the alder field

alder crew at work

In November 2016, nearly 40 years after its discovery, Chevron and Alder co-venturer ConocoPhillips (U.K.) Limited produced first gas from the Alder field. In 2018 Alder's daily production averaged 4,094 barrels of gas condensate and 57.98 million standard cubic feet of natural gas.

a new stream of production

The Alder field brings a new stream of natural gas to Chevron’s production portfolio and the U.K. Yet this North Sea asset is no newcomer to the country’s energy scene.

Discovered in 1975 in Block 15/29a, Alder is a high-pressure, high-temperature (HPHT) gas condensate field, approximately 17 miles (28 km) to the west of the Britannia field. When discovered, the U.K. oil and gas industry was still in its infancy and focused on developing “elephant” discoveries. It wasn’t until 2009, that advances in subsea innovation and technology, and the availability of throughput at the host platform, Britannia, made Alder possible.

alder - journey to first gas

alder - journey to first gas

Follow Chevron's U.K. Alder field on its journey from discovery to first production and learn how technology has unlocked its potential.

maximising recovery of U.K. resources

The most cost effective development solution for Alder, located 100 miles (160 km) east of Scotland in the Central North Sea, was to tie the field back to Britannia, in which Chevron holds a 32.38 percent non-operated working interest, via an advanced 17-mile (28 km) subsea pipeline.

To successfully receive and process the gas, Britannia required significant modification including the installation of a new processing module, which was safely and successfully installed in July 2015. Weight was limited, so lighter, specialty steels had to be used to build the new 850 metric tonne module. The "brownfield" scope for the existing platform was as challenging as the module design itself, involving extensive offshore work on a producing platform.

Throughout 2016, Chevron achieved a number of milestones as the Alder development moved towards first production. These included drilling the Alder reservoir section to total depth and safely and successfully installing the tubing head spool, the subsea protection covers, the subsea isolation valve and the manifold.

Alder produced gas condensate (a mixture of hydrocarbon liquids from natural gas) is processed at new dedicated facilities on the Britannia platform. Condensate and gas is then exported to Scotland-based terminals at Grangemouth and the Scottish Area Gas Evacuation, St Fergus, respectively.

applying technology and innovation

The development of Alder has been enabled through the application of innovative subsea technologies designed to meet the temperature and pressure challenges of the field.

Key technologies have included a number of firsts for Chevron in the North Sea, including a vertical mono-bore subsea tree system; a subsea high integrity pressure protection system (HIPPS); and a specially designed corrosion monitoring system to measure the real-time condition of the 17-mile production pipeline.

fly-through alder technologies

fly-through alder technologies

Learn about the innovative technologies Chevron is using at Alder field in the North Sea in this fly-through animation that takes you from reservoir to platform.

leveraging U.K. capability and expertise

A showcase for the U.K.'s world-leading subsea manufacturing and engineering skills, Chevron placed more than 70 percent of the development work for Alder, with contracts worth more than £440 million, with U.K. companies. Work was undertaken at a number of U.K. locations, including Aberdeen, Invergordon, Leeds and Newcastle.

The safe and successful completion of the Alder development was underpinned by strong collaboration between Chevron, from the Alder project team to subject matter experts from across Chevron's Energy Technology Company and Global Technology Centre in Aberdeen and ConocoPhillips, operator of the Britannia field and co-venturer in the Alder field.

The Alder field is operated by Chevron North Sea Limited (73.7 percent); ConocoPhillips (U.K.) Limited holds a 26.3 percent non-operated working interest in the field.