When Siemens Bets Big, Geothermal's Industrial Era Begins

Siemens and Vulcan Energy: The Automation Backbone of Europe's Geothermal Lithium Revolution

By Alphaxioms Geothermal Insights | April 2026

Image: The Vulcan Geothermal Lionheart Field 

On 20 April 2026, Vulcan Energy Resources (ASX: VUL, FSE: VUL) announced the signing of a circa €40 million framework agreement with Siemens AG, appointing the German industrial giant as Main Automation Contractor (MAC) for its flagship Lionheart Project in Germany's Upper Rhine Valley. This announcement, which Vulcan describes as the final major supply agreement for Lionheart, deserves far more analytical attention than a routine procurement notice. It is, in fact, a milestone that illuminates the trajectory of geothermal energy as an industrial foundation not merely a power source  and carries instructive lessons for geothermal developers across every active rift zone on the planet, including the East African Rift Valley.

What Lionheart Actually Is

To understand the significance of the Siemens agreement, one must first appreciate what the Lionheart Project represents in the broader energy transition architecture. Lionheart is not a geothermal power plant in the conventional sense. It is an integrated geothermal-lithium extraction and processing complex targeting the production of 24,000 tonnes of lithium hydroxide monohydrate (LHM) per annum — enough to supply batteries for approximately 500,000 electric vehicles every year — while simultaneously generating 275 GWh of renewable power and 560 GWh of heat as co-products, delivered to local consumers over an estimated 30-year project life.

The feedstock is geothermal brine extracted from the Upper Rhine Valley's subsurface brine field at depths of approximately 3 kilometres. The brine is lithium-rich and low in impurities — an exceptional geological endowment that Vulcan exploits using its proprietary VULSORB® direct lithium extraction (DLE) technology. After lithium is stripped from the brine at the Geothermal and Lithium Extraction Plant (G-LEP) in Landau, the depleted brine is reinjected and the geothermal heat is harvested for power production and district heating. The lithium chloride intermediate product is then transported to the Central Lithium Plant (CLP) at Industrial Park Höchst in Frankfurt, where it is converted into battery-grade LHM for delivery to European customers including LG Energy Solution, Umicore, Stellantis, and Glencore.

Image:When Siemens Bets Big, Geothermal's Industrial Era Begins

This is a vertically integrated, geothermally powered critical minerals supply chain — arguably the most sophisticated deployment of geothermal energy in industrial history.

Why Automation Is the Nervous System of This Project

A project of Lionheart's complexity does not run on passion or capital alone. It runs on data, control logic, and coordinated machine intelligence. The distributed nature of Lionheart — geothermal well sites, an upstream extraction plant in Landau, a downstream conversion plant in Frankfurt, and the pipeline infrastructure linking them — creates an operational coordination challenge that would be unmanageable without industrial-grade automation architecture.

This is precisely why the appointment of Siemens as MAC is strategically significant. As MAC, Siemens is not merely supplying equipment. It is responsible for the engineering and delivery of the distributed control system (DCS), the industrial network and cybersecurity infrastructure, building automation, and safety systems across all three areas of the project. It is, in engineering terms, providing the nervous system that will allow Lionheart to function as a single coordinated organism rather than a collection of disconnected plants.

For geothermal projects specifically, automation depth matters enormously. Geothermal wells are dynamic systems. Reservoir pressure, fluid temperature, brine chemistry, and flow rates fluctuate over time and with operational decisions. A DCS that integrates well performance data with extraction plant operations and grid export in real time is not a luxury — it is the difference between a project that optimises its resource and one that wastes it. At the wellhead level, automation governs pump scheduling, anti-scaling protocols, reinjection management, and safety shutdowns. At the plant level, it governs heat exchanger performance, turbine dispatch, and chemical dosing for the DLE circuit. At the enterprise level, it feeds the data historians and analytics platforms that allow operators to make informed decisions about resource stewardship over decades.

Siemens brings precisely this capability. With decades of experience deploying SCADA, DCS, and industrial IoT infrastructure across oil and gas, chemicals, power generation, and mining globally, Siemens is not learning on the job at Lionheart. Its local presence in Germany, its familiarity with the regulatory environment, and its existing relationship with Vulcan — formalised through a 2025 Memorandum of Understanding designating Siemens as preferred supplier through 2035 — mean the technical and commercial risk of this appointment is substantially de-risked from day one.

The Strategic Architecture of the Siemens Relationship

The Siemens-Vulcan relationship is more layered than a straightforward supply contract. Three distinct dimensions merit attention.

First, the financial dimension. Siemens Financial Services committed €67 million as part of Vulcan's €2.2 billion financing package secured in December 2025, comprising €60 million in base equity and €7 million in standby equity. This means Siemens is not just a contractor  it is a co-investor with a direct financial stake in Lionheart's success. When a technology and automation provider has equity skin in the game, the alignment of incentives between supplier and developer becomes unusually strong. Siemens has every reason to ensure that its automation systems perform reliably, that commissioning is smooth, and that operational uptime is maximised. This structure represents sophisticated project finance architecture that many emerging market geothermal developers would do well to study.

Second, the preferential supplier dimension. The 2025 MOU designating Siemens as preferred supplier through 31 December 2035 extends the relationship well beyond Lionheart's initial construction phase and into future development phases. Vulcan has signalled ambitions for further phases of production, and the Upper Rhine Valley brine field has significant additional resource potential. By locking in Siemens as a long-term technology partner, Vulcan is building institutional knowledge continuity  the automation systems of Phase One will inform the design of Phase Two, reducing engineering costs and integration risk as the project scales. This is the kind of long-term systems thinking that separates well-capitalised geothermal developers from project-by-project opportunists.

Third, the contractual architecture. The Siemens Agreement comprises three separate contracts on identical general terms  one each for the Lithium Extraction Plant, Central Lithium Plant, and production well sites  structured on a framework basis allowing Vulcan to issue purchase orders for discrete packages of work on a staged basis. This is elegant project management design. Rather than committing the full €40 million upfront against a single monolithic contract, Vulcan retains flexibility to sequence automation delivery alongside construction milestones. Cash flows are better managed, scope can be refined as construction progresses, and Siemens has a defined commercial pipeline against which to resource its delivery teams. The minimum aggregate purchase commitment of €40 million gives Siemens revenue certainty while the framework structure preserves Vulcan's operational agility.

Geothermal Intelligence Implications: What This Means Beyond Europe

For geothermal practitioners, investors, and policymakers watching from outside Europe, the Vulcan-Siemens milestone carries several important signals.

Geothermal is maturing into an industrial asset class. The involvement of a company of Siemens AG's scale  €78.9 billion in fiscal 2025 revenue, 318,000 employees globally as both automation contractor and equity co-investor in a geothermal project represents a qualitative shift in how the world's leading technology companies perceive the sector. Siemens does not take equity positions in nascent technologies with uncertain commercial trajectories. Its participation in Vulcan's financing package signals institutional confidence in geothermal-powered industrial production as a bankable, scalable proposition. This confidence, once established in Germany, has a way of migrating across geographies and asset classes.

Direct lithium extraction changes the geothermal value proposition fundamentally. Vulcan's VULSORB® DLE technology is the commercial-scale proof point that geothermal brines are not just a heat source but a polyvalent resource. The Upper Rhine Valley brines yield both renewable energy and battery-critical lithium in a single integrated operation. East Africa's geothermal brines  particularly in the Kenyan Rift  contain elevated concentrations of not just lithium but also silica, potassium, and in some cases rare earth elements. The resource intelligence question that African geothermal developers and their financiers have not yet answered systematically is: what else is in the brine, and what is it worth? Vulcan's model demonstrates that answering this question can transform the economics of a geothermal project and attract a completely different category of investor  critical minerals funds, battery supply chain players, and strategic industrials who have no historical interest in megawatt-hours but have intense interest in battery-grade lithium hydroxide.

The financing architecture of Lionheart is a model for African project development. Vulcan's €2.2 billion financing package  assembled with DFI participation, strategic equity from offtake partners, and technology provider co-investment including Siemens Financial Services  demonstrates that large, complex geothermal projects can be bankably financed when the technical risk is sufficiently de-risked, the offtake is contracted, and the supply chain is assembled with institutional-grade counterparties. The lesson for East African developers is not that this exact structure can be replicated tomorrow  it cannot  but that the pathway to it is sequenced and learnable. Feasibility studies lead to engineering studies lead to pilot operations lead to contracted offtake lead to DFI mandates lead to strategic co-investment. The discipline is in the sequencing.

Construction Is Underway: What Comes Next

With the Siemens Agreement signed, Vulcan confirms that all major supply agreements for Lionheart are now in place. The upstream Lithium Extraction Plant in Landau is already under construction. The Final Investment Decision was positive. Offtake is contracted. The financing is closed.

What follows is the grind of project delivery one of the most demanding phases of any large industrial development. The engineering, procurement, and construction (EPC) phase of a project of Lionheart's complexity will test the robustness of every supply agreement, every interface specification, and every project management system. Commissioning a geothermal wellfield, an extraction plant, a 400-kilometre-equivalent brine circuit, and a downstream chemical conversion plant simultaneously  while meeting regulatory requirements across two German federal states is not a trivial exercise. The Siemens framework agreement, with its 24-month warranty provisions, advance payment guarantees, liquidated damages clauses, and mutual indemnity structures, reflects hard-won knowledge about where industrial projects fail and how to allocate risk appropriately.

For Vulcan's investors and partners, the key near-term milestones will be first brine production from commercial wells, commissioning of the DLE circuit, and first production of lithium chloride intermediate  each of which represents a de-risking event that will test the automation systems Siemens is now contracted to deliver.

A Closing Observation on the Geography of Innovation

There is something historically resonant about the Upper Rhine Valley as the site of Europe's geothermal-lithium revolution. The Rhine Graben is a continental rift structure  geologically kin to the East African Rift System, though far older and more tectonically quiescent. Both are products of the same planetary process: the pulling apart of continental crust, the upwelling of heat, and the concentration of mineral-rich fluids in the resulting basins. The Upper Rhine Valley has hosted human settlement, agriculture, and industry for millennia, and its geothermal resource has been known for decades. What changed was not the geology  it was the technology, the capital, and the strategic will to integrate geothermal heat into a 21st-century industrial value chain.

In the East African Rift Valley, the geology is younger, hotter, and in many respects more energetic. The resource is larger. The strategic need  for domestic energy, for critical minerals, for industrialisation  is more acute. What is still being assembled is the technology stack, the institutional capacity, and the financing architecture to do for East Africa what Vulcan Energy is doing for Germany.

The Siemens-Vulcan agreement is a data point in that assembly. It tells practitioners in Nairobi, Addis Ababa, Kigali, and Dar es Salaam what the finish line looks like  and it tells them that the path there runs through demonstrated technology, contracted offtake, institutional-grade supply chain assembly, and the patient, sequenced work of turning a geothermal resource into an integrated industrial platform.

See also: Vulcan Energy Secures Landmark Lithium Production Permit for Lionheart

That work is already underway in East Africa. The question is the speed of assembly.

This article was produced by Alphaxioms Geothermal Insights. Alphaxioms Group is a global geothermal intelligence and deal facilitation platform headquartered in Nairobi, Kenya, with primary focus on the  Global Geothermal For intelligence, deal facilitation, and market advisory services, visit alphaxioms.com.

Source: Vulcan Energy Germany 

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