From legacy replacement to enterprise platform: how Santos keeps finding new uses for EnergySys
Santos didn’t set out to build an enterprise-wide platform on EnergySys. They set out to replace one difficult, expensive system. What happened next is the real story.
From a single hydrocarbon accounting implementation in Queensland, EnergySys now runs across Santos’ operated assets, its GLNG joint venture, and its maritime operations. Three different problems, one platform, and a team that keeps finding new places to take it.
Challenge: a legacy system that had become a liability
Santos is one of Australia’s largest upstream producers. Their operated assets span the GLNG gas project in Queensland’s Surat and Bowen Basins, and the Cooper Basin, one of the most significant natural gas and ethane processing and transportation networks on Australia’s east coast. Some of their wells have been producing for over 50 years.
Their existing hydrocarbon accounting system had been a significant investment since 2007. But by 2018, it was showing its age. Making changes was slow and difficult. When an upgrade became necessary, the costs were prohibitive. Santos faced a straightforward but uncomfortable question: continue investing in a system that still frustrated them, or replace it entirely.
The scale of what a replacement needed to handle was considerable. Santos operates a wide variety of asset types: conventional and non-conventional reservoirs; upstream and midstream assets; oil, gas, and condensate; onshore and offshore; with over 1,000 wells and numerous joint venture arrangements. Each with its own commercial agreements, some of the most complex in the industry.
At the same time, GLNG, the joint venture Santos operates upstream alongside Petronas, TotalEnergies, and KOGAS, was managing gas nominations, allocations, planning, trading, and LNG lifting data across a tangle of peripheral applications, local servers, and Excel models. It worked, after a fashion, but it wasn’t sustainable.
And at their Gladstone LNG asset, Santos needed a vessel vetting process that could keep pace with international regulations, integrate data from multiple external sources, and give port and vessel operators clear visibility of compliance and risk.
Three challenges. Three teams. All pointing at the same underlying problem: systems that couldn’t keep up with the complexity of the operation.
Solution: one platform, three implementations, built by the people who know the work
Operated assets: replacing the legacy system
In 2018, Santos made a corporate-wide decision to replace their existing hydrocarbon accounting system with EnergySys, working with reseller partner Elite Energy on the implementation.
”After a long period of evaluation, we selected EnergySys as the right tool for Santos. We were finding it increasingly difficult to make changes quickly and easily with our old system, and we were faced with prohibitive upgrade costs. We were able to deliver a modern solution built on the EnergySys Cloud for a comparable cost to an upgrade of our old system.
Project Manager for Santos and Lead Systems Improvement Engineer
The new system was configured to handle the full commercial and operational complexity of Santos’ portfolio. Over 20 commercial agreements were reviewed and accurately configured into the platform, including crude oil sales and purchase agreements, transportation agreements, and gas sales agreements. The platform integrates directly with Santos’ data historians, pulling meter data from wells, pipelines, and facilities into the allocation engine. A FIFO liquid allocation process tracks ownership of liquid products from wells through to the tank farm and on-board export tankers. Production, loss management, and budget and forecast reports were built alongside the Santos team using Power BI.
All operated assets were delivered in under ten months, including the complete replacement of the legacy system and the migration of over 50 years of historic well data going back to the 1960s.
Since go-live, Santos has expanded the platform into a full production management framework covering forecasting and loss management, greenhouse gas management and reporting, commercial operations, and recent acquisitions in Western Australia. Every new requirement has been added to the same system that the team already knows.
GLNG: replacing Excel models and local servers with a single PaaS solution
With the operated assets running on EnergySys, GLNG OPL made the same call. Having already used the platform on a smaller project, the decision to replace their legacy system was straightforward.
”EnergySys is a modern, cloud-native, low-code application with unlimited direct-to-vendor support and regular updates. It should future-proof the business. It gives us great flexibility and has delivered efficiencies. We are constantly finding areas that benefit from being moved onto the platform.
Senior LNG Supply Chain Architect, GLNG
GLNG replaced its legacy system, the peripheral applications, local servers, and Excel models it depended on, with a single PaaS solution. The entire implementation was delivered in-house, with no consultants. That saved the business significantly.
The platform now covers gas nominations, allocations, planning, trading, and LNG lifting data. GLNG has since expanded into LNG marketing, gas marketing and optimisation, regulatory compliance, and scheduled report generation.
Marine vetting: a new problem, the same platform
When Santos needed a vessel-vetting solution for their Gladstone LNG asset, they configured VesselVista on EnergySys with the reseller partner Elite Energy.
The solution evaluates vessels across safety protocols, operational history, compliance with international and local regulations, and environmental impact. It integrates with the Oil Companies International Marine Forum (OCIMF) to keep compliance data current with industry standards.
The solution was designed, configured, and tested in nine months. Because EnergySys is fully cloud-based, no changes to Santos’ IT architecture were required.
Port and vessel operators now have clear visibility of compliance and risk, and Santos has a vetting process that keeps pace with regulatory requirements without demanding ongoing specialist resources.
Outcomes: a platform that keeps growing with the business
Across Santos and GLNG, EnergySys has grown from a single legacy replacement into the operational backbone of a major Australian upstream producer.
- A corporate-wide decision in 2018 to replace a legacy system that had been in place since 2007, delivered in under ten months at comparable cost to an upgrade, including migration of over 50 years of historic well data.
- Over 1,000 wells across conventional and non-conventional reservoirs; upstream and midstream assets; oil, gas, and condensate; onshore and offshore, all running on a single platform.
- Over 20 complex commercial agreements, including crude oil sales and purchase, transportation, and gas sales agreements, reviewed, revalidated, and configured into the platform.
- Full data historian integration, FIFO liquid allocation, and Power BI reporting built alongside the Santos team.
- Scope expanded into a full production management framework covering forecasting, loss management, greenhouse gas management, commercial operations, and WA acquisitions.
- GLNG’s legacy system, local servers, and Excel models replaced with a single PaaS solution, implemented entirely in-house with no consultants.
- GLNG expanded from core gas operations into LNG marketing, gas marketing and optimisation, regulatory compliance, and scheduled reporting.
- A fully integrated marine vetting solution delivered in nine months, with no IT architecture changes.
The bottom line.
Santos started with one problem. They solved it, then found the platform was good for the next one too.
That pattern, a new challenge, the same system, a team that configures it themselves, has repeated across hydrocarbon accounting, LNG operations, gas marketing, regulatory compliance, and maritime vetting. No new vendor relationships to manage.
When the platform fits the way the business thinks, it tends to spread.
