INFINITY Project will develop lifetime-aware Model Predictive Control (MPC) to be tested on InfinityWECs power take-off in an HIL test rig at VGA in Italy.

Optimizing power take-off systems and control algorithms for wave energy converters is essential to reduce the use of materials per MW installed capacity and lower the levelized cost of energy (LCOE). The INFINITY Project delivers the next generation PTO and control system, taking advantage of learnings and test methods from both the IMPACT and the VALID H2020 projects.

The project is co-ordinated by RISE Research Institute of Sweden, and will run for three years starting in December 2024. New high-fidelity simulation models will be developed by COER at Maynooth University to facilitate the development of a new non-linear moment-based and lifetime-aware MPC algorithm by Politecnico Di Torino. A 1:3 scale InfinityWEC power take-off will be built, and tested with the new control algorithm in VGAs HIL test-rig in Italy. The tests will demonstrate real-time performance of the new MPC, and verify the improved lifetime of the power take-off, leading to reduced CAPEX/OPEX relative to the annual energy production. The project aims for 20% LCOE reduction.

“The INFINITY project will pave the way for model predictive control on real-time control systems, which will significantly reduce LCOE for wave energy,” says Mikael Sidenmark, CEO of Ocean Harvesting. “Our InfinityWEC is designed specifically to benefit from advanced control algorithms in order to maximize energy production, and also control motion and loads for reliable operation and long life.” he continues.

The InfinityWEC power take-off uses a combination of highly efficient direct drive ball screw actuators and a hydrostatic pre-tensioning system to provide instant force control capabilities. The buoy is made of ultra-high performance concrete (UHPC) in a honeycomb structure, leading to very low weight. The combination of high performance and use of low-cost and circular materials results in exceptional resource efficiency with low weight, cost and CO₂ per MW/MWh.  

Ocean Harvesting is currently developing generation 6 of its wave energy converter InfinityWEC in close collaboration with ball screw manufacturer NSK. A ball screw is a very good actuator providing a high ratio between linear motion and rotation to the generator, high efficiency, low weight and long life. However, ball screws are sensitive to the side forces and bending moments in the PTO caused by the surge motion of the buoy and high speeds that may occur in large waves. This challenge in the design of the PTO has been solved with a new linear guide system and increased control force.

Ocean Harvesting is now implementing and evaluating a moment-based MPC (model predictive control) in InfinityWECs simulation model, showing significant improvement in energy output and computation time. Due to the increased control force, the velocity and stroke in the system can now be controlled and limited by the MPC, simplifying the design and making the system run more smoothly. The buoy can be pulled down and the PTO locked in contracted state to avoid the highest loads in storm conditions.

“The combination of ball screw actuators with our hydrostatic pre-tension system is a very efficient solution to provide the control force needed in the PTO,” says Mikael Sidenmark, CEO at Ocean Harvesting. “The solution benefits from the use of advanced model predictive control algorithms to optimize the force applied to the buoy in every given moment, resulting in both outstanding annual energy production and the ability to constrain the velocity and stroke in the PTO.”

Mikael Sidenmark continues: “The new design provides very good operating conditions for the ball screws. We have increased from two to four ball screws to achieve 25-year lifetime, thereby also increasing the peak force capacity from 1 to 2 MN, which in combination with the hydrostatic pre-tension provides higher control force than the buoyancy of the buoy.”

Focus in 2024 and early 2025 is the completion of the full-scale system design for InfinityWEC generation 6, implementation of the moment-based MPC algorithm in the control system, and preparation for the 1:3 scale sea trial project planned for 2025-2026.For these activities, Ocean Harvesting is raising 450,000 Euro in a financing round where new investors are invited.

About wave power and Ocean Harvesting:

Wave power is a huge untapped resource of renewable energy that provides more consistent electricity production compared to wind and solar power, and which occurs at different times. This increases the value of produced electricity and reduces the need for energy storage to balance the electrical grid.

Ocean Harvesting has developed the 500kW wave energy converter InfinityWEC since 2017. The main advantages are (i) high annual energy production provided with a breakthrough power take-off (PTO) and (ii) the use of circular materials with low cost and low CO2 footprint. The result is 6 times lower cost of materials and 6 times lower CO2 emissions from the materials used per MW/MWh compared to floating wind power. The technology is developed in collaboration with industrial partners and in joint industry projects.

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Ocean Harvesting Technologies AB has since 2017 been developing the wave energy converter InfinityWEC. During 2023 and early 2024, focus has been on the ball screw actuation system in the power take-off and refining simulation models for generation 6 of the technology. Full-scale system design of InfinityWEC will continue in 2024, planned to be followed by a 1:3 scale sea trial project in 2025-2026.

Ocean waves are a vast resource of renewable energy and wave power can produce electricity more consistently and at different times than wind- and solar power. This increases the value of produced electricity and reduces the energy storage needed to balance the grid or stand-alone facilities.

InfinityWEC is a novel wave energy converter with a breakthrough power take-off, providing very cost-efficient electricity production by maximizing the energy output from every individual wave, and producing up to 500 kW continuous power output. The energy production cost (LCOE) is estimated to be very competitive at 100 Euro/MWh already at 100 MW deployed capacity and <35 Euro/MW at GW scale deployment.

“The ball screw actuators in the power take-off in combination with our hydrostatic pre-tension system is a very efficient solution,” says Mikael Sidenmark, CEO Ocean Harvesting. “It benefits from the use of advanced model predictive control algorithms to optimize the force applied to the buoy in every given moment, which results in both outstanding annual energy production and the ability to control and reduce buoy motions and loads in the system.”

InfinityWEC is based on circularity by design principles and achieves very high material efficiency and low environmental impact through the combination of high energy output and use of low-cost and low-carbon materials. InfinityWEC is engineered for large-scale production and effective transports and logistics enabling efficient deployment of wave farms.

Mikael Sidenmark continues: “Our focus in 2024 is the implementation of a new enhanced model predictive control (MPC) algorithm in the control system, and completion of the full-scale system design. We will also bring forward our buoy technology as part of the on-going EU-financed WECHull+ project. Preparations will continue for the 1:3 scale sea trial project planned for 2025-2026, for which a 2 million Euro grant has been approved by the Swedish Energy Agency.”

For these 2024 activities, new investors are invited to a 500,000 Euro financing round, divided into 120,000 Euro for the period April–June 2024 and 380,000 Euro for the remainder of the year.

For more information on Ocean Harvesting and this Investment opportunity, please contact:

CEO Mikael Sidenmark, +46 709 55 61 66
mikael.sidenmark@oceanharvesting.com

Ocean Harvesting and ball screw manufacturer NSK have completed the design of the ball screw actuation system for InfinityWEC generation 6, and Ocean Harvesting is now raising 500 000 EUR for 2024 activities and preparing for a 1:3 scale sea trial project in 2025-2026.

Wave energy is a vast resource of renewable energy that can produce electricity more consistently and at different times than wind and solar. This increases the value of produced electricity and reduces the energy storage needed to balance the grid. InfinityWEC is a novel wave energy converter with a breakthrough power take-off and control system, providing an outstanding annual energy production by maximizing the energy output from every individual wave. The technology also has very high material efficiency using circular materials with low-cost and low-CO2 emissions, leading to low cost of electricity and low environmental impact.

During 2023 and early 2024, Ocean Harvesting has focused on developing the ball screw actuation system in the generation 6 power take-off of the InfinityWEC wave energy converter. Simulation models have also been updated and extreme and fatigue loads have been analysed.

Ball screws are very efficient at converting linear motion with high force into a high-speed rotation suitable for direct drive generators/motors, to provide instant force control which is key to InfinityWEC’s exceptional energy production performance. InfinityWEC is a novel and challenging application with regards to extreme and fatigue loads, and much work has been done to improve operating conditions for the ball screws. Furthermore, the number of ball screws in the PTO have been increased from two to four to achieve 25-year lifetime, which at the same time increases the available force from the ball screws from 1 to 2 MN. This in turn makes it possible to control the motion of the buoy and the velocity in the power take-off, which is important for the durability of the ball screws and to reduce forces during end stops.

“Ball screw actuators in combination with our hydrostatic pre-tension system is a very efficient solution,” says Mikael Sidenmark, CEO Ocean Harvesting, “which benefits from advanced predictive control algorithms to optimize the force applied to the buoy in every given moment, resulting in both outstanding annual energy production and that motion and loads can be controlled and reduced.”

Eduardo Rodriguez, Director NSK Europe, says: “We see a clear synergy between high efficiency products and limitless energy sources like waves, as well as many opportunities for success and development in this area. We’ve established a longstanding partnership with Ocean Harvesting, and know that together we can develop successful prototypes and deliver very promising results. NSK is a leading manufacturer of ball screws in the high-load sector, and we expect that developments like this will open up a large field of activity for us going forward.”

Mikael Sidenmark continues: “Focus in 2024 is to perform structural analysis, implement model predictive control (MPC), and to complete the full-scale system design. We will also prepare for a 1:3 scale sea trial project planned for 2025-2026, as well as bring forward our buoy technology as part of the on-going EU-financed WECHull+ project. For these activities in 2024, we are now raising 500,000 Euro, preliminarily divided into a 120,000 Euro financing for the period March – June 2024 and 380,000 Euro for the remainder of the year.”

For more information, contact:
CEO Mikael Sidenmark, +46 709 55 61 66
mikael.sidenmark@oceanharvesting.com

About NSK Europe

NSK Europe Ltd. is the European organisation of the Tokyo-based bearing manufacturer NSK, which was founded in Japan in 1916 and today employs nearly 29,882 people in its worldwide operations. The products and solutions provided by the industrial and automotive supplier can be found wherever things move. In addition to nearly all types of rolling bearings, the company’s portfolio includes housed bearings, linear technology, wheel bearing units, transmission and engine. The company is oriented to perfection in all of its business activities. Its aim is quality leadership in its industry, which it strives for through a continuous process of improvement, excellent product development, optimised production processes and customer-oriented service processes. In fiscal year 2022, the more than 4,030 employees of NSK Europe Ltd. generated sales of over € 893 million.

www.nskeurope.com

About Ocean Harvesting and InfinityWEC

Ocean Harvesting is a privately held company based in Karlskrona and Gothenburg, Sweden. The development of the wave energy converter InfinityWEC was started in 2017.

InfinityWEC is a highly competitive and resource efficient technology with an advanced power take-off system using a combination of ball screw actuators and a hydrostatic pre-tension system to provide instant control if the force applied on the buoy. The solution benefits from the high performance achieved with model predictive control, resulting in outstanding annual energy production at the same time as motion and loads can be controlled and limited.

InfinityWEC is engineered for large-scale production and effective logistics with a power take-off that can be shipped with standard container transportation on road, railway and sea, and with a prime mover (buoy) made as a honeycomb structure with thin walls of high-performance concrete, that is casted with locally sourced materials at the installation site. A special high strength and sustainable concrete mix has been developed in collaboration with RISE Research Institutes of Sweden, enabling a prime mover with equivalent weight to a conventional steel hull, but at a fraction of the cost and manufacturing time.

Compared to floating wind power, InfinityWEC uses only about half of the total amount of material and 90% of the used materials is low cost and low carbon concrete and ballast compared to almost only steel in a wind turbine, resulting in 6x lower cost and 6x lower CO2 footprint from materials used per MW installed capacity.

240307 OHT news – Update on InfinityWEC ball screw actuation system – en

240307 OHT news – Update on InfinityWEC ball screw actuation system – sv

The WECHULL+ project, co-ordinated by RISE Research Institutes of Sweden, has received a 2.5 MEUR grant from the EU Clean Energy Transition Partnership (CETP) program. The project will develop and test new floating structures of high-performance concrete, reducing cost and CO₂ footprint, as well as improving circularity and reliability, in the offshore renewable energy sector. It is a 3-year project, starting in December 2023, implemented by a consortium of research organizations and companies from five European countries (RISE, Delft University of Technology, Carnegie Clean Energy, Ocean Harvesting Technologies, Gdansk University of Technology, SolarDuck, PLOCAN and Pekabex).

Concrete structures are low cost, resistant to the marine environment, and are easy and fast to manufacture on-site (casting), in comparison to manufacturing of traditional steel structures. Concrete is the most used material in the world after water and has a mature value chain enabling local production worldwide. The solutions developed in the WECHULL+ project regarding material, modelling and design will be applicable for floating structures in ocean renewables and other areas.

WECHULL+ is based on the excellent results and proof-of-concept from a previous project (WECHULL), where a new, highly flowable high-performance concrete mix was developed for Ocean Harvesting’s patented thin-walled honeycomb buoy. The solution enables large scale production on site and results in a buoy with a weight similar to a conventional steel hull, but at 4x lower cost, 3x lower CO₂ footprint and 10x faster to manufacture.

“Reducing the use of resources and the environmental impact are critical in the energy transition,” says Mikael Sidenmark, CEO Ocean Harvesting Technology. “We are very pleased that our honeycomb design for floating structures will also be tested by other ocean energy developers in sea trials, and we look forward to this collaboration.”

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Download press release in Swedish

A comparison of the material efficiency between InfinityWEC Wave Power and offshore floating Wind Power.

InfinityWEC is a 500 kW wave energy converter with advanced control technology to maximize energy output from every wave, designed to use mainly low cost and low carbon materials. InfinityWEC is suitable for the same areas as floating wind power, in 80 – 200m water depth. A comparison of the material efficiency shows that InfinityWECs cost and CO2 footprint per MW installed capacity are 7x lower compared to floating wind power.

The Levelized Cost of Energy (LCOE) is the standard metric for renewable energy technologies. LCOE gives the complete picture for an installation and is derived from cost of equipment (CAPEX), operation & maintenance (OPEX) and annual energy production (AEP). Early-stage technologies must use assumptions and estimations of unknowns and learning curves, to compare LCOE with mature and established technologies such as offshore wind power, which already has several GW of power installed.

The material efficiency is an important complement to the LCOE to estimate the economic potential of renewable energy technologies. This is a straightforward metric to benchmark emerging technologies versus mature and established technologies. It assumes that cost per ton for each material is the same for all technologies, as well as the CO2 equivalent per ton. This makes it possible to calculate and compare the total cost and CO2 emissions of materials used per MW installed capacity.

Mikael Sidenmark, CEO, says: “The reason for the exceptional techno-economic potential of InfinityWEC is the combination of firstly using mainly low-cost materials such as concrete in the buoy and high-density ballast in the gravity base anchor, and secondly, the design of the power take-off with very high annual energy production per ton of steel.”

Material Efficiency – InfinityWEC vs Floating Wind Power

Material efficiency is derived from the amount in tons of each type of material used per MW installed capacity. These weights are then combined with the corresponding price and CO2 footprint per ton for each material.

InfinityWEC targets the same ocean areas as floating wind power, with installation depth of 80 – 200 m, and for this reason Hywind Scotland is used in this comparison. Hywind Scotland consists of 6 MW wind turbines and in this example it is compared to 6 MW clusters of InfinityWEC. Power export characteristics from an InfinityWEC cluster match the grid connection from a wind turbine. The comparison is therefore limited to the clusters / wind turbines since similar power export infrastructure can be used.

Ocean Harvesting is raising 400 000 EUR in financing for activities in 2023 to enhance the control system and optimize the design of InfinityWEC wave energy converter, leading up to a sea trial project of InfinityWEC in scale 1:3, planned for the period Jan2024 – Dec2025. This project has already been awarded a 2 MEUR grant financing from the Swedish Energy Agency, with an additional 3 MEUR in financing to be raised later in the year.
 
InfinityWEC is a breakthrough wave power technology with very high annual energy production per size of the device. This is achieved with an ingenious power take-off solution to provide instant force control with high efficiency and low cost, and with a buoy made in a honeycomb structure with a specially designed low carbon high performance concrete. The solution offers exceptional material efficiency and will be very competitive. 
 
The technology is unique in its capability to host and benefit from advanced predictive control algorithms and OHT is now implementing recent advancements from leading researchers in the field, showing very promising results in terms of increasing the energy output, reducing loads and being fast enough for a real time control system. We will demonstrate the performance of model-based predictive control algorithms in real sea testing. Read more
 
Please contact CEO Mikael Sidenmark for more information and to receive the investment presentation.

The InfinityWEC wave energy converter has been upgraded with an innovative solution which uses hydrostatic pressure to provide a constant pre-tension force in the power take-off (PTO), reducing size, weight, complexity, and ultimately cost of electricity production (LCoE).

In the upgraded InfinityWEC design, the PTO hull is split into two halves, with the top half moving up and down with the buoy, while the bottom half is fixed to the anchor. Similar solutions have been used by pressure-modulating wave energy converters, to extract energy from the variation in pressure below waves, close to the surface. InfinityWEC however, is a point-absorbing wave energy converter, with a buoy on the surface driving the PTO positioned close to the seabed. At 70 m depth, the high pressure of the water provides a 100-ton pre-tension force with only a 1.6 m diameter PTO hull. A patent application has been filed for the innovation.

“The new pre-tension solution is a further improvement of the InfinityWEC wave energy converter, reducing the weight of the PTO by approximately 40%,” says CEO Mikael Sidenmark. “We take advantage of the water pressure outside the PTO to generate the constant pre-tension force, which in combination with ball screw actuators provides instant force control with very high efficiency. This enables wave-by-wave tuned force control, improving the annual energy production by up to 30% compared to sea-state tuned control.”

Ocean Harvesting is preparing for sea trials of InfinityWEC at scale 1:3, to be performed off the west coast of Sweden. The sea trial project, to validate the performance in a real sea environment, will be conducted between February 2023 – June 2025. Results will be used to further develop and improve the full-scale system with regards to energy yield, system efficiency, availability, and ultimately affordability.

On 14 November, Ocean Harvesting was awarded a 2 MEUR grant from the Swedish Energy Agency for the project. To complete the project financing, the Company is now raising 3 MEUR in equity investment at a pre-money valuation of 7 MEUR.

The grant is for the project ”InfinityWEC wave energy converter – Validation through sea trials at scale 1:3”, to be performed off the west coast of Sweden.

The sea trials will validate the performance in real sea environment and the results will be used to further develop and improve the full-scale system with regards to energy yield, system efficiency, availability, and ultimately affordability. The project is implemented in cooperation with RISE Research Institutes of Sweden and will be executed during the period March 2023 – June 2025. Ocean Harvesting follows the staged validation framework for ocean energy technologies set out by Ocean Energy Systems (IEA).

Offshore oil & gas platforms require constant power supply and decarbonization of this power is a high priority. A case study with Lundin Energy Norway has shown that wave power is highly competitive with offshore wind power, both in terms of levelized cost of energy and providing a more stable power supply that requires only half as much power balancing.

To assess the sizing and power balancing requirements of the oil & gas platform, a one-year time series with sea state data was analysed. A design for a 100 MW wave farm was developed for on- and off-grid installations. The output power profile was compared with the output power profile from an equivalent wind farm and wind data for the same place and time period. The more consistent nature of waves was evident and wave power provided a significantly more stable power production.

An off-grid wind farm installation requires ⁓50% more energy storage compared to wave power, both in terms of power and energy capacity, and twice as much energy pass through the storage to balance the output. The cost for balancing the produced power is therefore considerably lower with wave power, by reducing both the cost of the energy storage system and the loss of produced electricity occurring when the energy storage is used.

Hydrogen was identified as the most viable solution for long-term seasonal balancing in an off-grid installation, due to the large quantities of storage required. It can also be noted that using depleted gas fields to provide hydrogen storage is considered an interesting opportunity for oil & gas companies to continue generating value from such assets.

“In addition to the very promising findings of this case study, it has also made it possible for Ocean Harvesting to develop a comprehensive array and system design, a handling plan, and a life cycle cost assessment for a 100 MW wave farm, all of which will be very valuable going forward towards sea trials and commercialization,” says Mikael Sidenmark, CEO.

InfinityWEC is based on the following Design Principles, to achieve high performance, low cost and to be prepared for high volume production and roll-out

Ocean Harvesting has filed a new patent application for an improved pre-tensioning system in the power take-off, replacing customized components in the previous design with standard components. This is the sixth patent family protecting the InfinityWEC technology and its novel power take-off and concrete buoy.

Next step is scale 1:3 sea trial for which we are now raising 3 MEUR in private financing, read more.

To finance sea trials with wave energy converter InfinityWEC at scale 1:3, Ocean Harvesting is raising 3 MEUR in equity investment at a pre-money valuation of 7 MEUR. This investment will be combined with public financing for the project. The sea trials are planned to be completed by the end of 2024, after which commercialization of the technology will be initiated with sea trials of full-scale systems.

A transition to 100% renewable energy is necessary to mitigate climate change. Solar and wind energy are driving the transition but will not be sufficient given the enormity of the task and geographical, space and other constraints. Much more renewable energy will be needed. Wave energy is a vast, unexploited resource for renewable electricity generation. It can furthermore add substantial value by reducing variations in electrical grids with a high degree of renewables, and thereby reduce the amount of energy storage needed to balance electricity supply and demand.

InfinityWEC can unlock the potential of wave power through its advanced power take-off and control system, which tunes to every individual wave to produce electricity efficiently in all sea states. Furthermore, a unique end-stop function ensures both survival and continuous, reliable power production even in the harshest wave conditions. The novel buoy design is made with high strength concrete, with weight similar to a conventional steel hull, but at a quarter of the cost, a third of the CO₂ footprint, and one tenth of the manufacturing time. In all, the exceptional performance and reliability, using proven subsystems and a modular design, make InfinityWEC a highly competitive solution for the future global energy market.

Ocean Harvesting is preparing for sea trials of InfinityWEC at scale 1:3 to be performed off the west coast of Sweden. The sea trials will validate the performance in real sea environment and the results will be used to further develop and improve the full-scale system with regards to energy yield, system efficiency, availability, and ultimately affordability.

Ocean Harvesting follows the staged validation framework for ocean energy technologies set out by Ocean Energy Systems (IEA). InfinityWEC has with simulations and physical tests in a test rig in scale 1:10 and in a wave tank been successfully verified with regards to critical functionality of the power take-off and control system, sea-keeping and survival functions in extreme conditions, and the power production performance. The technology is on track towards a competitive cost of energy at 100 EUR / MWh already at 100 MW installed capacity, and < 35 EUR / MWh at large scale deployment, with the added value of reducing the need for energy storage to balance supply and demand of electricity.

The market for InfinityWEC ranges from utility-scale wave farms to off-grid applications such as oil & gas platforms, island communities, green hydrogen production and aquaculture.

Karlskrona/Gothenburg, Sweden; 6 May, 2022

Ocean Harvesting is developing a novel concrete hull for the prime mover (buoy) of the InfinityWEC wave energy converter, using high strength concrete with low environmental footprint and excellent durability. The solution allows for large scale production and results in a buoy with a weight similar to a conventional steel hull, but at 1/4 of the cost and 1/3 of the CO2 footprint.

Highly flowable concrete is poured into a mould with void fillers, forming the concrete shell and the internal honeycomb structure, one of the strongest structures in nature. Most of the raw materials will be sourced locally at the installation site, where the buoy is cast in a process common in civil engineering. The buoy will be towed or shipped to the installation site and linked to the InfinityWEC PTO system with a mooring rope, which enables quick and diverless attachment and detachment of the buoy from the PTO system during installation and maintenance operations.

The RISE (Research Institutes of Sweden) department for Infrastructure and Concrete Technology has developed a unique high-performance concrete mix for the buoy, as part of the joint industry project WECHull. To facilitate a thin-walled, lightweight structure and easy, rapid manufacturing, alternative reinforcement measures were investigated, evaluating the use of fibres of different types (carbon, aramid, glass, steel and biomass), as well as polymer reinforcement with carbon-textile grids. By using recycled aggregates and replacing more than 50% of the cement content, InfinityWEC’s buoy is aligned with the European Circular Economy Action Plan.

The next development stage for Ocean Harvesting is a sea trial of InfinityWEC at scale 1:3, a project planned to start in November 2022. The sea trial will demonstrate the InfinityWEC technology and its control system, and their performance in the real sea environment. This is a critical step towards the final validation stage of the system at full scale and the commercialization of the technology.

Karlskrona/Gothenburg, Sweden; 5 May, 2022

Ocean Harvesting has successfully completed the testing of a prototype in scale 1:10 of the power take-off (PTO) and the control system for the wave energy converter InfinityWEC. The design, build and testing in the rig was part of a project co-financed by the Swedish Energy Agency.

To obtain a realistic load on the machinery, a scaled hydrodynamic model of a full-size wave energy converter (WEC) was used in combination with the physical PTO prototype and a real-time control system in a hardware-in-the-loop (HIL) configuration. A control system has been developed for both the PTO and the HIL rig, which in combination with the physical representation of the PTO, with all essential functionality included, demonstrates that the technology works as intended.

The project validated that all critical parts of the PTO could be built with standard components. The full-scale design aims to use standard components with high availability from suppliers, to minimize risks, shorten development time and reduce the costs of the final product.

The control system developed for the project is based on a modern software architecture using OOP (object-oriented programming) and TDD (test-driven development). It is based on Beckhoff PLCs and TwinCAT software, which is a suitable and cost-effective solution both for HIL testing and for large-scale offshore deployment of wave energy converters in wave farms. The developed software will be transferred to and further developed in the full-scale development phases of InfinityWEC.

The test rig will have continued use as a development platform to evaluate advanced reactive control strategies and design principles, to further refine InfinityWEC’s capability to extract maximum power from every individual wave.

The next development stage for Ocean Harvesting is a sea trial of InfinityWEC at scale 1:3, a project planned to start in November 2022. The sea trial will demonstrate the InfinityWEC technology, control system and its performance in a real sea environment, a critical step towards the validation stage of the system at full scale and commercialization of the technology.

Ocean Harvesting Technologies (OHT) has commissioned a Hardware in the Loop (HIL) test rig at scale 1:10 to validate the InfinityWEC power take-off (PTO) with instant force control capabilities.

The test rig simulates the buoy motion with force feedback from the PTO system, and will be used to validate the complete functionality of the PTO and control system as in a complete WEC for real sea conditions. The functionality includes (i) instant force control capability in combination with efficiency and constraint-aware predictive control, amplifying energy capture, and (ii) a soft two-stage end stop, holding the buoy submerged through the crest of large waves to ensure both survival and continued, reliable power production even in the harshest conditions. The test rig will later be used as a platform to develop and evaluate AI-based control strategies and design principles, to further refine InfinityWEC’s capability to capture maximum power from each wave. The project is co-financed by the Swedish Energy Agency and will be completed by February 2022.

The developed control system will be used in the sea trial of a complete InfinityWEC system at scale 1:3, to take place on the Swedish west coast. The sea trial project is planned to start in 2022 and key suppliers are Sigma Energy & Marine, Acumo/NSK, and Beckhoff, among others. RISE Research Institutes of Sweden is partnering in the project and will be responsible for validation of the integrity of the hull that includes sustainable high performance concrete and biofouling as outcomes in the research project WEChull, financed by the Swedish Energy Agency.  

The sea trial in scale 1:3 will demonstrate that InfinityWEC is on track towards LCoE 100 EUR / MWh at 100 MW installed capacity and < 35 EUR / MWh at 5 GW installed capacity. System performance will be tested in real sea conditions and results will be used to validate and calibrate the simulation tools to predict energy yield, ownership cost, affordability, availability and process efficiency. The commercial-scale single device demonstration is planned to start in 2024, to be followed by array installations on commercial terms. The road map to commercialization follows the staged development process recommended in the Ocean Energy Systems (OES) framework, a technology collaboration program by the International Energy Agency (IEA).

OHT is, furthermore, performing a feasibility study on how a wave farm installation could provide electricity to one of Lundin Energy Norway’s oil & gas platforms. The study includes sizing and specification of the wave farm, energy storage, handling procedures and a life cycle cost assessment. OHT also participates in three joint industry collaborative projects led by RISE: WECHull (hull materials), Seasnake (dynamic power cables) and NextWave2 (sensor technology and algorithms for wave prediction).

OHTs technology is protected by five patent families filed since 2017, covering all vital aspects of the power take-off and control system, the buoy design and general arrangements.