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Not getting barreled: Can wave energy deliver?

Deep Dive with Wavepiston & Horizonomics


Today’s deep dive was predominantly the work of Ravi van Os, who runs Horizonomics. That’s right, it’s a double “van” duo! Ravi interviewed the CEO of Wavepiston, Micheal Henriksen, to ask him a series of trenchant questions with respect to Wavepiston’s efforts to commercialize competitive wave energy systems.

I perked my ears up and chimed in a handful of times because, at the most basic level, myself and many other energy practicioncers have written wave energy off for dead. As far as priors and hypotheses like that go, it’s always worth asking whether we’re wrong about them. I’m also always keenly interested in new ‘clean firm’ generation technologies; if demonstrations and ‘proof’ can prove wave energy can play a role on future grids, I’m all for it.

The newsletter in 50 words: Evaluating Wavepiston, a Danish start-up making electricity and desalinated water by harvesting energy from wave energy. Michael Henriksen (CEO) discusses the company’s recent full-scale installation off the coast of Gran Canaria, the wave energy industry’s progress, and Wavepiston’s position in it.


Nick van Osdol: At the highest level, I think a lot of folks have written wave energy off over the past few years and re-focused on new nuclear, geothermal, and other clean firm power sources. Why are folks like that (including myself) wrong to do so?

Good question, and we are often met with this scepticism that I fully understand. People have tried to get wave energy to be commercially viable for many decades and have not succeeded yet. It is the “yet” that is important here. Renewables like Wind and Solar are fantastic sources with the lowest LCOE of any energy source in the world when we are at large scale. We need to install as much and as fast possible. Geothermal is interesting for specific locations, nuclear can deliver base load but is still expensive and there is reluctance many places in the world due to security issues - several companies are trying to develop cheaper and more secure solutions for nuclear.

With the current geopolitical situation, focus on security of supply (both energy, material and components), where are things manufactured, under which conditions are things manufactured, what is the value of the energy produced incl. when is it produced etc. lead to the increased awareness that we need several sources that complement each other to reduce the risks of downtime, dependency etc. This also means that a price per MWh is not the only criteria.

Hence, it is not “either or”, it is “both and”. Due to the unique characteristics of wave energy complementing especially wind and solar, we also need waves as a renewable energy source. Wave energy is highly predictable, timewise shifted compared to wind and also available at night, it is more stable and available around the world. Last but not least it is an unobtrusive resource, not spoiling the view, environmentally friendly and not taking up land space.

Why has this not been exploited yet? Well, we need to invest. Compared to the other energy sources, both renewables and non-renewables, only a fraction has been invested in wave energy. Now is the time, and we are seeing many interesting companies and technologies getting closer to full-scale and are soon expected to enter the commercial phase with pilot farms as the first step. There is currently a dominant design competition. There will be a convergence to fewer types. We do not believe that it will be one fits all, as waves are different than for instance wind, but several designs based on their application purpose, the conditions, onshore vs offshore etc.

Gran Canaria full-scale installation

Ravi: On the 8th of February Wavepiston installed its first full-scale energy collector, off the island of Gran Canaria at PLOCAN. What can you tell us about this installation’s specifications. How it has performed so far?

Michael: At the PLOCAN site we have installed our full-scale Wavepiston string leading to our conversion station for both power conversion and desalination. On the string we have 20 slots available for mounting our energy collectors for test and demonstration. The power generation unit has a 250-kW generator and the reverse osmosis unit for desalination has a capacity of app. 100 m3 per day.

As this is the first full-scale installation we have a stepwise approach, starting with only 1 energy collector (EC) for “learning by doing” and avoid putting all eggs in one basket. The purpose of the first EC was testing the installation procedures, the operations and the behaviour of the EC. We did not include power conversion / desalination at this stage. Based on this installation we have updated our procedures, and the crew is better equipped for the next step where we in the next weather window(s) will install the remaining 6 energy collectors that we have assembled standing ready in the port. Then we will first turn on the power generation, followed by the desalination.

This means we do not yet have experimental data on power production and desalination vs waves etc. With an impatient soul like mine, it can be quite frustrating with this step-by-step controlled process, but it is important that we do not mess up by making mistakes that can have a serious negative impact on our whole full-scale test and demonstration.

I cannot wait for the moment where we can start sharing data and more videos on the full-scale test and demo!

Ravi: As a relatively new start-up building novel hardware in a new industry, you must have faced a lot of challenges; from supply chains and manufacturing, to permits and local weather. What have been the biggest roadblocks that slowed down the installation?

Michael: It is funny that you call us a relative new startup, in 2024 our company turned 10 years, but yes, there are several challenges working in the wave energy sector in a small company, besides the things related to our technology development, that we also must handle. An example is the work on procedures around the permitting for installations offshore where even the authorities sometimes are not clear what is needed for a test/demo installation, nor a later commercial system. As offshore wind is taking off in many parts of the world, we expect that wave energy can move in the slip stream of this development, although several things are different between wind and waves, for instance the visual intrusion, impact on birds, bats etc. are not an issue for wave energy.

In relation to suppliers, we are trying to make special deals to ensure some priority and good prices, but other times we are often “standing at the back of the queue”. For instance, we are dependent on vessel, crew, and divers to assist with our offshore operations. Normally these are hired by larger companies well in advance for a period of time and then they wait until the right weather conditions for the actual offshore operations. We do not have the funds for this, so we need to prepare everything up front and then look after vessel and crew availability as soon as weather conditions are favourable. This is of course quite frustrating and is delaying our work and testing, but something we must counter for in our planning.

The last thing is in relation to our own capacity in Wavepiston. We are only 12 people working in the company, which reduces the band width. When we have too many parallel tracks ongoing, we increase the risk of errors. We have made mistakes, that cannot be avoided, fortunately so far nothing that has shaken the foundation of Wavepiston, but we are very aware of this and preach “quality” the whole time. We need to learn from these experiences and ensure that we at least do not repeat our mistakes or mistakes historically made by others.

Ravi: The system has now been in operation for a few months. What do you expect in terms of seasonal variation in electricity generation?

Michael: Seasonal variation is site dependent. At the PLOCAN site on the east coast of Gran Canaria the waves are quite stable over the year, with a bit more energy during the summer months July-August, and a bit less during September-October. And then it can also variate over the years. At other locations it is more seasonal, like in the North Sea where the power curve looks like a smile, with a lot of energy in autumn, winter, spring, and then limited energy in the summer months.

Ravi: Let’s say you had to build an exact copy of the Gran Canaria installation for a client right now, where would you be at in terms of total cost? Of course provided this is before any cost reductions through scale-effects.

Michael: We would be at an LCOE of around EUR 350 – 400 per MWh assuming a 2 MW system, i.e. 6-8 strings in a good wave climate. This is of course not commercially viable. The Gran Canaria installation is our first full-scale prototype. We are in parallel working on our commercial version, where the first commercial wave energy farms are expected to have an LCOE of EUR 100 – 200 per MWh depending on site and size.

Ravi: Finally, what results do you want to see from this project over its first full year, to consider it a success?

Michael: We need to see an energy conversion that is according to our numerical model aka digital twin. And that we can produce both power and desalinate seawater. I.e. real data that can be validated by third parties. Besides the actual wave energy converter, our instrumentation (sensors, data collection etc.) is key to achieving this. Here we have both pressure, load and position sensors, plus cameras mounted on the system in the water, and we are of course measuring flow, power and desalination at the conversion station. Finally, we need to learn from and document our installation and offshore processes and procedures. This will support the optimisation of not only the technology but all the things that impact the LCOE.

Wave energy’s position in the renewable energy sector

Wavepiston installation at PLOCAN, Gran Canaria

Ravi: While all renewable technologies are on the same side to decarbonize our electricity production, they are in different ways both competing and complementing each other. Do you expect to eventually compete with solar/wind/others directly on a per kWh basis? If so, what is the timeline and scale needed?

Michael: We will compete but as said, mainly complement each other. As an example, why are we contacted by island nations around the world? Because they cannot cover their needs with solar and wind alone due to the intermittency, the available land space, and the conditions at sea. They need other sources where many islands and coasts have a good wave climate.

To compete 1-1 on price we are looking 10-15 years ahead for utility-scale wave farms of hundreds of MW, but as said, we are not talking about 1-1 comparisons here. What do we do when the sun is not shining, and the wind is not blowing? Studies in UK on bringing 10 GW into the UK grid have shown a positive impact of GBP 1.5 billion per year and that producers are able to get up to 2.2 times the price compared to wind and solar due to the differences in the production patterns. Secondly what do countries, regions etc. do if wind and solar are not good or sufficient options for them?

Ravi: In your discussions with potential partners, specifically end-clients, how important do you think the low-visibility of Wavepiston is compared to wind turbines for example?

Michael: This is an important factor, especially for islands and coastal communities where tourism is important. Even locations without a large tourism industry have encountered large resistance from local stakeholders. Please note, I think that wind turbines are great. I think that cooperative thinking is important, getting local stakeholder involved and co-owning energy farms, and hopefully farms with several sources to reduce the need for storage and increase self-sufficiency without the need of fossil fuels.

Ravi: You have received multiple grants through different European Union initiatives, as well as one from the Danish EUDP (Det Energiteknologiske Udviklings-og Demonstrationsprogram). To what extent has this made a difference for your company, and is there anything about these initiatives that you would improve?

Michael: The public co-funding is crucial for us. Due to the high-risk and long-term investment, the private investors will not take this risk alone. By having both the message from the politicians and authorities that they believe in this, and the money to back it up, the private investments can leverage on this.

Rather than grants or funding, which is often used, I would like to call them public investments, as the short-term expenditures in R&D&I are benefitting the industries and academia we are working with, and the outcome when wave energy become a successful, commercially viable energy source will have an immense value on both the climate, the environment, and the society.

Ravi: Considering these are mainly EU initiatives, how has this influenced your target markets? Are you considering EU locations over non-EU small islands due to this?

Michael: Yes and no. The world is our market. Having said this, we have in our first step focused on locations where the “non-technical” challenges are as few as possible. There will always be these challenges, but there is a difference to install a wave energy farm in a location that already has a good infrastructure compared to one where there is a high dependency on other investments. This means that we have focused on European related locations to begin with.

At the same time, we also need to “follow the money” and support. So, if there is a large support and a higher likelihood of funding, then we are also looking at these sites.

Ravi: The United Kingdom’s Contracts-for-Difference auction on March 27 has a minimum of £10 million allocated for wave energy, with a strike price at £261 per MWh (2012 prices). Wave energy will specifically be added as a separate technology for the first time, however with a slightly lower strike price at £257/MWh (2012 prices).

Will you be attempting to win a contract under the upcoming auction?

Michael: The CfD programme in the UK is of utmost importance showing a way forward to get new, innovative renewables to the market. We will not bid on the upcoming auction as there are a number of requirements on surveys, leases etc. that require large, upfront investments. We are simply not ready and do not have the funds for this. We are having the UK as one of the first markets we want to enter and expect soon to be ready to enter partnerships on bidding for the CfD auctions to follow.

Ravi: What do you think about the difference in strike prices for tidal and wave energy?

Michael: The strike price level as such, I think is very interesting and seems to be at the right level. Why there is a lower strike price on wave compared to tidal, I do not understand. Tidal is more mature, although with less potential worldwide. Both EU and the sector estimate that the first couple of years wave energy will have a higher LCOE compared to tidal.

Ravi: To what extent are wave energy installations in competition with offshore wind turbines for sea area or maritime territory?

Michael: In my mind, limited competition. We need to see these areas as offshore energy areas where we will install both wind and wave to maximise the output of a given area, increase the quality of the generated power and reduce the total price for renewables (not only LCOE). As the areas between wind turbines get larger due to the increasing size of wind turbines there comes more and more space available for co-location.

Ravi: Considering the harsh sea conditions of high waves, storms, salt, and bio-organisms - how long do you expect the system to remain functional, and how important is finding willing insurers for commercial rollout?

Michael: We are working with lifetime of minimum 20 years including planned maintenance. To make the wave energy farms bankable we need to be able to insure them and give guarantees. This is crucial. There have been initiatives on an insurance and guarantee fund for the first period of time until the sector matures. It is possible to insure the farms but the premiums have been high. Until the sector matures and we get enough experience with wave energy farms, certifications etc. we must focus on the commercial pilot farms to show results and give confidence in the sector.

Wavepiston’s position in the wave energy sector

Ravi: There are a number of competitors within the wave energy industry, including Eco Wave Power, CorPower Ocean and Weco. What sets you apart from them?

Michael: There are many good companies in the sector with interesting technologies. The main difference of the Wavepiston technology compared to the others are our patented force cancellation concept that reduces the mooring loads on the system to less than 1/10 compared to individual modules/WECs installed at sea, and the simple, low-tech solution at sea with a passive control system. Due to our concept, we do not need active control and complex solutions at sea. We convert to pressurized seawater which due to the many modules results in a very smooth flow that is transported to a common conversion station in a dry place, either on a platform or on shore. This enables the possibility to both produce clean electricity and desalinated water, one, the other, or both at the same time.

In this way we get a simple, low-tech system, with the lowest weight per effect in the sector, on par with the best bottom-fixed wind turbines. And weight equals cost when you start scaling.

Ravi: The CEO of Eco Wave Power, Inna Braverman, projected that their average cost per kWh would fall to €0.05 once they reach a scale above 20 MW. How does this compare to your estimates, and do you think this is realistic?

Michael: I will not comment on the estimates from my colleagues in the sector. I can say, that Wavepiston believe we can get down as low as EUR 40 per MWh at locations with a good wave climate. This will require utility scale farms and 100s of MW, maybe even several GWs installed. We expect this to happen within 10-15 years.

Nick: Panthalassa is a stealthy; they seem well funded. Have you heard much about them or taken time to dissect their approach? Seems like they’re less interested in connecting to grids than using wave energy to power other processes, like making green hydrogen or other fuels. 

Michael: No, I have not analysed them. New ideas, technologies and companies emerge, and others disappear. We try to stay on top on what is happening in the sector and collaborate with several of our competitors, for instance in relation to regulations, support, etc. With some of them we also discuss common technical challenges. On European level we are members of Ocean Energy Europe. This is important, to have one common voice in Europe and the world.

Ravi: If Wavepiston’s energy collectors were installed across an entire square kilometer, what would be its MW rating?

Michael: We estimate 10 – 15 MW per km2, depending on the wave climate.

Ravi’s Note: For comparison, European off-shore wind farms have a mean of roughly ~7 MW/km2 , with ranges from 3 - 20. Source here.

Future roadmap

Ravi: You are conducting a pre-feasibility study with Export Barbados (BIDC), and have signed an agreement with YS Energies Marines Developpement (YS~EMD) to co-develop a wave energy installation. The CEO of YS~EMD has said “We are convinced that wave energy is now ready for a commercial phase and will play an important role in the decarbonization of islands’ electricity mix around the world.’’

What can you tell us about the financial structure of this project, considering it does not name any subsidies, and is presumably not cost-competitive at this stage?

Michael: We are currently at the stage of pre-feasibility. We have already made a study of the coastline of Martinique and the grid, partly funded by the French agency ADEME. The current pre-feasibility activities we are funding ourselves from our equity. We share the costs 50/50 with YS~EMD. The plan is to start with a 2MW pilot farm with public co-funding and then extend this to a commercial farm in the next step.

Ravi: Shell Technology’s Marine Renewable Program has partnered up with Wavepiston to conduct a desktop feasibility study. What do you concretely expect to gain from this?

Michael: Shell Marine Renewable Program is collaborating with several actors in the sector. For us, this is the beginning of a relationship that will hopefully flourish and expand as we together identify specific projects with common interest to collaborate on and install wave energy farms to replace fossil fuels.

Ravi: You’ve recently been awarded a grant by Horizon Europe to develop a seawater hydraulic power-take-off (PTO) system, coupled with an advanced control strategy. Can you explain how and to what extent this could improve the levelized cost of energy (LCOE) of your system?

Michael: This is a part of our technology roadmap, focusing on our main cost driver, our energy collectors, replacing steel parts with composites and optimising our control system. The expected impact is two-fold, both a cost reduction due to lower CAPEX going from high-grade steel to composites, reducing the need for extra buoyancy, lower the OPEX via better durability i.e. longer lifetime, and increasing the conversion efficiency. We have high ambitions in this project together with some very competent partners.

Ravi: You communicated a recent capital raise, with the equity issue scheduled 16 February - 1 March 2024, what can you tell us about this raise? And how does it fit into your goals of reaching the financing needed for cost-competitive scale production?

Michael: This is a part of a EUR 1.5m raise we are having in H1-2024 to secure funding to a) Test and demonstrate results from our full-scale system during 2024, b) Continue our technology development, c) Continue our project development, focusing on the commercial pilot farms to begin with.

Based on this, we are planning for a large raise in 2025 with one or several strategic investors.

Ravi: What are the next concrete steps for Wavepiston this year?


  1. Show successful results from our full-scale installation

  2. Continue technology development on the commercial version, first iteration ready

  3. Landed an agreement on first commercial pilot farm

  4. Secured a strategic lead investor for our 2025 raise

  5. Secured a strategic partnership with an industry company in the sector

Ravi: What would you like to have achieved in 10 years, around 2034?

Michael: We will be the largest wave energy company in the world, having installed over 1 GW of wave energy farms, and having 5 GW sold capacity in our books. Making a large positive impact – this is why we are here!


Ravi & Nick