Cleantech Group’s annual list highlights 50 early-stage companies charting new pathways for resilience, efficiency, and growth across cleantech markets
October 15, 2025
Darcy Solutions is thrilled to be named on Cleantech Group’s prestigious 2025 Cleantech 50 to Watch list. The list spotlights the early-stage companies poised to deliver breakthrough solutions to the world’s most pressing climate and sustainability challenges.
Selected from hundreds of nominations worldwide, the 50 companies represent the most compelling innovators at the intersection of technology, business, and impact.
This year’s Cleantech 50 to Watch emerges against a backdrop of heightened geopolitical and economic uncertainty. Global tariffs, policy reversals, and development bottlenecks continue to reshape project timelines and investment flows. Yet, even amid these headwinds, a new generation of entrepreneurs is redefining what is possible—accelerating advances in clean energy, sustainable materials, food and agriculture, and digital-enabled climate solutions.
“As we’ve seen throughout 2025, innovation doesn’t stand still,” said Anthony DeOrsey, Research Manager at Cleantech Group. “These 50 companies represent where the market is heading next: increasing sophistication of AI, new frontiers in resource resilience, and breakthrough solutions in consumer goods sustainability. Their work shows us not just what’s possible, but what’s urgently needed.”
“Being named to the Cleantech 50 To Watch list is an amazing validation of the groundbreaking work our team at Darcy Solutions is doing to deploy geothermal systems globally,” said Andrew Steiner, CEO at Darcy Solutions. “Our focus has always been to make high-performance, sustainable heating and cooling the standard expectation for commercial HVAC systems. This recognition from the Cleantech Group highlights that delivering high-capacity geothermal systems in limited footprints is exactly the kind of disruptive technology needed to accelerate the global transition to a decarbonized built environment.”
At the beginning of the year, Cleantech Group introduced a “Grow, Flow, Slow” framework to identify which technologies are likely to accelerate, advance steadily, or encounter significant headwinds. Updated throughout the year, the framework continues to highlight the dynamic forces shaping cleantech markets.
Within this landscape:
- Grow categories include energy-efficient compute, sources of clean baseload power, and technologies for lower footprint critical minerals access.
- Flow areas include sustainable aviation fuels, green steel, and distributed ammonia fertilizers—sectors moving forward but with important nuances.
- Slow areas, such as alternative proteins and some hydrogen applications, face structural and market headwinds requiring new strategies to scale.
Energy-Efficient Compute – The Next Frontier
More companies than ever are innovating across the compute efficiency value chain, from novel semiconductors to rack-level power management. Notable examples include:
AI as a Climate Enabler
Artificial intelligence is driving innovation not only in software but also in physical systems and deep tech. Companies like Entalpic, Juna AI, and Beyond Weather are showcasing AI’s transformative potential across industries.
Crop Science for Resilience
With agriculture increasingly threatened by climate volatility, innovators are turning to bio-based and nanotechnology-driven solutions. Companies such as IMIO, NetZeroNitrogen, Silvec Biologics, and Qarbotech are advancing treatments that improve yields while reducing environmental impact.
Consumer Goods Sustainability
For the first time, consumer goods cleantech has a strong foothold in the Cleantech 50 to Watch. Eight companies—including re.solution, Syntetica, Radical Dot, and Sengong—are pioneering advanced recycling and novel materials to address textiles, plastics, and waste streams long considered unrecyclable.
The Importance of Ecosystems
The 2025 Cleantech 50 to Watch also highlights the role of innovation ecosystems in supporting early-stage growth. Regional accelerators, public agencies, and venture platforms—including SGInnovate (Singapore), Innovate UK, and Greentown Labs (Massachusetts)—are playing a critical role in helping start-ups access markets, partners, and capital.
Looking Ahead
This year’s honorees reflect the cleantech sector’s resilience and ingenuity in the face of global uncertainty. From AI-driven breakthroughs to novel approaches in recycling and agriculture, the Cleantech 50 to Watch demonstrates that innovation continues to push boundaries, even in turbulent times.
“We congratulate all 50 companies recognized this year,” said DeOrsey. “Their progress shows that the path to a low-carbon, resource-efficient future is not only alive but accelerating in unexpected and exciting ways.”
Download your complimentary copy of the 2025 Cleantech 50 to Watch list and supplementary report here.