Unlock the power of ocean waves

CalWave, a California, US-based developer of clean energy technologies, is working to unlock the power of the world’s oceans. The company is tapping into wave energy, the largest unused renewable resource and the third-largest after wind and solar, to support increasing global energy demands while decarbonising the industry through proprietary innovation.

The concept of using man-made devices to convert the kinetic and potential energy of ocean waves into electricity is nothing new. In fact, such innovations have appeared around the world dating back as early as 1799. However, fundamental challenges associated with efficiency and cost have long-held the industry back from achieving the same level of success as others in the energy space. Now, CalWave is proposing a feasible solution that addresses these key technical and financial barriers to provide clean, reliable, and affordable electricity to coastal communities worldwide.

Harnessing wave energy for power

CalWave’s xWave™ wave energy converter (WEC) device is built on the game-changing industry advancements in which the company was awarded for through the US Department of Energy’s Wave Energy Prize. No other wave energy technology has high efficiency and wave load mitigation united in one architecture. The xWave achieves high efficiency by operating fully autonomously and fully submerged which allows for protection from aggressive swells and storms, while also permitting energy capture from multiple degrees of freedom. “From a technical standpoint, what makes our device special is that we have integrated a novel wave load mechanism into the design similar to pitch and yaw control in wind energy,” stated Thomas Boerner, CalWave’s CTO. “Contrary to a set as-is geometry once the device is manufactured, we can actively change the geometry of the wave absorber body to not only operate efficiently in small waves – but also to continue operation in severe sea states encompassing very large waves.” These landmark features enable for high performance at lowest cost, which should lead to affordable energy prices once available to the market.

Marcus Lehmann, CEO and Co-Founder, Thomas Boerner, CTO and Co-Founder, and Julie Mai, Head of Communications, CalWave Power Technologies, USA,

highlight how ocean-based solutions are creating ripples as the world enters the greatest energy transition period in modern history.

Additionally, the xWave encapsulates other critical aspects that bode well with the needs of varied end users. Scalable in both design and functionality, energy farms that utilise the technology can supply coastal communities with anywhere from 5 MW to over 500 MW of local power. Further, the xWave achieves a minimum 40% capacity factor alone. Studies show that when co-located with offshore wind, over 80% capacity factor can potentially be reached. The device is projected to be able to withstand over 20 years of use in open-ocean and has been designed to survive 100-year storm events. With operation and maintenance processes occurring on the surface via hot-swap capabilities, incurred costs are also predicted to be lower than that of offshore wind. The technology has also been deemed to have an acceptable environmental impact according to the latest State of the Science report.

Figure 1. CalWave’s x1™ wave energy converter pilot unit was manufactured in-house in Alameda, California, US, with final assembly occurring onsite in San Diego, California.

Figure 2. CalWave’s x1 pilot unit during in-water testing prior to deployment.

Figure 3. CalWave successfully commissioned the x1 unit in California’s first long-term, open-ocean wave energy pilot in September 2021.

Testing in California and the US

In September 2021, CalWave successfully deployed an xWave pilot unit off the Scripps Institute of Oceanography research pier in San Diego, California. For the next six months, the x1™ WEC device, a scaled representation of CalWave’s x100™ architecture, will transform the motion of ocean waves into electricity before being transported back to the shore via an umbilical cable. This x1 device, as it is named, is securely anchored approximately 1800 ft from shore at a depth of 30 m. Before hitting the water, the x1 device was designed and manufactured in-house at CalWave’s warehouse space in Alameda, California. After the device arrived at the marina in San Diego, the CalWave team completed the final assembly before the first in-water test and deployment to site.

This event marks California’s first at-sea, long-duration wave energy pilot operating fully submerged. The x1 is currently being tested with the goal of validating the performance and reliability of CalWave’s system in open-ocean. For this trial, CalWave is also collaborating with Pacific Northwest National Laboratory & Integral Consulting, Inc. to monitor marine ecosystem acceptability of the WEC using three different tools: a noise spotter buoy, a drifting hydrophone, and three longterm, bottom-mounted hydrophones. So far, the global State of the Science report has not raised any red flags for marine renewables, but continued monitoring is needed.

Following the San Diego pilot, CalWave plans to prepare for deployment of the x100 unit, ranking 100 kW of power, at PacWave – the first federally-approved, commercial scale, utility grid connected wave energy site in the US, expected to start operating in 2023.

Scaling wave energy solutions to meet global needs

Looking forward, growing bodies of research project that wave energy has the potential to satisfy 20 - 30% of global energy demand. The US Department of Energy alone reports that wave power has the technical feasible resource potential to meet 30% of the US’ electricity demand, equalling US$120 billion in the total addressable market – yet, it is completely underutilised at the moment.

CalWave currently views isolated coastal and island communities as the greatest potential benefactors of wave energy development. Islands communities – some of the most adversely affected by the changing planet and roughly 11% of the global population – remain largely dependent on fossil fuel. CalWave aims to power microgrids on islands and in other isolated areas with its x100, 100 kW device. In addition, the x100

Figure 4. CalWave’s x1 pilot unit was deployed approximately 1800 ft from the Scripps Institution of Oceanography research pier in California.

can be utilised for powering data centres, eco-resorts, and military bases.

Similar to wind turbines, the xWave architecture is scalable in size. CalWave plans to offer a utility scale version in the coming years called the x800™, an 800 kW model. The x800 device has the capacity to support standalone wave farms operating fully submerged. This offers great benefits especially in areas where offshore wind is facing obstacles due to visual impact. Next to standalone farms, the x800 can also be co-located with offshore wind farms utilising the same and existing electrical export infrastructure and grid connection as well as other synergies such as offshore installation and maintenance.

Powering the blue economy

Now as the US Department of Energy’s Water Power Technologies Office works towards understanding the power requirements of emerging coastal and maritime markets, advancing technologies that could integrate marine energy to relieve power constraints, and enabling sustainable growth of the blue economy through its Powering the Blue Economy™ initiative, CalWave has an additional opportunity to make a significant contribution.

Based on the x1 technology currently being tested, CalWave is offering a solution to enable the Ocean Internet of Things by rolling out the production of the xNode™ series in 2022. xNode devices, which are uncabled and can be moored at any depth, utilise the xWave’s generator drivetrain and proprietary SCADA platform to provide offshore power and data as a service. These devices offer continuous power of approximately 1 kW and have onboard energy storage capacity of 1 - 10 kWh. The xNode features secure 5G connectivity and satellite data links. Applications that can be served include long-term monitoring using onboard sensors, AUV charging, and data compression and export with the onboard data centre.

Why wave power and why now?

The advancement of wave energy technologies is coming at a pivotal time when dependency on fossil fuels nears the planet’s limit and dependency on existing resources is not enough. Main factors to consider when welcoming wave power into the energy field are that it is more consistent, predictable, energydense, and clean compared to other renewables, making it an exceptional complement to what is available now. F Because ocean waves are always in motion, energy can be harnessed day and night, throughout every season – which addresses key challenges seen in solar and wind.

F Wave power is predictable and can be forecasted two weeks in advance. When complemented with other renewables, wave power can provide a reliable energy supply for coastal communities year-round.

F As the embodiment of solar and wind energy in condensed form, wave power is approximately 30 - 60% more energydense than its counterparts.

F Wave power is clean with one of the lowest lifecycle emissions, and forecasts project that it has the ability to displace up to 1.38 - 1.9 Gt CO2 emissions equivalent

annually.

Humanity is on the brink of unlocking ocean waves as a stable, abundant, and clean resource for power. It is time that these bold and tested ideas are stood behind and adoption is accelerated for the benefit of people everywhere.

CalWave’s mission is to provide clean, reliable, and affordable electricity and freshwater to coastal communities worldwide. The company envisions a healthier, safer, more equitable, and prosperous world – one that unlocks the power of ocean waves to supply 20 - 30% of global energy demand in upcoming decades.