This week, we’ve got a quick roundup of the quarter’s highlights for you. Deal volume may have dipped, but investors doubled down on steel, concrete, and electrons. Check out the biggest deals, exits, and new funds of the quarter below.
Q3’s climate capital recap
The third quarter of 2025 saw a steady drumbeat of deals, even as broader markets contended with regulatory shifts and geopolitical turbulence. Investors seized on opportunities at the edges of macro trends to favor more scaled hardware, proven tech, and verticals aligned with energy security and AI/power demand. They doubled down on fewer, larger rounds in sectors with these clear demand signals and commercial pathways.
On the exit front, Q3 delivered more consolidation than celebration. Industrial incumbents snapped up enabling tech in cement and hydrogen, using M&A to secure upstream advantages and expand into climate-aligned verticals. Meanwhile, agtech and clean fuels saw smaller, quieter tuck-ins. With startup valuations down and capital more selective, acquirers are staying strategic.
Fundraising held steady, but the mood was cautious. Most new vehicles were targeted, regionally scoped, and heavy on infrastructure — a far cry from the generalist mega-funds of 2021. From commercial building retrofits to regenerative ag, LPs are favoring tangible assets, defined return profiles, and strategies that match today’s cost of capital.
Let’s break down the quarter.
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Q3 2025 highlights
💰 Mega-deals in the built environment and energy topped the charts – with three >$500m raises and seven companies securing $200m+, even though overall deal volume remained low. Hardware-heavy climate tech is back in favor, but mostly where clean power meets digital infrastructure.
🏠 Built environment tech took the top and bottom slots. Nscale ($1.1bn for low-carbon data centers) and Torus ($200m for smart homes) bookended the leaderboard. Firmus also raised $330m for AI-optimized immersion-cooled data centers.
⚛️ Fusion, batteries, and grid storage saw major momentum. Commonwealth Fusion raised $863m, Group14 closed a $463m Series D, and Eelpower picked up $675m to scale UK battery storage projects.
Mobility kept moving, with VEMO ($250m) and Also ($200m) clean transport across Mexico and the US. Carbon removal was quiet, with only Climeworks making the list — $162m for its solid sorbent DAC tech.
📈 IPOs came back — selectively. Via went public at a $3.6bn valuation, and TruAlt Bioenergy raised $123m on India’s ethanol mandate. Deep Fission also took a (confusing) SPAC detour.
💸 Funds stayed focused and local. Nuveen Green Capital led with a $785m close for C-PACE commercial real estate. Other new funds focused on early-stage, ag, materials, and electrification.
Top deals
Taken together, Q3’s biggest deals show climate capital continuing to flow toward infrastructure-heavy solutions — especially those with clear regulatory support, commercial offtake potential, or relevance to the energy-AI nexus. A lot of the quarter’s heat comes from hyperscaler infrastructure and fusion, where large, late-stage, or strategic rounds dominate the top decile.
Top exits
Q3 was marked by a wave of strategic M&A, led by industrial buyers consolidating critical technologies and bigger startups scooping up smaller ones. Baker Hughes’ acquisition of Chart Industries folded its tech for gas, hydrogen, and liquid handling into its energy systems portfolio. CRH’s $2.1bn purchase of Eco Material Technologies secured upstream cement inputs as the construction sector bets on decarbonization. Electric Hydrogen’s quiet acquisition of Ambient Fuels, though undisclosed, looks like an IP and pipeline grab to speed up execution. Even in agtech, where outcomes are smaller, exits continued quietly with Trace Genomics and Daring changing hands.
Yes, real IPOs happened this quarter. But the quality varied. Via made a debut, listing at a $3.6bn valuation and becoming one of the largest publicly traded transportation optimization companies in the US. TruAlt Bioenergy raised $123m on the strength of India’s ethanol mandate — continuing a regional trend of public market momentum. On the other end of the spectrum, Deep Fission’s $30m SPAC felt more like a nuclear publicity play than a commercial milestone. If anything, Q3’s listings showed that scale, revenue, and regulatory clarity are still prerequisites for serious IPOs — and that investor appetite remains cautious outside a handful of proven verticals.
Sadly, Q3 also saw more bankruptcies, especially in high capex sectors. Natron Energy, with over $300m in funding , filed for bankruptcy after 18 years and $325m raised, proving how hard it is for alternative chemistries to break lithium-ion’s grip. VoltStorage quietly shut down after nine years and $32m, another victim of scale barriers in storage. And in carbon removal, Noya folded after just five years and $12m raised, a cautionary tale of how unforgiving direct air capture can be without deep pockets, stable offtake, and policy support.
Top new funds
Fresh capital entered the sector — but new funds are more focused, more local, and more infrastructure-aligned. Nuveen Green Capital led the pack with a $785m close for C-PACE financing, targeting energy efficiency, water conservation, and climate resilience projects in commercial real estate. The rest of the quarter’s top funds flowed into highly specific themes: Circulate Capital’s $76m LAC fund for circular economy solutions in Latin America, VoLo’s $135m fund with an early-stage remit, and more ag- and mobility-focused funds from Mad Capital and Vireo Ventures. While headline numbers were smaller than past quarters, LPs are still backing funds with tangible deployment targets.
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