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 legacy hydrocarbon accounting system had grown old alongside the business. Making changes was slow and difficult. When an upgrade became necessary, the costs were prohibitive. Santos faced a straightforward but uncomfortable question: pay to upgrade a system that still frustrated them, or replace it entirely.
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. 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
Santos selected the EnergySys Cloud Platform as the replacement for their legacy HCA system.
”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 platform now handles hydrocarbon accounting and production reporting for Santos’ operated assets at GLNG in Queensland and the Cooper Basin. Their non-operated assets in Darwin and Western Australia are also processed on EnergySys.
All operated assets were delivered in under ten months. That included 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 greenhouse gas management and reporting, commercial operations, and recent acquisitions in Western Australia. Every new requirement has gone onto the same system that their 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 SaaS 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 its Gladstone LNG asset, Elite Energy configured VesselVista on EnergySys.
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 up-to-date with industry standards.
A two-person team designed, configured, and tested the solution in nine months. Because EnergySys is PaaS, 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 legacy HCA system replaced in under ten months, at comparable cost to an upgrade, including migration of over 50 years of historic well data.
- Hydrocarbon accounting and production reporting running across operated assets in Queensland, the Cooper Basin, and non-operated assets in Darwin and Western Australia.
- GLNG’s legacy system, local servers, and Excel models replaced with a single SaaS 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 by a two-person team in nine months, with no IT architecture changes.
- Every new requirement, greenhouse gas management, commercial operations, WA acquisitions, marine vetting, added to the same platform the team already owns.
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 consultants required for most of it. No new vendor relationships to manage.
When the platform aligns with how the business thinks, it tends to spread.
