 2007.

Saipem was responsible for subsea pipeline engineering, construction, and pre-commissioning. The pipelay vessels Saipem 7000, Castoro Sei, and Crawler were deployed for constructing the pipeline in 2008.

Saipem 7000 laid pipeline in the deepwater section while Castoro Sei laid pipeline in the shallow water section.

A joint venture of Tecnicas Reunidas and Amec Spie was awarded a contract to build the compressor station in Beni Saf and the receiver terminal in Almeria.

Rolls Royce was contracted to supply and install three gas compressor packages for the compressor station in Beni Saf in February 2007. The contract scope included three Dresser-Rand Datum compressors and three RB211 gas turbine packages.