SAGE Terminal System Implementation with CHARM

The SAGE (Scottish Area Gas Evacuation) Terminal, operated by SAGE North Sea Limited, a wholly owned subsidiary of Ancala Midstream, transports and processes gas from fields in the Northern and Central North Sea and Norwegian Continental Shelf. Gas is redelivered into the NTS at St Fergus and NGLs are redelivered to Shippers into the FPS and SEGAL systems.

In 2019, Ancala engaged Accord to replace an ageing IT system which performed the nomination, allocation, attribution and reporting functions. Ancala selected the EnergySys platform for the implementation of STAR (SAGE Terminal Allocation and Reporting).

The scope of STAR includes: modelling of the physical and commercial arrangements, capacity management, stock and substitution arrangements, nominations and scheduling, calculation of allocated and attributed quantities, mismeasurement handling and reallocations, reporting to third party operators and Shippers. Management and approval of deviations and dispensations is also built into the application. STAR also calculates all emissions quantities and uncertainties and prepares the annual verification reports for submission to the auditor.

The existing system was difficult to extend when new fields came on stream or revised contract arrangements were required. STAR allows authorised personnel to add to the physical and commercial configuration and, where required, extend the commercial rules. 

The full audit trail of modifications and applicable date ranges maintain the effective network allowing calculations to be rerun historically.

The existing system issued over 100 reports each day.  Ancala required a solution which consolidated these reports and allowed external parties to access published reports directly.  EnergySys permitted direct data publication through an ODATA connection.  

Authorised third parties can download their data into Excel or directly into their own systems.

The SAGE system is characterised by complex allocation agreement rules.  Ancala required a system which could implement specific rules within a standard framework and which would provide transparent auditing of the steps taken throughout the allocation.  The allocation agreements were implemented by Accord within EnergySys using standard Excel templates.  

In STAR, the allocation calculations are linked to agreement clauses and every run of the allocation produces Excel audit logs showing all input and output data as well as every calculation step referenced to the relevant clauses.  These are automatically issued to third parties once the allocation has been approved.

At the heart of the SAGE Allocation is a requirement to run a process model of the SAGE Plant. CHARM is a cloud-based process simulation package developed by Accord which provides the calculations required for hydrocarbon allocation. 

CHARM can be directly called from EnergySys and has been integrated into the STAR system providing process simulations based on the daily operation of the plant and the feed compositions from offshore.

Following the implementation of the core system, Accord developed a data visualisation tool by connecting PowerBI directly to STAR. This provides the management team with a real-time view of a wide range of KPIs – e.g. forecast and actual revenue, production and capacity, emissions, outages. 

The tool allows users to query and represent their critical business data in the ways most useful to them. This drives real insights across the business and has proved extremely powerful in overall management and monitoring of the terminal performance. 

With STAR as the hub of all production and revenue data, extending the visualisation is straightforward and can be performed by STAR business users.