As the sector matures from aspiration to deployment, European startups are proving that sustainability and commercial viability are no longer mutually exclusive – they're inseparable
When Deutsche Telekom's board met Marvel Fusion at 4YFN24, the conversation moved from introduction to investment in months. T-Capital joined the fusion energy pioneer's Series B round, transforming a Barcelona conference room conversation into a strategic partnership.
This is the power of 4YFN's Climate Tech track – where Europe's utilities, manufacturers and municipalities meet the startups building the infrastructure they urgently need.
As the climate tech sector matures from the record-breaking 2023 investment levels, the industry has evolved beyond early-stage experimentation into a mature ecosystem where investors back proven business models rather than speculative ventures.
A huge part of this future is focused on clean tech. Whilst climate tech focuses specifically on decarbonisation and adaptation, clean tech includes the full environmental infrastructure stack: water purification and management, air quality monitoring, waste reduction and circular economy systems, resource efficiency and sustainable materials, alongside renewable energy and carbon management.
The ventures being showcased at 4YFN26 will be those building platforms that tackle multiple environmental pressures simultaneously, recognising that climate, water and resource security are inseparable challenges. The energy-hungry rise of AI has also created a bottleneck – data centres need abundant, clean and reliable energy to operate, which is why solar, storage and optimisation solutions are attracting premium valuations.
Clean energy investment now stands at $2.2 trillion in 2025 – double the $1.1 trillion being spent on oil, gas and coal. Solar dominates the field, with combined spending on utility-scale and rooftop solar projected to reach $450 billion in 2025 alone, making it the single largest item in global energy investment.
Battery storage deployment is accelerating rapidly, with investment exceeding $65 billion globally, whilst startups like Ubiquitous Energy are embedding solar generation into everyday surfaces and companies like CarbonCure are decarbonising concrete production.
The transformation extends beyond renewable energy into circular economy infrastructure. European companies leading this infrastructure buildout include Greyparrot and Recycleye (UK-based AI waste sorting), Orcan Energy (Germany, industrial heat recovery), Enogia (France, thermal energy), Climeon (Sweden, clean power from waste heat), and Gamaya (Switzerland, precision agriculture).
This European innovation is drawing global infrastructure operators to 4YFN26, including K Water, South Korea's public water resources corporation. Their management of multipurpose dams and Korea's integrated water resource network exemplifies the systematic environmental resilience that Barcelona's clean tech ecosystem enables.
Clean tech is also converging with AI advancement, with startups deploying machine learning for predictive maintenance of renewable assets, optimising grid stability with real-time demand forecasting, and using satellite imagery combined with computer vision to monitor deforestation and methane emissions at unprecedented scale.
Recent funding patterns reveal both challenges and institutional confidence. European climate startups secured €2 billion in Q1 2025, representing a five-year low but with notably concentrated investment in later-stage rounds – signalling that whilst capital has become more selective, investors are backing proven revenue models.
The startups showcased at 4YFN26's Climate Tech track aren't chasing carbon credits – they're building the physical and digital infrastructure that cities, utilities and industries need to function sustainably. From AI-powered waste sorting to next-generation fusion energy, these are the companies turning the €2.2 trillion clean energy transformation into commercial reality.
Discover the future of clean tech infrastructure at 4yfn.com/climate-tech
Track Tags: Climate Tech, Infinite AI, Corporate Innovation, Clean Tech, Investors