Wood Group – Significant cost reduction with virtual metering

Submitted by Wood Group 

Impact

Long term reliability of subsea multi-phase meters is an ongoing challenge. These can incur costs of tens of millions of dollars over the life of a field, with maintenance cost reported to be greater than $100,000 per month, and replacement cost greater than $3 million per event. With the range and variety of subsea solutions there can be a number of different subsea, topside and downstream meters in play. Wood Group’s virtual metering system (VMS) makes a robust, low cost backup for physical metering, allowing greater flexibility for maintenance scheduling and frequency.

Virtual metering technology works by using proprietary modelling software to draw from available field instruments and generate online flowrate estimates. Across the whole well system VMS can reconcile flowrates to help customers understand total allocation and mitigate errors in upstream meters.

In one example the VMS was tested for an extended period when all the physical devices failed within six months of installation. After two years of operation the virtually metered flowrates matched the total from export meters with less than 0.5% error margin.