Operational Update

Empyrean Energy PLC

17 September 2026

17 September 2026

This announcement contains inside information

Empyrean Energy PLC / Index: AIM / Epic: EME / Sector: Oil & Gas

Empyrean Energy PLC (‘Empyrean’ or ‘the Company’)

Operational Update

Empyrean Energy plc (“Empyrean” or the “Company”), the oil and gas exploration and development company with interests in Austria, Indonesia, and the United States, is pleased to provide an update on progress at theDuyung PSC and the Mako Gas Field in Indonesia (“Mako Gas Project”).

Conrad Asia Energy Ltd (“Conrad’, (ASX:CRD)) and its majority-owned subsidiary, West Natuna Exploration Limited (“WNEL”), as operator of the Duyung PSC, today advised that several critical milestones have recently been completed, and the project remains on budget and on track to complete construction and begin production in the fourth quarter of 2027.

Subject to the completion of documentation, as detailed in the announcement on 10 September 2026, Empyrean is entitled to 8.5% of all cash payments to WNEL including revenue from gas sales from Mako.

These critical milestones are outlined below.

Highlights

• As reported previously, contracts had been signed earlier this year for (i) the Mobile Offshore Production Unit (“MOPU”), (ii) the drilling rig, (iii) the Conductor Support Frame (“CSF”), (iv) the Subsea Umbilical, Riser, and Flowline (“SURF”) and (v) multiple supporting facilities and services. Below are the updates on these workstreams.

1. MOPU: contract with PT Duta Marine/PT Pakarti Tirtoagung (“PT DM”) for the provision of a leased MOPU unit, with the scope of work including (i) sourcing and conversion of a donor jack-up drilling rig to a MOPU in Batam, with a raw gas design capacity of 172 mmscfd, (ii) mobilisation to site, (iii) bareboat charter until end of current PSC term (Jan 2037) plus five annual extension options, (iv) operations and maintenance of the MOPU, and (v) demobilisation back to Batam and the end of the contract life.

The donor jack-up drilling rig, Valaris 104, to be converted and used as Mako MOPU, has been successfully wet-towed through the Strait of Hormuz and loaded onto a dry-tow vessel for transport to Batam, Indonesia, for conversion. The rig is expected to reach the yard by end 3Q 26 as planned.

Key equipment for the MOPU includes the compression system. Factory Acceptance Testing (“FAT”) of the key 17Mw and 10Mw motors has been completed in Germany. Transportation of the units from Germany to Batam is slated for early 4Q 26. The compressor FAT is set for mid-Q4 26 in San Diego, with shipment expected to commence in the same quarter.

Fabrication by PT DM is expected to commence before the end of September 2026 at the PaxOcean Yard, Batam, with an official ceremony planned for later in the quarter.

The contract remains on track.

1. Drilling Rig: contract with PT Pertamina Drilling Services Indonesia, through the PDSI – ADES Consortium, for a firm period of 180 days, with options to extend, for the provision of an independent-leg cantilever jack-up drilling rig, the Admarine 502, for the drilling of six development wells and the installation of the CSF to support the development of the Mako Gas Field. A sharing arrangement for the rig has been agreed with another operator, allowing the sharing of mobilisation/demobilisation costs between the parties.
2. CSF: contract with PT PAL Indonesia (“PT PAL”) with scope of work including (i) detailed engineering, (ii) procurement, (iii) construction and assembly of the jacket and topside structures, and (iv) transportation.

Engineering and procurement are ongoing, with some steel shipments already on site and others in transit. The first cut of a beam fabrication commenced on 14 September 26.

1. SURF: contract with PT Timas Suplindo (“Timas”) with scope of work including (i) verification of front-end engineering and design and execution of a detailed engineering design, (ii) procurement, management, storage, and integration of materials, (iii) construction and assembly, coating and inspection of subsea structures and associated SURF components, (iv) transportation and installation, and (v) pre-commissioning and commissioning support.

Engineering and procurement are ongoing, and significant work has been completed to optimise the offshore sequence in conjunction with drilling activities to minimise simultaneous operations. Site fabrication will commence mid-4Q 26. The contract remains on track.

• WNEL has signed contracts and/or issued letters of award/variation orders covering 90% of project capital contracts. Total project cost remains at US$320 million for the Mako gas project. In addition, the MOPU contract requires payment of US$4 million for the purchase of a donor rig and a US$26 million facility equipment down payment, which is accounted for as part of a previously announced provision of approximately US$35 million (100%).
• As reported previously, PT PLN Energi Primer Indonesia (“PLN EPI”), the contracted buyer of 100% of the gas from the Mako Gas Project, completed the "hot tap" connection on the West Natuna Transportation System (“WNTS”) to the Pemping gas pipeline project, which is the delivery point for Mako’s gas into Batam. This marked an important step in developing infrastructure that will connect the West Natuna Basin to Batam. Commissioning is scheduled to take place once the Onshore Receiving Facility is deemed ready and gas is available for commissioning purposes. Based on the current plan, commissioning is projected for during September / October 2026 (well in advance of any gas supply from Mako).

• Data centre-driven power demand in Batam is booming, with Conrad now evaluating opportunities within its portfolio to increase gas supply to the area.

Empyrean CEO, Gaz Bisht, commented:

“We are very pleased with the continued progress at Mako, with a number of important development milestones now achieved and the major project workstreams progressing in line with plan. The project remains on budget and on track for first gas in the fourth quarter of 2027.

Mako is also strategically well positioned. The project will supply gas into Batam, which is emerging as an important regional data centre and industrial hub within the Singapore–Johor–Riau economic corridor. The rapid growth in power demand across the region is creating increasing demand for reliable gas-fired power generation and reinforces the importance of Mako’s future gas supply.

With the major contracts now substantially committed and construction activities progressing across the MOPU, drilling, CSF and SURF workstreams, we look forward to further milestones as the project advances towards production.

For Empyrean, Mako provides a significant long-term exposure to gas production and cash flow, while our recently announced entry into Austria provides an additional near-term development opportunity as we continue to build a broader portfolio of gas assets.”

For further information please visitwww.empyreanenergy.comor contact the following:

Empyrean Energy plc	Tel: +61 (8) 6146 5325
Gaz Bisht
Cavendish Capital Markets Limited (Nominated Advisor and Broker)	Tel: +44 (0) 207 220 0500
Neil McDonald Pearl Kellie
AlbR Capital Limited (Joint Broker)	Tel: +44 (0)20 7469 0930
Colin Rowbury

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