Swedish WEC developer Ocean Harvesting Technologies AB and Finnish kinetic energy storage company Teraloop Oy, are collaborating to integrate Teraloops outer-rotor flywheel technology into InfinityWECs power take-off (PTO) system. A full-scale system design has been completed and the next step is the build and test of the InfinityWEC PTO in a half scale test rig. Both companies develop sustainable energy systems that enable more effective extraction of renewable energy and facilitate integration of renewable energy production into the grid.

InfinityWEC offers electricity production at a levelized cost of energy (LCoE) very competitive to offshore wind power. The novel PTO system also improves reliability and survivability of the device and provides a constant and predictable output power. Furthermore, an InfinityWEC array has virtually no visual impact and requires less than 1/10th of the areal footprint compared to offshore wind power.

Mikael Sidenmark, CEO at Ocean Harvesting:

“We identified Teraloop in our search for energy storage technology options for the InfinityWEC. Teraloop’s technology integrates perfectly with the InfinityWEC PTO system and has unique capabilities to manage the requirements for efficient PTO force control and smoothing, as well as 100 million charge/discharge cycles in a 20-year design life.”

Ian Denton, Chief Engineer at Teraloop:

The InfinityWEC concept is a step change that will allow wave-energy-conversion to provide a significant share of the renewable energy mix. For Teraloop, this is a unique opportunity to provide a solution where existing technology is unable to address the challenging performance requirements. We look forward to collaborating with Mikael and his team, toward our shared vision of fully-renewable generation of electricity”.

The 500 kW InfinityWEC is the first “smart” wave energy converter to use flywheel energy storage to provide advanced PTO force control in combination with a constant/time shifted output power. The principle of the technology originates from electrical vehicles where it is referred to as Kinetic Energy Recovery System (KERS). KERS applied in wave energy enables the PTO force to be optimized in every individual wave, providing the following advantages:

  • Increased power output by using phase control.
  • Improved reliability and survivability by controlling the buoy motion to avoid hard end stops and snap loads in large waves.
  • Reduced cost by limiting the maximum force, velocity, power and stroke-length in the PTO system.
  • Increased revenues by providing a constant, controllable and more predictable output power, and also ancillary services such as frequency regulation to help solve grid stability issues coming from the increasing share of renewables into the electrical system.
  • Benefits from model prediction, AI and machine learning techniques to optimize the PTO force.

The Teraloop flywheel is based on an outer-rotor design integrated with a permanent magnet motor/generator. The rotor is supported by a magnetic levitation system and electromagnetically stabilized to handle movements, in a similar way as magnetic high-speed trains. The novel Teraloop flywheel energy storage design offers a unique combination of high power, high energy and sufficient charge/discharge cycles to last for the 20-year design life of a wave energy converter. The outer-rotor design improves the energy-per-unit-mass beyond the capability of existing flywheel designs. This makes more effective use of materials and allows a more compact design.

For more information, please contact:

Mikael Sidenmark, CEO
+46 709 55 61 66
Ocean Harvesting Technologies AB

Philippe Pépin, COO
+358 46 847 2907
Teraloop Oy

About Ocean Harvesting Technologies

Ocean Harvesting Technologies AB was founded in 2007 in Karlskrona, Sweden, to develop wave power technology. R&D has been focused on energy storage integration in the power take-off, to improve the power capture performance and smoothen power output. In 2017, OHT realized the opportunity of using a Kinetic Energy Recovery System from electrical vehicles to accomplish this, which led to the development of the novel InfinityWEC Wave Energy Converter.

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About Teraloop
Teraloop Oy was founded in 2014 in Helsinki, Finland, and develops technology for large-scale kinetic energy storage used in commercial and industrial, grid and utility applications. Teraloop’s patented core technology has been applied to a kinetic energy storage system, which builds on existing proven and deployed technologies. The result is an innovative system for grid-scale storage with a minimized visual and environmental footprint.

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