Clean tech startup Moonwatt has raised $8.3 million in seed funding to advance its solar-optimized battery storage system powered by sodium-ion technology. The Netherlands-based company, founded in September 2024, aims to enhance the efficiency and profitability of solar power plants by addressing the challenge of energy variability.
A Game-Changer for Solar Energy
The biggest challenge with solar energy is its inconsistent power generation—it only works when the sun is shining. Moonwatt’s battery-based energy storage system helps solar plants store excess energy produced during the day and release it during peak demand hours, increasing revenue potential.
Unlike traditional lithium-ion batteries, Moonwatt’s sodium-ion technology offers:
Lower costs (cheaper, more accessible raw materials)
Improved scalability
Reduced carbon footprint
While sodium-ion batteries are bulkier than lithium-ion, they are ideal for stationary solar plants, where space is not a constraint.
Doubling Solar Plant Returns
Moonwatt’s system allows solar plants to increase their capacity factor to 80% and double their internal rate of return (IRR).The company’s distributed storage architecture also makes it easier for solar plants to integrate the technology, reducing energy dispatch costs.
Backed by Industry Experts & Investors
Moonwatt’s founders—CEO Zukui Hu, CTO Guillaume Mancini, and CCO Valentin Rota—have a decade of experience in battery technology, including working at Tesla and battery manufacturer Freyr (now Ti Energy).
Their $8.3 million seed round was co-led by Daphni and LEA Partners, with participation from Founders Future, AFI Ventures, Kima Ventures, and strategic business angels.Next Steps: Pilot in 2026, Commercial Launch in 2027
Moonwatt plans to install its first pilot project in Europe in 2026, with full commercial deployments starting in 2027.
Their long-term ambition? Becoming a gigawatt-hour player, helping the solar industry scale further with cost-competitive, efficient energy storage solutions.