Vulcan Energy Well Confirms Matrix Injection Potential at Lionheart Project
Key Takeaways
- LSC-3a, the seventh of 28 planned wells, is Vulcan's first to re-inject brine into the sandstone matrix, testing a core assumption of the 2023 Bridging Study base case.
- Interpreted injection capacity of about 64 sL/s at 70 barg and 65°C sits well above the roughly 40 sL/s assumed in the Field Development Plan.
- The measured surface rate was about 35 sL/s at 69 barg and 18°C, so the 64 sL/s figure rests on downhole data and wellbore modelling.
- Results across all seven wells have thus far met or exceeded plan assumptions, though the company expects variance and one strong well guarantees nothing for the other 21.
- LSC-3a data will shape the LSC-4 and LSC-5 reinjection wells, but the announcement gives no costs or timelines for those steps.
LSC-3a well test confirms matrix injection at Project Lionheart
Vulcan Energy (ASX: VUL) has completed LSC-3a, the seventh well in the planned 28 well Field Development Plan for Project Lionheart. It is Vulcan’s first well to re-inject brine back into the matrix of the sandstone reservoir.
The well was completed by Vulcan’s in-house drilling company, Vercana. The company describes the result as an important execution de-risking milestone.
For investors, the key point is what the test checks. The company says it provides direct field validation of matrix injection, which is key evidence supporting the base case production scenario.
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Injection capacity of 64 sL/s beats the 40 sL/s assumption
The interpreted injection capacity of about 64 standard litres per second (sL/s) sits well above the roughly 40 sL/s assumed for matrix injectors in the Field Development Plan. Here is how the test played out.
Test results
- LSC-3a is a geo-steered horizontal well drilled to a total measured depth of 3,743m.
- It was drilled during September 2026 and tested in early October 2026.
- It achieved a measured surface injection rate of approximately 35 sL/s at 69 barg wellhead pressure and 18°C.
- Interpretation of the test data indicates an injection capacity of approximately 64 sL/s under planned operating conditions of 70 barg wellhead pressure and 65°C wellhead temperature.
The 64 sL/s figure is interpreted, not measured. It draws on downhole pressure and temperature measurements and wellbore modelling, so the measured rate remains 35 sL/s.
| Metric | Plan assumption | LSC-3a result |
|---|---|---|
| Matrix injector rate (interpreted, planned operating conditions) | ~40 sL/s | ~64 sL/s |
| Matrix injector rate (measured at test conditions of 69 barg and 18°C) | N/A | ~35 sL/s |
The two rows reflect different conditions. The interpreted figure applies to planned operating conditions, while the measured rate came from the test itself.
Why the pilot hole mattered
An initial pilot hole, LSC-3, was drilled first. It confirmed the location and quality of a higher-permeability reservoir interval previously encountered in LSC-1 and LSC-2, and the horizontal LSC-3a was then drilled to maximise exposure to that interval.
Cris Moreno, Managing Director and CEO
“Every milestone we deliver reduces risk and moves us closer to first commercial production…”
What matrix injection means for investors
Lithium brine projects work in pairs of wells. Producers extract hot lithium-rich brine, and injectors return the lithium-depleted, cooled liquid to the subsurface.
Until now, Vulcan’s historical production and reinjection occurred in the fault zone. LSC-3a is the first well to test reinjection into the reservoir matrix, the sandstone rock itself.
That matters because the 2023 Bridging Study assumes a combined matrix and fault reinjection program. The company says reinjecting into the matrix validates the potential to use lithium-depleted brine to push and actively sweep larger portions of the underground formation to increase lithium recovery.
In plain terms, the result reduces uncertainty around long-term reservoir pressure support and lithium brine sweep efficiency. Those are two of the subsurface questions that bear on how well the field can perform over time.
The company points to the following supporting evidence:
- Updated seismic imaging, calibrated through drilling and logging results, has improved reservoir prediction capability and increased well placement confidence.
- Drilling, core and logging data confirm a laterally persistent, higher-permeability reservoir interval across multiple wells.
- Production and reinjection test results across the three new wells, alongside the four existing wells (seven in total), have thus far met or exceeded the assumptions underpinning the Field Development Plan.
For balance, the company expects some variance across the program. One strong well does not guarantee every future well will match it.
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Lionheart scale and next steps
Project snapshot
Located in the Upper Rhine Valley Brine Field between Germany and France, Lionheart is Vulcan’s first phase of production. The following are Bridging Study targets, not achievements:
- Target production capacity of 24,000 tonnes per annum of lithium hydroxide monohydrate (LHM), enough for ca. 500,000 electric vehicle batteries per annum.
- A co-product of 275 GWh of renewable power for internal consumption.
- 560 GWh of heat per annum for local consumers.
- An estimated 30-year project life.
What comes next
The LSC-3a results will be incorporated into the integrated geological and dynamic reservoir interpretation. They will guide the design and execution of the subsequent LSC-4 and LSC-5 reinjection wells as part of the overall Lionheart construction program.
The company says additional optimisation opportunities are being investigated, with the objective of enhancing project value. The announcement does not disclose costs or timelines for these steps.
Management says it remains firmly focused on execution and on delivering a new local, low-cost, battery-grade lithium supply chain from Europe, for Europe.
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