ADX Energy (ASX:ADX) is preparing for a significant operational programme in 2026, including the resumption of flow testing at its Welchau-1 well and the commencement of a multi-well gas and oil drilling campaign across its Upper Austrian assets.
The company, listed on the ASX as ADX, is progressing with planning and contracting for the Welchau-1 testing phase after a favourable ruling from the Upper Austria state administrative court confirmed previously granted environmental approvals.
Testing at Welchau-1 is scheduled to resume in January 2026. Operations will focus on three remaining reservoir intervals, beginning with fluid sampling of the Reifling formation, which was perforated before the suspension of activities earlier this year.
ADX Energy also intends to begin a three-well shallow gas drilling campaign, comprising the HOCH-1, GOLD-1 and SCHOE-1 wells. These wells are expected to contribute to a rapid increase in biogenic gas output, consisting of 99% methane, with limited operational risk. Drilling and environmental permits are anticipated to be obtained by the end of 2025, enabling well construction to commence in January 2026 and drilling to begin the following month.
In the latter half of 2026, the company plans to drill near-field oil appraisal wells near its Anshof field. The existing permanent production facility, which has a capacity of 3,000 barrels per day, is capable of accommodating additional output if new production is achieved.
Executive chairman Ian Tchacos said the company would recommence testing at Welchau-1 to assess the potential of the intersected reservoirs. He stated that three of the four reservoir intervals with oil and gas shows and recovered hydrocarbons remain untested, meaning the well’s potential has not been fully evaluated. He added that ADX may deepen the Welchau-1 well in future, subject to approvals, to explore further potential at the Welchau Deep prospect.
ADX intends to contract a workover rig and procure the necessary equipment and services for the testing programme. Prior to rig mobilisation, wellhead fluid sampling from the Reifling formation will be undertaken once adequate inflow is observed. Following this, the well will be swabbed by wireline to lower hydrostatic pressure and encourage flow. Acid stimulation is expected to be applied to the Reifling formation to improve productivity. Subsequent testing will depend on the analysis of results from both the Reifling and Steinalm formations, where condensate was recovered during earlier evaluations.
In parallel, ADX has advanced seven shallow biogenic gas prospects within its ADX-AT-I and ADX-AT-II licences to a drill-ready stage. These low-cost, low-risk prospects are located close to existing gas infrastructure and can be commercialised quickly. The upcoming programme will target the HOCH-1 and SCHOE-1 wells in the 50%-owned MND ADX-ATI Investment Area, along with the GOLD-1 well in the company’s wholly owned ADX-AT-II area. Work is continuing to mature an additional four shallow gas prospects within the expanded 100%-owned ADX-AT-I licence.
Tchacos said the shallow gas drilling programme, together with the SGB oil appraisal well near the Anshof field, provides strong potential for organic growth. He noted that the low-risk nature of the programme increases the likelihood of substantial production gains, with successful initial results likely to lead to further follow-up drilling.
Land has been secured for the SGB-1 well, which will tie into the Anshof production facility. The well will target proven Eocene sandstone reservoirs, with secondary potential in deeper Cretaceous formations. Drilling of SGB-1 is expected in the third quarter of 2026, and ADX is seeking to farm down part of its interest before drilling. The company considers the chance of success for an oil discovery at this location to be high.
