Svein Alsaker, governor of Norway's Hordaland county, is due to inaugurate the Vestprosess facilities at Mongstad today, 7 December.
This extension to Statoil's oil refining complex near Bergen began operating on 1 October.
In addition to a new unit for processing natural gas liquids, the development embraces a pipeline from Norsk Hydro's Sture oil terminal and the Statoil gas treatment plant at Kollsnes.
Two new rock cavern stores and an additional jetty have also been constructed at Mongstad as part of Vestprosess.
Establishing a link between Mongstad and the nearby facilities at Sture and Kollsnes gives the refinery access to more feedstock, says Leidulf Ramstad, vice president for refining in Statoil.
The Vestprosess pipeline delivers condensate and NGLs (propane and butane) to Mongstad. These light petroleum fractions from Sture/Kollsnes were either sold together with crude oil at a lower price than they could fetch separately, or injected back into the reservoir.
Together with North Sea crude from the newly-laid Troll Oil Pipeline II, this flow helps to boost annual output at the refinery by 25 per cent to 10 million tonnes of petrol and diesel oil.
The refinery has also expanded its annual production of propane and butane to 500,000 tonnes.
Mr Ramstad reports that these increases have been achieved without using more energy, because the NGL processing plant utilises waste heat from the rest of the Mongstad facility.