Plateau Production Rates confirmed at Viura Field

Prospex Energy plc / Index: AIM / Epic: PXEN / Sector: Oil and Gas

24 October 2025

Prospex Energy plc

("Prospex" or the "Company")

Plateau Production Rates confirmed at the Viura Field

Prospex Energy plc (AIM: PXEN), the AIM quoted investing company focused on European gas and power projects, is very pleased to confirm that gas production from the Viura‑1B well in the Viura gas field in northern Spain has reached the planned plateau rate of 180,000 normal cubic metres per day. The operator of the Viura field, HEYCO Energía Iberia S.L. ("HEI" or the "Operator") brought the well back into production on Friday 17 October 2025.

The reported flow rate of gas on 22 October 2025 from the Viura-1B well was 186,333 normal cubic metres, which is equivalent to 196,490 standard cubic metres or 6.9 million standard cubic feet. This rate was achieved at a 30% choke setting. This will be the ongoing plateau production rate. The water cut continues to be low and is reducing. 

Prospex owns 7.24% of the Viura field through its ownership of 7.5% of HEI. Prospex is accruing 14.47% of the production income from the Viura gas field until payback of its initial capital investment (expected to be ≈£8 million) plus the accrued 10% p.a. interest thereon.

Mark Routh, Prospex's CEO, commented:

"I am very pleased to confirm that the flow rate of natural gas from the Viura-1B well in the Viura field has achieved the planned plateau production rate within a week of the recommencement of production last Friday.  The confirmation of the performance of this reservoir is especially pleasing after the recent frustrating one-off event which delayed the resumption of production after the successful workover in July.

"This confirms our view that Viura is a prolific gas field and was an excellent addition to our portfolio and that it is likely to continue production and cash flows long into the future."

Background

The Viura acquisition significantly increased Prospex's estimated reserves by 6.5 Bcf (0.18 Bcm) net to Prospex. The Operator's best estimate of recoverable gross remaining reserves at the Viura field is 90 Bcf (2.5 Bcm) and is expected to increase upon further evaluation of the newly drilled horizons.  Once the newly reprocessed 3D seismic is reinterpreted it is the Operator's intention to update the reservoir model, gas in place and the reserves for the Viura field.

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulation (EU) No. 596/2014 as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018, as amended by virtue of the Market Abuse (Amendment) (EU Exit) Regulations 2019.

* * ENDS * *

For further information visit www.prospex.energy or contact the following:

Notes

Prospex Energy PLC is an AIM quoted investment company focussed on high impact onshore and shallow offshore European opportunities with short timelines to production. The Company's strategy is to acquire undervalued projects with multiple, tangible value trigger points that can be realised within 12 months of acquisition and then applying low-cost re-evaluation techniques to identify and de-risk prospects. The Company will rapidly scale up gas production in the short term to generate internal revenues that can then be deployed to develop the asset base and increase production further.