Our technology

Scalability

In traditional flywheel the rotor is physically attached to a central hub and radial stress intensifies as the rotor diameter increases, thus limiting the rotor size.

Our system uses a hubless rotor design to minimize the radial stress, thus enabling superior scalability.

Effectiveness

Our system can deliver energy storage using a minimal amount of area, even 1 MW/m2. Price per kW and OPEX are low, leading to a low total cost of ownership.

We are currently developing novel flexible magnetically loaded composite designed to allow increased specific energy of the rotor up to 100 Wh / kg.

Sustainability

We are working on solutions to further minimise our environmental impact by using more sustainable options for our rotor materials, such as recyclable resins and carbon fiber obtained from recycled sources or residual bioresources.

Using our solution provides secondary positive impacts on sustainability, such as better feasibility of renewable energy sources, decreased need for critical raw materials through battery lifetime extension as well as support for sustainable livelihoods through access to affordable and clean energy.

Carbon fiber

Materials

Our flywheel rotor is made of extremely strong carbon fiber reinforced composite to maximize the rotational speed and energy storage capacity of the rotor. We are currently exploring more sustainable and cost-efficient alternatives to traditional carbon fiber, preferably sourced from bio-based or recycled raw materials. In particular, we expect to see a decrease in the cost and carbon footprint of carbon fiber production by manufacturing it from bio-based residues, such as agricultural waste. Furthermore, we aim to contribute to mitigating the accumulation of composite waste by using carbon fiber recycled from other products, such as discarded wind turbines.

Magnetically loaded composites

Materials

The high rotational speed of the rotor imposes strict demands for the material properties of the magnetic composite used in the electromagnetic stabilization system of the flywheel. In order to further increase the rotational speed and thus the energy storage capacity of the flywheel, we have to improve mechanical robustness and fatigue resistance of the composite while maintaining sufficient magnetic performance. We are currently tackling these challenges as a part of the international SoftCompEl-consortium, founded to develop next generation high-performance magnetic composites. We will achieve these goals with careful selection of resins and magnetic particles, and by controlling their interfacial interactions via suitable surface modification.

We aim to more than double the current specific energy of the rotor to 100 Wh/kg, surpassing current flywheel and supercapacitor technologies. These advances will allow our flywheels to replace Li-Ion batteries for selected applications and reduce dependency on critical materials such as lithium and cobalt.

Epoxy resins

Materials

The sustainability of the rotor is largely determined by the properties of the epoxy resin, where the carbon fiber and magnetic particles are embedded. To reduce the environmental footprint of our products, we aim to transition to epoxy resins that feature reversible curing mechanisms to facilitate reprocessing or recycling of the rotor materials. We are also investigating resins that are based on renewable, non-food chain biomaterials. Both these approaches can decrease the use of petroleum-based and toxic substances, and reduce the greenhouse gas emissions.