Development of a method for evaluation of measures used for winterization of offshore facilities and units

Abstract

The environmental conditions in the Barents Sea include low temperatures, wind, snow and precipitation influencing safety, working environment, operations and equipment functionality. The conditions are not extreme compared to other Arctic areas, however they do necessitate protection and winterization of the facility. A study performed for the Petroleum Safety Authority (PSA) in 2016 identified known measures for winterization of facilities in the Barents Sea. The study found uncertainties related to the effect the measures have on winterization when considering environmental conditions. Further work was recommended to evaluate the effect of measures when considering performance influencing factors. A new study was initiated by PSA to develop a method to evaluate the efficiency of measures and a means to document the results. The method considers how well a measure achieves a specific safety and winterization goal, effect of the measure on energy consumption, effect of the measure on investment cost and operating cost, and vulnerability of the measure, including operational and organizational factors. In order to refine and test the method, it was applied to case studies considering a year-round production facility, a light well intervention vessel and a drilling facility used in the winter season in the Barents Sea. The paper is not intended to be a research paper but is a presentation of a method that has been developed to perform an initial evaluation of the effectiveness of winterization methods.