Amsterdam’s Moonwatt secures €7.6M to scale solar-only storage with sodium-ion batteries
Amsterdam-based Moonwatt, a company building solar-only energy storage systems using sodium-ion batteries, has secured $8.3M (approximately €7.6M) in funding in a Seed round.
The seed round is co-led by Daphni and LEA Partners, with participation from Founders Future, AFI Ventures (by Ventech), and Kima Ventures, alongside strategic business angels and customers.
The Dutch company will use the funds to launch its storage technology with a pilot installation in Europe next year, expecting to start commercial deployments by 2027.
Moonwatt: Develops a battery storage system
Led by CEO Zukui Hu, Moonwatt develops a battery storage system designed to work alongside solar power plants.
The system helps manage energy fluctuations using specially designed battery enclosures, inverter electronics for grid connection, and software to control storage and distribution.
According to the company, this approach allows solar plants to increase revenue by selling more energy when prices are higher and lowering costs by sharing electrical infrastructure.
The system is intended for solar plants producing at least a few hundred kilowatts of energy, excluding small residential solar installations.
At the heart of Moonwatt’s mission is the utilisation of sodium-ion battery technology.
Sodium-ion batteries are becoming popular because they can help with the reliability of renewable energy sources.
Although sodium-ion batteries are larger and heavier than lithium-ion, making them less suitable for applications like electric vehicles, they offer a practical solution for stationary solar power storage where space is not a constraint.
The storage system is designed in a distributed way, making it easier for plants to integrate. This setup is expected to improve efficiency and lower the costs of dispatchable electricity by connecting storage units closer to the solar panels during peak output.
According to the startup, its approach can help solar power plants make more money by selling more solar energy, especially when prices are higher. It also aims to cut costs by sharing some electrical infrastructure.
The target plants are those producing several hundred kilowatts or more, not including residential solar systems.
“Basically, what we allow our partner to do is to double their return,” co-founder and chief commercial officer, Valentin Rota, tells TechCrunch. “So in AAA [credit-rating] country, I would say an average PV [photovoltaic] asset is around, let’s say 8 per cent to 12 per cent return — IRR — and we will bring the asset up to around 20 per cent.”
Moonwatt offers a storage system that can increase a solar plant’s capacity factor up to 80 per cent. Plants that use this system might be able to double their internal rate of return (IRR), reports Tech Crunch.
“We started to see this application first starting on what we call microgrids, so usually a small grid-resistant generator,” says Rota. “But as the cost of batteries went down and the cost of storage went down actually those applications started to arrive in bigger countries on bigger grids, and it’s really driven by the fundamental pace of solar.”