Moonwatt is building sodium‑ion hardware and software energy storage systems designed specifically to make solar dispatchable around the clock. The company was founded by energy veterans with experience at Tesla, EDF, Siemens, Scatec, and Freyr Battery. Its product strategy is to co‑locate storage with solar plants to boost usable capacity from roughly 15–20% to about 80%, reducing the need for costly grid upgrades and cutting congestion. Moonwatt emphasizes sodium‑ion chemistry as a more abundant, cheaper, and safer alternative to lithium‑ion for stationary storage. The recent €8 million raise will accelerate development and deployment of its technology, expand the team, and support commercialization efforts. Moonwatt positions its optimized solar-plus-storage approach as a pathway to scale renewables and materially reduce CO2 emissions by midcentury. Moonwatt develops a battery‑based energy storage system specifically designed to be co‑located with solar power plants, combining dedicated battery enclosures, inverter power electronics and management software. Its system is built around sodium‑ion cells to reduce raw‑material costs and carbon footprint compared with conventional lithium‑ion solutions, targeting stationary solar installations where size/weight are less constraining. The product uses a distributed architecture to simplify integration and mutualize electrical infrastructure, aiming to increase solar plants' capacity factor up to 80% and materially boost asset IRR. Target customers are non‑residential PV plants producing at least a few hundred kilowatts. The founding team — CEO Zukui Hu, CCO Valentin Rota and CTO Guillaume Mancini — previously worked together on battery technology at Tesla and at Freyr (now Ti Energy). Moonwatt plans a pilot installation in Europe next year and expects first commercial deployments in 2027 as it scales toward gigawatt‑hour ambitions.

Total raised

$19M

Funding rounds

2

Latest round

Equity

Latest activity

Mar 2025