RGreen backs French geothermal firm Arverne with €52.4M
What's the deal? French sustainable investment firm RGreen InvestDealroom has a profile for this one. Try Dealroom → has put €52.4 million ($59 million) into geothermal energy provider Arverne. The growth equity round, made through RGreen's holding company Geogreen, was led alongside Arverne founder and chief executive officer Pierre Brossolet.
What does Arverne do? Founded in 2018 in Pau, France, the company traces its drilling roots to 1958, when Arverne Drilling Services served the oil, gas, and mining sectors. Brossolet pivoted that expertise to deep geothermal drilling, extracting heat from underground. Arverne also owns 2gré, which sells geothermal heat, and Lithium de France, which extracts lithium from geothermal brines.
What has it built? Arverne's flagship project sits beneath Paris Charles de Gaulle Airport, where it drilled two wells generating up to 80 gigawatt-hours annually for Terminal 1. It later won a 30-year concession with DalkiaDealroom has a profile for this one. Try Dealroom → — valued at nearly €90 million — for a district heating network in two Paris suburbs, and formed a joint venture with the investment arm of French state-owned bank Caisse des DépôtsDealroom has a profile for this one. Try Dealroom → to develop projects across Île-de-France.
Why now? The French government wants to quadruple geothermal output to 28 terawatt-hours by 2035. EU member states voiced explicit support for the technology for the first time in December 2024, as a coalition of nearly 70 companies and investors pressed the European Commission for a dedicated strategy.
Investor thinking: RGreen Invest manages roughly $3.3 billion, focused on renewable energy infrastructure. Founder and chief executive officer Nicolas Rochon framed the deal around energy security, saying the firm is "delighted to partner with Arverne."
What could go wrong? Upfront capital risk is the sector's main barrier: exploration drilling costs tens of millions of euros with unpredictable results. Rystad EnergyDealroom has a profile for this one. Try Dealroom → puts exploration well failure rates between under 10% in Germany and 30% in the Netherlands. Public fears over drilling-linked earthquakes, after incidents in Basel and Staufen, add further friction.
The signal: The round lands in the 29th percentile by size — modest against the broader funding field, but notable for a still-nascent sector. Geothermal remains a small slice of Europe's energy mix, with district heating output up just 4.6% between 2023 and 2024. A deal of this scale signals investors are beginning to underwrite the deep-drilling bets that could unlock it.
Read more: Wedoany
