South African startup SeaH4 has claimed the top prize at the ClimateLaunchpad Global Grand Final 2025, held in Vienna, Austria, for its breakthrough algae-based fuel innovation. The company triumphed over more than 2,700 entries from 40 countries, securing the €10,000 (US$12,000) award at the world’s largest green business idea competition.
Founded in 2022 by a team of environmental engineers, SeaH4 is developing sustainable biofuels derived from cultivated seaweed, specifically designed to decarbonize marine and aviation transport, two of the most challenging sectors to transition to net-zero. Their fuel is compatible with existing combustion engines, offering a scalable solution that extends the life of current infrastructure while reducing emissions.
SeaH4’s process integrates land-based seawater cultivation of Ulva algae, anaerobic digestion, and Power-to-X synthesis, producing a flexible hydrocarbon fuel with its own low-cost biogenic CO₂ stream. This approach avoids competition with freshwater and agricultural land, making it ideal for deployment along arid coastlines with abundant renewable energy.
The startup’s pitch impressed an international jury with its technical clarity, cost logic, and infrastructure compatibility, earning praise for its potential to scale rapidly and deliver real-world impact. SeaH4’s win positions South Africa as a rising leader in cleantech innovation, showcasing how locally developed solutions can address global climate challenges.
SeaH4’s team, including Gabrielle Ossinga (Head of Hydrogen and Biogas), Johann Heyns (Head of Legal), and Dhiren Vanmari (Aquaculturist), represented the company virtually at the Vienna finale, which marked the return of ClimateLaunchpad’s in-person event since 2019.
ClimateLaunchpad, powered by Climate KIC and supported by Bank of America and Irish Aid, has grown from a European initiative into a global platform supporting over 5,000 startups across 97 countries. In 2025, the programme expanded into nine new countries, including Argentina, Australia, Brazil, Japan, Singapore, Mexico, Peru, Hong Kong, and Vanuatu, and aims to reach 100 countries by 2030.
This year’s competition focused on eight key themes:
- Clean Energy
- Food Systems
- Circular Economy
- Blue Economy
- Sustainable Mobility
- Urban Solutions
- Adaptation and Resilience
- Emerging Innovations
SeaH4’s victory not only brings international visibility and investor access, but also opens doors to tailored support and global partnerships that will help scale its innovation. The startup is expected to create local jobs, drive skills development, and contribute meaningfully to South Africa’s green economy.
The next ClimateLaunchpad Global Grand Final will be held in Singapore in 2026, continuing the programme’s mission to empower climate entrepreneurs worldwide.
