Graz–OMV geothermal halt highlights public–private divide

Picture: City center of Graz, Austria (source: Bernd Thaller CC BY 2.0 , via Wikimedia Commons)

Alexander Richter 12 Nov 2025

OMV’s exit from the Graz geothermal project may seem local, but it signals a wider European problem: how to align private capital with municipal utilities to scale geothermal heating.

This week, Austrian energy group OMV announced its withdrawal from the planned 140 MWth geothermal district heating project for the city of Graz, citing the city’s failure to approve resolutions assuming liabilities of over EUR200 million.

The project had aimed to supply up to 500 GWh of renewable heat annually by 2030, serving the greater Graz area through a joint venture between OMV Green Energy GmbH, Energie Graz, and Energie Steiermark.

Graz Mayor Elke Kahr defended the city’s decision, arguing that the proposed agreement would have left Graz merely as a heat purchaser while carrying unlimited financial liability, something neither permissible under municipal law nor acceptable to taxpayers.

Within hours of OMV’s announcement, Energie Steiermark offered EUR120 million to acquire the city’s district heating network to continue with OMV’s original concept. The city rejected the offer, reaffirming its intent to maintain public ownership of critical energy infrastructure.

A project that promised much — and a partnership that collapsed

At its core, the Graz geothermal project was designed to tap deep resources beneath Styria to deliver reliable, low-carbon heat for decades.

Seismic surveys were planned for late 2025, with a first exploration well expected in 2026.

Yet, despite the strong technical basis, the financial and governance framework failed before a single well was drilled.

According to OMV, the absence of formal city resolutions left the project without the required guarantee structure to secure financing. For municipal partners, the liability exposure proved politically and legally impossible.

Why this matters beyond Graz

While this dispute may appear uniquely Austrian, it reflects a pan-European bottleneck in geothermal heating:  How can private developers and public utilities share risk in a way that enables investment while preserving public accountability?

Municipalities often want to maintain full ownership and control of their heat networks, reluctant to hand long-term supply contracts to private players, even those willing to take exploration and development risk. Yet this reluctance creates a paradox: cities neither wish to bear the early-stage risk nor to compensate private investors through stable, long-term offtake agreements. The result is that many promising projects stall in governance, not geology.

Key friction points:

• Risk allocation: Early-phase geothermal exploration carries high uncertainty; cities cannot shoulder open-ended liabilities.

• Ownership vs. control: Heat networks are strategic municipal assets, yet investors seek stability through long-term offtake or operational control.

• Decision speed: Public approval cycles move slower than private financing windows.

• Public perception: Temporary tariff increases during construction can overshadow long-term stability benefits.

Lessons for future geothermal heat partnerships

1. Stage guarantees to milestones, not blanket liabilities. Municipalities can commit in phases — after seismic confirmation, after first production tests — reducing political and financial exposure.

2. Regional or national risk-sharing facilities. Countries like France and the Netherlands show that guarantee schemes and risk insurance can unlock capital without overburdening cities.

3. Transparent tariff modeling. Showing how geothermal heat stabilizes consumer prices against fossil volatility builds public trust.

4. Hybrid governance models. Public ownership of heat grids can coexist with private investment through concession or availability structures that ensure accountability.

These new governance models also need to recognize that most municipalities simply lack the in-house expertise, capital, and project-management depth required to develop geothermal heating systems on their own, and compete in a tight market for qualified talent and drilling know-how.

A European reflection

The Graz case is not about geology – it’s about governance, capacity, and the limits of municipal control.

If Europe wants to expand geothermal heat at scale, cities cannot remain the only risk absorbers. Private partners must accept structured, capped exposure, while higher levels of government provide early-stage de-risking.

The opportunity remains enormous: geothermal heating offers secure, low-carbon baseload energy for urban centers across the continent.

But without better frameworks for public-private collaboration, even the most promising projects risk stalling before reaching the subsurface.

Project snapshot

• Planned capacity: 140 MWth
• Expected annual output: 400–500 GWh heat
• Target start:2030–2031
• Partners: OMV Green Energy GmbH, Energie Graz, Energie Steiermark
• Reason for withdrawal: Lack of municipal liability resolutions (>EUR200 m)
• Status: On hold as of Nov 2025

Author’s note:

This editorial commentary is part of ThinkGeoEnergy’s ongoing analysis of market dynamics in geothermal power and heating.

For more insights on public–private cooperation models in Europe’s geothermal sector, see our regular news coverage and follow us on LinkedIn.

Based on the recent news published by ThinkGeoEnergy, and sources: Kleine Zeitung (1 and 2), Energate Messenger, MeinBezirk, and SteierMark.