Highlights

  • D3 Energy reported an independently certified maiden Prospective Resource for the Hydrohelix and Cootanoorina prospects within its wholly owned PEL121 permit.
  • The two prospects contain a combined net 2U Prospective Resource of 54 billion cubic feet of recoverable helium.
  • The certified estimate also includes 88 billion cubic feet of recoverable hydrogen and 226 billion cubic feet of methane on a net 2U basis.
  • The resource was assessed across the Heavitree Sandstone and Fractured Basement reservoir settings.
  • PEL121 and the adjoining PEL122 cover a combined 5,865 square kilometres in South Australia’s Arckaringa Basin
  • D3 Energy has commenced a farm-out process for the Hydrohelix prospect to support future drilling activity.

D3 Energy Limited (ASX:D3E) has established a second geographically diversified Prospective Resource base after receiving independent certification for helium, hydrogen and methane volumes at the Hydrohelix and Cootanoorina prospects in South Australia. The two prospects are located within the company’s wholly owned PEL121 exploration permit in the Arckaringa Basin, with the estimate completed by independent reserves and resources auditor Sproule ERCE.

D3 Energy shares were trading at AUD 0.38 during the morning session on 15 July 2026, down 1.30%, or AUD 0.005. Despite the morning movement, the stock remains up 65.22%, or AUD 0.15, over the past year.

The company is focused on helium, hydrogen and methane opportunities across South Africa and Australia. Its South Australian portfolio comprises PEL121 and the adjoining PEL122, which together cover approximately 5,865 square kilometres in the Arckaringa Basin. The permits are situated near the Olympic Dam uranium deposit and contain geological features considered relevant to the generation, migration, accumulation and trapping of naturally occurring critical gases.

Maiden Resource Establishes Australian Critical Gas Base

The independently certified estimate covers the Hydrohelix and Cootanoorina prospects and includes volumes modelled within both the Heavitree Sandstone and Fractured Basement.

On a net 2U basis, the two prospects contain an estimated 54 billion cubic feet of recoverable helium, 88 billion cubic feet of recoverable hydrogen and 226 billion cubic feet of recoverable methane.

The lower 1U estimate includes 14 billion cubic feet of helium, 21 billion cubic feet of hydrogen and 58 billion cubic feet of methane.

At the upper 3U level, the estimate rises to 190 billion cubic feet of helium, 331 billion cubic feet of hydrogen and 803 billion cubic feet of methane.

The Prospective Resource is unrisked and relates to accumulations that have not yet been discovered through drilling. D3 Energy noted that the estimates carry both discovery and development risks. Further exploration, appraisal and evaluation will therefore be required to establish whether commercially recoverable quantities of helium, hydrogen or methane are present.

The certification does not represent reserves or confirmed discovered resources. Instead, it provides an independently assessed estimate of the quantities that may potentially be recovered if exploration leads to a discovery and a future development project proceeds.

Hydrohelix and Cootanoorina Advance from Seismic Interpretation

D3 Energy has so far identified two prospects and nine additional leads within PEL121 using available seismic data.

Hydrohelix is the larger of the named prospects, covering approximately 148 square kilometres. Both Hydrohelix and Cootanoorina were matured using seismic interpretation that mapped the structural and geological features considered important to the regional helium and hydrogen system.

The company’s interpretation centres on deep basement faulting, the Heavitree Sandstone reservoir, fractured basement units and a regional evaporite seal.

Deep basement faults are considered potential pathways for gases generated at depth to migrate into suitable reservoir units. The Heavitree Sandstone and fractured basement provide possible storage intervals, while the regional evaporite sequence may act as a seal capable of retaining accumulated gases.

The maiden resource certification supports D3 Energy’s interpretation that these geological components extend across PEL121 and may form part of a functioning regional gas system.

The company plans to continue assessing the nine remaining leads across PEL121, while further work is also expected across the adjoining PEL122 permit. The objective will be to determine whether additional leads can be matured into defined prospects and potentially incorporated into future resource assessments.

Resource Estimates Span Three Gas Types

The latest certification gives D3 Energy prospective exposure to three gases within the same exploration setting.

Helium is estimated at 14 billion cubic feet on a 1U basis, 54 billion cubic feet at 2U and 190 billion cubic feet at 3U.

Hydrogen volumes are estimated at 21 billion cubic feet under the 1U case, 88 billion cubic feet under the 2U case and 331 billion cubic feet under the 3U case.

Methane accounts for the largest estimated volume, with 58 billion cubic feet at 1U, 226 billion cubic feet at 2U and 803 billion cubic feet under the 3U estimate.

The range between the 1U, 2U and 3U cases reflects uncertainty in the current geological interpretation and the absence of exploration drilling at the prospects. The 1U estimate represents a lower-case scenario, 2U provides the best-case estimate, and 3U reflects an upper-case scenario based on the available subsurface information.

Further seismic interpretation and drilling will be needed to narrow these ranges and determine whether the prospective accumulations exist.

Mt Kitty-1 Provides Regional Geological Comparison

D3 Energy considers the geological setting across PEL121 and PEL122 to be comparable to the nearby Mt Kitty-1 well.

According to the company, Mt Kitty-1 recorded helium concentrations of up to 9%, hydrogen concentrations of up to 11.5% and methane concentrations of up to 13%.

The comparison is based on the presence of deep basement faulting, the Heavitree Sandstone, fractured basement reservoir potential and a regional evaporite seal.

D3 Energy stated that the same combination of geological components has been mapped at Hydrohelix and Cootanoorina using seismic data. This regional comparison has supported the company’s decision to progress the prospects through independent resource certification.

However, the reported concentrations from Mt Kitty-1 relate to a separate well outside D3 Energy’s prospects. They do not confirm that similar concentrations will be encountered within PEL121.

Drilling at Hydrohelix or Cootanoorina will be required to test the company’s interpretation and determine whether gas is present within the mapped reservoir settings.

South Australian Footprint Covers 5,865 Square Kilometres

PEL121 and PEL122 provide D3 Energy with a combined exploration position of approximately 5,865 square kilometres in the Arckaringa Basin.

The permits are located close to the Olympic Dam uranium deposit, which forms part of the broader regional geological setting referenced in the company’s exploration model.

D3 Energy holds a 100% interest in both permits, giving it control over exploration planning, technical studies and potential future commercial arrangements.

The maiden resource currently applies only to the Hydrohelix and Cootanoorina prospects within PEL121. It does not include the nine additional leads identified in that permit or any potential prospects within PEL122.

Accordingly, the current estimate represents the first independently certified resource assessment from the broader South Australian portfolio rather than a complete evaluation of the entire licence area.

The company intends to undertake further work to mature the remaining leads across both permits. Any future expansion of the resource base will depend on the outcome of technical studies and the ability to define additional prospects suitable for independent assessment.

Farm-Out Process Underway for Hydrohelix

D3 Energy has commenced a farm-out process for the Hydrohelix prospect to support future drilling.

A farm-out typically involves bringing in another party to contribute capital or technical support in exchange for an interest in a project. The announcement did not disclose the proposed terms, the interest potentially available or the timing for completion of any transaction.

The process is intended to assist with funding future drilling activity at Hydrohelix.

The independent certification may provide potential counterparties with a clearer technical basis for evaluating the prospect. However, no agreement has been announced, and the outcome of the process remains subject to discussions with interested parties.

D3 Energy has also not disclosed a drilling date, planned well depth or expected exploration cost for Hydrohelix or Cootanoorina in the latest update.

Further details are likely to depend on the outcome of the farm-out process, technical planning and any approvals required before drilling.

Second Geographically Diversified Resource Position

The PEL121 certification provides D3 Energy with a second Prospective Resource position outside its existing South African portfolio.

The company already holds helium and methane reserves and resources in the Free State of South Africa. The new South Australian estimate broadens its geographical exposure and adds hydrogen to the resource mix.

Managing Director and Chief Executive Officer David Casey described the certification as another milestone for the company and a further indication of the potential identified across PEL121.

He said Hydrohelix and Cootanoorina had been developed using seismic data that mapped the same combination of geological features found in the regional Mt Kitty-1 setting.

Management also highlighted the portfolio diversification created by having resource exposure across Australia and South Africa.

The announcement does not provide revised group-level resource totals combining the Australian and South African assets. It instead presents the PEL121 volumes as a separate maiden estimate for the Hydrohelix and Cootanoorina prospects.

Independent Certification Supports Exploration Model

Sproule ERCE completed the independent assessment of the maiden Prospective Resource.

Independent certification provides external technical evaluation of the available seismic interpretation, geological assumptions, reservoir parameters and potential recoverable volumes.

The certification supports the company’s geological model, but it does not eliminate exploration uncertainty. The estimated quantities remain dependent on a future discovery being made and on the subsequent ability to develop any discovered gas accumulation.

The company must still establish the presence of gas through drilling and testing. If a discovery is made, further appraisal work would be required to evaluate reservoir quality, gas composition, flow characteristics and recoverable volumes.

Commercial development would also depend on factors such as infrastructure, processing requirements, project economics, approvals, funding and potential sales arrangements.

As a result, the maiden resource represents an important technical step in progressing PEL121, while drilling remains the key requirement for determining whether the prospects contain recoverable helium, hydrogen and methane.

Remaining Leads Offer Scope for Further Assessment

In addition to Hydrohelix and Cootanoorina, D3 Energy has identified nine leads within PEL121.

These leads have not yet reached the same level of technical maturity as the two certified prospects. Further geological and geophysical work will be required before they can be classified as drill-ready prospects or included in a resource estimate.

The large combined permit area means D3 Energy’s current resource assessment covers only part of its South Australian exploration footprint.

Future work may focus on improving seismic definition, mapping structural closures, refining reservoir assumptions and evaluating the relationship between basement faults and prospective trapping configurations.

The announcement does not provide a timetable for maturing the remaining leads. It also does not specify whether additional seismic acquisition is required.

Nevertheless, management indicated that further work across PEL121 and PEL122 is intended to build on the maiden certification and assess the broader scale of the regional critical gas system.

What Does This Mean for Investors?

D3 Energy’s latest update provides an independently assessed starting point for its South Australian helium, hydrogen and methane portfolio.

The combined net 2U estimate of 54 billion cubic feet of helium, 88 billion cubic feet of hydrogen and 226 billion cubic feet of methane gives the company a defined Prospective Resource across Hydrohelix and Cootanoorina.

The certification also broadens D3 Energy’s geographical position beyond its existing South African assets and establishes a second resource base across a separate jurisdiction.

However, the volumes remain prospective and unrisked. No discovery has yet been confirmed at either prospect, and drilling is required to establish whether recoverable gas accumulations are present.

The Hydrohelix farm-out process is therefore an important next step because it is intended to support future drilling activity. Investors will also be watching for progress in maturing the nine additional leads across PEL121 and further technical work within PEL122.