Through electrification and clean energy, the power of battery technology continues to generate power to decarbonize our economy, as storage plays a key role in achieving a green transition. Renewables are clean energy sources compared to burning fossil fuels, but their power output is not always consistent. If solar energy (the deployment has increased significantly in recent years), the generation will be turned off once the sun stops shining on the photovoltaic cells.
One solution to regulate the variability of solar power plants is to store energy when there is too much time (in the day). This way, the stored power can be provided at other times, including serving periods of higher demand – usually later in the day with less sunlight around.
MoonwattA clean technology startup, founded in the Netherlands last September, is co-locating and optimizing battery-based energy storage systems with solar power plants to help them manage this variability. The team designed dedicated battery enclosure hardware, inverter power electronics connected to the grid and the software needed to integrate and manage storage systems.
The startup said its approach would enable solar power plants to increase revenue by selling more solar energy, including more attractive energy prices and reducing plant-level costs, as the design reciprocates some electrical infrastructure. The target solar power plant is the one who produces at least a few hundred kilowatts of energy – so basically, anything other than residential PV deployments.
It is worth noting that Moonwatt’s system is built around sodium ion batteries to use to store solar energy. This technology provides an attractive alternative to lithium ions, as production relies on cheaper (easy to source) raw materials, which helps reduce costs.
While sodium-ion batteries can have size and weight challenges owing to being lower density than lithium-ion cells — making certain applications challenging (such as mobility/EVs, where weight is an important consideration) — the technology has been gaining traction as a lower cost storage option for renewables where conditions are more favorable, given these are stationary installations at sites with plenty of space to install kit.
Get more juice from PV
Moonwatt’s pitch to solar power plants is that their energy storage system allows them to increase their capacity factor to 80%. They also suggest that the purchased plants will be able to double their internal rate of return (IRR).
“Basically, what we allow partners to do is double their returns,” Valentin Rota, co-founder and chief commercial officer, told TechCrunch. “So in AAA [credit-rating] Country, I would say average PV [photovoltaic] Assets already exist, assuming a return of 8% to 12% – IRR – we will make the asset reach around 20%. ”
The startup’s founding trio met with CEOs Zukui Hu and Cto Guillaume Mancini while developing battery technology for Tesla about a decade ago. Since then, they have continued to work together across different employers and various projects, including gaining experience in small, off-grid solar storage.
“We started to see the app first start with what we call a microgrid, so it’s usually a grid-resistant generator,” Rota said. “But, as the cost of the battery drops, the storage costs drop, in fact, these applications start to reach larger countries with larger grids, which is really powered by the basic speed of solar energy.”
The founder also worked with battery maker Freyr (renamed Ti Energy as Ti). Once they saw the cost move in the right direction, Rota said the spark of setting up Moonwatt (named after the vibrant game on the “Moon Rover”), and we think they could combine the knowledge of battery hardware and apply battery technology to power solar storage growth.
“We realized that the application – solar storage – was the backbone of the future world’s power grid, but there was no specialized product yet,” he said. “That’s what Moonwatt is about: it’s about making the first solar-powered battery storage product.”
As the volume of solar power produced worldwide continues to surge, startups are betting that the industry will begin looking for dedicated storage rather than using the “Cookie Cutter” product.
Moonwatt’s “big differentiator” includes using sodium ion battery technology – which he says provides better scalability than lithium ions, lower costs and carbon footprint.
Their storage system is also designed to use distributed architectures (rather than centralized), making it easier for plants to integrate as he tells. He also said the approach they took could increase efficiency and reduce dispatchable power costs, thanks to panels that bring the stored connection closer to the peak output.
“With these three features, our overall goal is to reduce the electricity costs of these dispatchable solar plants,” he added.
Seed funds step on gasoline
While it’s too early to have (only) months of business and its prototypes, Moonwatt has now closed its 8 million euro seed financing round (about $8.3 million in current exchange rates) to step onto gasoline and bring its storage technology to market – starting with a pilot installation planned somewhere in Europe this year. They then expect their first commercial deployment in 2027.
The Seed Round is co-led by Daphni and Lea Partners, from founders Future, AFI Ventures (Ventech) and Kima Ventures, as well as strategic business angels and clients.
Daphni’s partner Paul Bazin commented in a support statement that Moonwatt’s approach was a “breakthrough in the industry’s missing.”
“Renewable capacity growth has exceeded all expectations, but we are approaching a turning point that we cannot scale further without better energy storage,” he said. “Created by industry veterans, Moonwatt is solving this problem with differentiated storage products specially made for solar energy.”
“We are very nourishing to be Gigawatt-Hour’s ambition, which is a big player because we want to make an impact,” Rota also told us. “With the cost of scale. And we know that in this industry, it’s a bottom-line-driven business, so we have to be cost-competitive.”
Rota said the decision to focus on solar energy comes down to attractive economics and the widespread absorption of this renewable energy.
“Solar energy is interesting because its cost is the cost per megawatt-very competitive and becomes more competitive,” he noted. “But it’s also more common in solar energy. It’s already deployed in over 120 countries every year.”
Optimizing for solar energy alone means the startup can be fully focused on making design choices designed to help plants make the most of their assets, including when shrinking the cost of connecting energy to the grid.
“Looking forward, the way to reduce [solar energy] Cost is an overall balance by reducing plant costs. Therefore, you need to reduce the number of transformer cables, etc. The way you do this is that you blend solar and repository, not medium voltage levels, but at low voltage levels – actually next to each other. ” he suggested.
“By doing this, they share the same electrical infrastructure that can be connected to the grid. And if we expand the view to more like a country level, it’s also something we have to do to optimize the use of grid capacity. Because today, independent solar plants only use about 20% of their grid capacity, but when you add storage space behind the meter, you can really change the energy usage, allowing you to use this grid capacity more efficiently.”
The startup business at hand is also designed to help solar power plants transition from tariffs to “almost” to become energy traders with flexible assets, he added.
