Development

Alvheim is a field in the central part of the North Sea, ten kilometres west of the Heimdal field and near the border to the UK sector. The field includes the six discoveries 24/6-2 (Kameleon), 24/6-4 (Boa), 25/4-7 (Kneler), 25/4-10 S (Viper), 25/7-5 (Kobra) and 25/4-3 (Gekko). Boa lies partly in the UK sector. The water depth is 120-130 metres. Alvheim was discovered in 1998, and the plan for development and operation (PDO) was approved in 2004. The field is developed with subsea wells tied to a production, storage and offloading vessel, Alvheim FPSO. Production started in 2008. The Vilje, Volund and Bøyla fields are tied-back to Alvheim. The Skogul discovery has been tied-back to the Alvheim FPSO via the Vilje field.

Reservoir

Alvheim produces oil and gas from Paleocene sandstone in the Hermod and Heimdal Formations. The reservoirs are in submarine fan deposits and lie mostly at depths of 2,100 to 2,200 metres. The reservoir quality is good.

Recovery

The field is produced by natural water drive from an underlying aquifer.

Transport

The oil is stabilised and stored on the Alvheim FPSO before it is exported by tankers. Processed rich gas is transported by pipeline from Alvheim to the Scottish Area Gas Evacuation (SAGE) pipeline on the UK continental shelf.

Status

Due to greater in-place volumes and longer infill wells, Alvheim has seen a significant increase in the estimated recoverable volumes of oil and gas since the PDO. The capacity of the Alvheim gas compressor is limited due to further development of the Boa deposit. Measures including reducing gas lift and choking back or shutting in of wells were taken to maximise the overall production. Alvheim production has been better than anticipated. Alvheim is a potential hub for more discoveries in the area, for example 25/4-2 (Trine) and 25/5-9 (Trell).