In their simplest form, transmission pipelines are about moving molecules of gas from production facilities to various destinations. Tonnes of steel, valves, regulators, compressors, heaters and some quite sophisticated telemetry are required to achieve this. But how do we determine which molecule belongs to whom?

Already, complex contracts detail how pipeline operators are supposed to make these determinations. However, as the commercial environment becomes more competitive, this complexity is likely to increase. It is no longer practical to manage these contracts manually on a daily basis and there is a trend towards hourly management.

Automating the management of gas transportation contracts is an essential part of the industry today and this automation must comprise a variety of processes and concepts, each integral to the efficient running of commercial systems.

Data capture

A variety of processes occur on an hourly, daily, weekly or monthly basis, which need to be captured and automated. These include nomination processes, pipeline scheduling, supervisory control and data acquisition (SCADA), data capture, data validation, reporting and invoicing. Each of these is critical in its own right, but each is also dependent on the successful completion of prior steps before it can be performed. Thus automation of these tasks will provide significant benefits, and remove the errors that are introduced when moving data manually.

Operating a pipeline from a commercial perspective has a number of sub-tasks that a pipeline operator needs to perform. Tasks that need to be managed via a graphical user interface include:

• Setting of pipeline capacities
• Scheduling pipeline flows
• Controlling the flow
• Monitoring the data
• Metering, which allows reporting and invoicing tasks to be performed.

These tasks are typically much more involved than those required of external users, and as such will have a more complex feature set.

Maintaining data input integrity

External inputs come from the shippers as customers, and from the SCADA system which provides meter data.

Human input data is susceptible to key stroke errors, whereas the meter data can be transferred automatically from the field via the SCADA system, minimising the possibility of error and maintaining data integrity.

Internal data can be both static and dynamic. Using the SEA Gas pipeline contract management system, contract information can be pre-programmed to apply when particular conditions occur, but may require lengthy embedded calculations that retrieve data from a variety of sources. This way, pipeline controllers can have access to dynamic data relating to the state of the pipeline, such as line pack and equipment availability. These variables get updated on a daily basis and impact on the services the pipeline can provide.

System output and configuration

Pipeline contract management systems also need to provide a variety of output, including invoices, reports, and notifications. Once produced, both invoicing and reports will be delivered electronically via email or post, at the end of a gas day or billing month. On a more immediate basis, pipeline operators can be notified of system events, outages or errors that occur in the system, by email or SMS.

When configuring the system, the subtleties surrounding the different business rules that apply to the services offered need to be carefully understood and integrated. For instance, once firm services have been utilised, the available interruptible capacity needs to be determined and then incorporated. The contractual fine print may reveal different conditions that apply when an intra-day change occurs, and this needs to be understood carefully.

Data presentation

Bringing all of these concepts together can be done in a variety of ways, and indeed multiple solutions may be required. Data may need to be presented in both tables and graphs, some of the data may be edited and some not, some users may be allowed to access a particular data set but others not and, as already identified, the data will need to be sent via SMS, email and regular post. Limiting options at any step will restrict the usability of the system.

Technology and security

Finally, the technology and security aspects of the systems need to be considered. Appropriate consideration of the size of the system (data points, users etc), security requirements (https, VPN, encryption) and database preference (Oracle, MSSQL) will direct choices made in these areas. A review of potential points of failure should also be conducted to ensure appropriate redundancy is incorporated. Naturally, cost benefit analysis will also drive the direction the application should take.

This article is a summary of Jamie Coombs’ paper, 'Automating the Management of a Gas Pipeline System', which he presented at the 2009 Australian Pipeline Industry Association Convention. Mr Coombs is a Commercial Analyst with SEA Gas.