3. Fishing and aquaculture vessels with alternative power sources

The first French oyster barge with electric propulsion, François Cadoret, was inaugurated in July 2022 for Breton oyster farmers. The barge, 11.90 m long and 3.70 m wide, is powered by two 70 kW electric motors and has two 40 kWh batteries charged via solar panels and two small wind turbines. Construction cost €250 000. Later, it will be able to receive a hydrogen kit.

Astrid Helene was one of the world’s first (entered into service in 2017) fully-electric workboats with no engine noise, no diesel fumes and zero emissions. This is advantageous for aquaculture as the vessel avoids any environmentally hazardous emissions and has low noise. It is 13.9 m long and 7.6 m wide with a battery power of 340 kWh. Estimated annual savings are 80% on maintenance costs, with 33 700 litres of diesel/year saved and with 90 tons CO2 emission reduction.

The 87 m Ronja Star is the largest well boat fish farming vessel in Scottish aquaculture. The hybrid vessel is fitted with diesel electric propulsion¹ and a battery hybrid solution which reduces fuel consumption and emissions, all while generating less noise. Other innovations include state-of-the-art life support systems, which includes high-capacity oxygen production, a carbon dioxide removal system, and a water-cooling system to ensure the fish are kept in optimal condition during treatment. In addition, it has an automatic cleaning system, alongside sensors and cameras to monitor fish and water quality.

MDV-1 Immanuel, a hybrid electric-diesel fishing vessel, was specifically designed to be an innovative fishing vessel to test ground-breaking innovations in practice. The special shape of the ship and the diesel electric propulsion provide 60% fuel and CO2 savings compared to similar-sized fishing vessels. In addition, a number of other innovations in the ship's design and build were made, namely on the hull shape, fishing techniques and handling, materials used and other onboard energy-saving measures. For example, the uninterrupted, automated fish processing and cooling ensures that this process goes faster and the fish stay fresh longer. A sister ship MDV 2 ‘Metanoia’ was also constructed, and entered into service in 2020.

The 11-metre fishing boat “Karoline”² was developed by Selfa Arctic AS (Norway) and Siemens for Norwegian fishing company Øra AS in 2015. The vessel has a large 195 kWh lithium battery pack and 50 kW diesel generator. It is designed to operate solely on battery power over a 10-hour period, and to charge overnight by plugging into the electrical grid. It will thus burn no fuel in normal operation, but, by having a generator on board, it will not be range-limited by battery capacity when making longer passages. The same designer also developed a successor “Sundsbøen”.

NB65 Hardhaus, 74,5 m long, 16 m wide purse seiner/trawler is equipped with the most efficient diesel engine (according to the Guinness World Records) supported with 1 017 kWh battery power for both peak and emergency sources of power. Winches are operated by battery power and the vessel can operate on battery in manoeuvring and in harbour to minimise noise and local pollution. The optimized hull shape minimises wave resistance, thereby saving energy. There is also an automatic heat recovery system and the vessel barely needs heating systems onboard.

According to the shipbuilder, the 21 m long MS Angelsen Senior is the world’s first fishing vessel of this kind to have a battery hybrid solution. It reduces running hours on the engines by 75% and saves 25% fuel, equivalent to 75 000 litres of diesel and 200 tons of CO2, and more than 50% of the maintenance costs. Batteries are charged while engines are running and in port. Running on electricity means less noise, less vibration and a safer work environment. The ship is designed to operate on battery power when there is a low power requirement, such as when laying to or hauling, and to switch to diesel-electric mode when shooting the gear or steaming at up to ten knots, which also provides an opportunity to charge the battery packs. There is also a heat recovery system to route excess heat to where it can be best utilised.

The 87 m long pelagic trawler/ purse seiner, Isafold (DK), was built with diesel-electric propulsion, with both the twin propellers and the winch system based on high-efficiency permanent magnet motors. The combination of five medium-speed generators and a 1 130 kWh battery pack ensures optimal production and use of energy under any scenario, while the twin propellers require minimal energy and provide excellent manoeuvrability, especially for trawling.

The company Seigur Boats (Norway) has developed a transfluid hybrid propulsion system for a fishing vessel expected to enter into service in 2023³.

This hybrid system will be used in conjunction with a diesel engine plus 400 Ah battery bank, which can be recharged by the regeneration system of the hybrid system or with the onboard generator. With the special transmission, it is possible to integrate diesel engine power with the hydraulic and electric utilities on board and to cruise at approximately 8 knots in electric mode.

The Norwegian company, Liegruppen, is the first fishing company to have a trawler powered by liquefied natural gas (LNG), the Libas. The engines will run on both LNG and diesel, resulting in approximately 80% estimated NOX emissions reduction and 24% estimated CO2 emissions reduction.

The biggest challenge in designing the vessel was the space. In order to accommodate the large LNG tank, which had to be additionally insulated, and the associated equipment and still have sufficient space for the fish tanks, the ship had to be constructed larger than usual. It now has a length of 85 meters, which is almost 20 meters longer than its older siblings. In addition, the way a fishing trawler operates places special demands on the engine. The engine of a fish trawler has to be able to adjust well to constantly varying loads. For diesel engines, this is no problem, but it’s difficult for a gas engine to cope with load changes.

But reducing a vessel’s ecological footprint comes at a price. The LNG-powered trawler cost about 30% more than one with a conventional engine. In addition, there are the costs of training the crew.

The 86,50 m metre Sunny Lady is a LNG-powered pelagic vessel with hybrid propulsion provided by a 350 cubic metre LNG tank and a 1 024 kWh battery pack.

The battery arrangement provides for peak saving to optimise the main engine’s operation, and also allows for energy regenerated from the winches and other systems to be routed to the battery and made available for use elsewhere.

Following a call for projects on hydrogen for fishing, the Brittany (FR) regional authority selected (in December 2022) two projects, named Pilothy (with €87 000 funding) and Estebam (with €249 000 funding). They aim to establish, in less than a year, a technical, regulatory and economic roadmap for the integration of hydrogen fuel cells into existing vessels, the former for fishing boats, the latter for some 60 shellfish amphibious barges.

The Pilothy project, led by Barillec Marine with the support of a consortium of companies, members of the Interprofession of the Port of Concarneau, aims to study the integration in existing old vessels of hydrogen fuel cells as an alternative to diesel engines. The first part of the project is a feasibility study that will address some of the current regulatory, financial, and technical constrains that are preventing the use of hydrogen in fishing vessels (i.e., lack of space on board, regulatory aspects of the integration on board, etc).

Anita Conti is the study trawler that will be part of the Pilothy project in the port of Concarneau. The vessel that measures 17,30 m long and 5,64 m wide and was built in 1985, will be used as a pilot to support a series of tests in fishing conditions.

The project “Filhypyne”⁴ in France has developed since 2014 a trawling vessel using hydrogen propulsion. While the project seems to be looking for financial support, it has already agreed a three-stage planning with the research and sectorial partners. The stages of the project are intended to validate the technical, economic, environmental and social performance of the hydrogen-fuel cell technology in actual professional operating conditions. After the installation of the propulsion system in the fishing boat demonstrator and its qualification in harbour and sea trials, the third stage would be coordinated by fishers and consist of a tour of France’s ports, to have the demonstrator validated by its future users.

The Norwegian company Skipsteknisk designed what may be the first hydrogen-powered fishing vessel, the 70m Norwegian longliner, Loran. While the vessel still has conventional diesel engines, it also has in addition two 185-kW hydrogen fuel cells and a 2 000-kWh battery bank. It entered into service in December 2022.

The vessel has multiple propulsion options — diesel and electric power to the main propeller, as well as a retractable azimuth propeller in the bow for when they are hauling the longline, and for redundancy, in case something ever happened to the main propeller.

The real challenge with hydrogen is sustainable generation and storage onboard. The hydrogen system is above deck as there are no safety standards yet for putting it below deck. The hydrogen is stored as gas at 5 000 psi in ten 20-foot-long tanks aft of the wheelhouse, with the fuel cells close by.

The Loran project is subsidised by the Norwegian government and other investors. Enova, an agency of the Norwegian Ministry of Climate and the Environment, put over $10 million into the project. The hydrogen auxiliary power is expected to reduce fossil fuel use by 40% and is seen as a step toward a zero emissions future.

The Catalan maritime sector has two on-going projects to change energy sources depending on the size of fishing vessels.

The project “Sailfish” is developing two prototypes in the framework of the 2030 Maritime Strategy of Catalonia. The vessels concerned by this technology would be between 17 m for purse seiners and 24 m length for trawlers. The sails would secure an alternative energy source for the vessel propulsion.

Another project is looking at the design of a fishing catamaran that would use solar panel for an electricity engine. The selected vessel is of 8 m length from an artisanal fisher collaborating with a research group of the Nautical University of Barcelona⁵. In addition to being silent, the annual reduction in CO2 emission reaches 1 600kg.

Wind energy is seen as one of the most promising sources of alternative energies for sea-going vessels⁶. A variety of methods/technologies have been explored to harness the power of wind energy, although currently mainly for larger ocean-going vessels⁷. These include fixed (or inflatable⁸) sails, Flettner rotors, skysails or kites⁹. Lloyds Register has approved a rotor sail for cargo ships.

Some examples of developments for fishing vessels are outlined below. The International Windship Association (IWSA) has done some consideration for fishing vessels and there are activities in Brittany (FR)¹⁰ too.

3.14.1 Fishing vessel, Maartje Theadora¹¹ 

With funding provided also by the earlier European Maritime and Fisheries Fund, a 160 m² SkySails system was installed aboard Germany’s largest fishing vessel – the 141m long ROS-171 Maartje Theadora – in 2010. Because operating conditions on a fishing vessel differ greatly from those of a commercial cargo ship, especially during trawling operations, the key focus of the trials was on technically adapting the system to the circumstances specific to fishing operations. Its maiden voyage with SkySails propulsion took the ship across the Atlantic to South America and then into the South Pacific. However, since these trials it seems that the system is no longer installed on the vessel.

3.14.2 Fishing vessel, Balueiro Segundo¹²

The Balueiro Segundo from Vigo (ES), in 2021, was the first fishing vessel in the world to be equipped with an auxiliary wind-assisted propulsion technology and also the first vessel to install Bound4blue’s eSAIL® technology.

The system uses the wind to propel the ship, thereby reducing fuel consumption and pollutant emissions released into the environment. It was developed within the framework of the Aspiring Wingsails project, co-funded by the European Union (via EMFF), the Norwegian company Kyma, and the Spanish company Bound4Blue. It will monitor and validate fuel savings and reductions in emissions during sea trials in the Pacific Ocean (from Panama).

3.14.3 Adaptations to small fishing vessels to use wind power

There do exist some start-ups promoting the use of sails and providing the means to convert fishing vessels.

The Skravik project ¹³,  which receives EU EMFAF funding, aims at reviving wind propulsion for small-scale artisanal fishing. By adapting a prototype catamaran, the project aims to reduce the environmental footprint of fisheries in coastal areas by reintroducing sailing as a way of sourcing food sustainably.

The vessel is tested under real fishing conditions with traps, longlines, lines and nets in the maritime territory of Brest, France. It is also the intention to transfer experiences and lessons learnt to larger vessels, other fishing techniques and offshore fishing.

Two other examples, from SailLine Fish and from Avel Tor Technology, are presented below. SailLine Fish (UK) aims to develop a zero-emission fishing operation where wind energy both from sail and turbine generated can power fishing vessels and shore facilities. On route to this goal it developed the “Balpha Mast,” a sailing mast system that can be retrofitted and easily raised and lowered while the vessel is at sea, thus enabling maximum use of this free resource.
 

Avel Vor Technology (FR) installed automated sails on the laboratory boat Grand Largue, a former 16m length wooden trawler. Sea trials have shown that the sails allow decreases in fuel consumption (depending on wind conditions and heading) and that they consistently improved boat stability. They also work on sails shaped as an airplane wing, or wing sails, having a better efficiency.

The Just add water project, is based on Atlantic Salmon fish grown using Recirculating Aquaculture System (RAS). The bacteria in the water produced by this technique are usually absorbed by the fish and the current depuration treatment consists in an equipment and energy expensive 12-day treatment. The Univerisities of Trento and Bologna and the Innovation Hub of Trentino (HIT) with funding from the EIT food, will develop a technology that will reduce the energy consumption as well as increase fish welfare and fish weight by eradicating the bacteria. This technology is based on a filtration unit that together with Unitn Sys PO water treatment will increase the animal welfare and reduce the energy-expensive 12-day treatment. This technology can be further applied to other aquaculture species.

The project is in an advanced state of readiness, with planning consents and licences granted, but the testing phase and implementation has not started yet. New technology will reduce energy consumption, fish weight loss and stress.

The Danish shipyard Hvide Sande has chosen the company Corvus Energy  to provide a complete hydrogen fuel cell system for the training vessel MS Skulebas.

The 35-meter fishing and training vessel is a model of innovation and teamwork in the maritime and educational sectors and is equipped with the most recent technology and commercial fishing equipment. The vessel will be the first of its type, integrating both fuel cells and batteries in a fishing vessel. It is owned by Vestland County and managed by Måløy Upper Secondary School. 

The MS Skulebas is outfitted with Corvus Energy Orca batteries, which will function in tandem with the Pelican Fuel Cell System, a polymer electrolyte membrane (PEM) hydrogen fuel cells that will deliver a 340kW. The company Hexagon Purus will be in charge of managing the storage solutions for the hydrogen. Combining these two technologies will allow to considerably increase the range of zero-emission operations. The vessel will conduct the majority of its operations fully electric and will be supplemented by clean hydrogen-powered energy when needed.

An electro-hydrogen 20m Zero Emission fishing vessel is the result from a collaboration between MAURIC and Alternatives Energies, Chantier Naval Gatto and EODev companies. This vessel is built with support from the France AgriMer 2021 call for projects. First trials and sailing are expected for beginning 2024.

The vessel will be equipped with two hydrogen fuel cells of 70kW, fed by 9 hydrogen tanks installed on the main deck, and by batteries and is set to have a range of up to 100 Nautical miles. The hull shape has been optimized for speeds between 8 to 12 knots, has an integrated sonar for halieutic research and space for a dinghy. The fishing gear included are removable winches and hoists for long line fishing and purse, and two fixed hydraulic cranes. As the MS Skulebas,the fishing vessel is also thought to be used as a training vessel to combine fishing activities with teaching of hydrogen fuel operation and maintenance techniques.

Ilha da Culatra, in Ria Formosa, is where 41% of Portugal’s aquaculture takes place. As part of the “Culatra 2030 - Sustainable Energy Community” initiative¹⁵, the Culatra harbour aims to install a photovoltaic plant of 64 kWp; a 32KwH energy storage unit; a pilot solar-powered vessel for use by all the shellfish growers in the community; and a charging station to sustainably support aquaculture and tourism. It also aims to support the development of a local micro-grid concept that enables the effective management of available energy resources at peak hours and the intelligent use of energy.

The project is promoted by AMIC and Sun Concept, the latter of which is a Portuguese shipbuilding company that specialises in the development and manufacturing of vessels with solar-electric propulsion. To showcase the boats innovative technologies and encourage the community to transition from engine vessels to solar-electric ones, the community in Culatra will be able to test the solar-powered boats themselves. After all, the vision of the Culatra 2030 Initiative is to create an energy community that manages its own energy and shares it.

Project Octopus in an innovative and sustainable ship focused on the future of fishing. The aim is to produce a multifunctional vessel, that not only is built sustainably, but also use all the data obtained for multiple purposes. The projects' goal is to create a ship that can be used for sustainable fishing, maintenance and management of seaweed, research, and coastal surveillance.

The vessel is fitted with a diesel-electric propulsion and a battery to store the self-generated energy and is built to practice flyshoot and twin rig fishing. However, due to its easy convertibility, other fishing techniques are not excluded. The ship collects all type of data which is shared with researchers and scientists and used for a more targeted fishing. The vessel is equipped with a sonar and a drone to contribute to the coastal surveillance. Moreover, the construction of the vessels is circular, using raw and composed materials and avoiding residual flows, as well as using material passports to promote circularity and transparency. The multifunctionality of the vessel promotes cooperation among different stakeholders and generates a stale income stream.

The FINO3 Platform, run by FUE and situated 80 kilometres offshore in the North Sea, is the ideal setting for testing and showcasing an aquaculture business that is economically feasible. The sustainable farming of seaweed and mussels is combined in the German North Sea experiment. At this location, FUE is presently conducting multi-use research trials as a part of the Horizon 2020 UNTIED project.

The pilot's goal is to design the operation of all system components, including the seaweed and mussel cultivation elements, as well as their possible combinations along the edge of an existing wind park.

Techniques for sowing and strain development of seaweed species that are more lucrative will be investigated for offshore production.

In addition, the pilot will experiment with the possibility of using locally produced renewable energy and investigate interactions between target culture species and the offshore environment in order to develop environmental protection strategies.

The HYBA project , led by the Bretagne-Atlantique fishing industry and supported by maritime, fishing and energy optimization specialists and scientists, will contribute to developing a tailor-made hybridization and energy optimization solution for trawlers and their fishing gear. The project is based in using machine learning to create a tailor-made hybrid dimensioning and strategy for each existing vessels according with their type of vessel and fishing practice, and the optimisation of the fishing gear.

The project is divided in pre-study of the technical-economic aspects of the project and the development and integration of the project in a pilot vessel. The pilot study will be based on the adaptation of Naoned, a 23m multipurpose trawler from Armament APAK.

The Blue Wave vessel, anchored in Guilvinec, is the first 22m deep-sea French trawler to run on a diesel-electric propulsion system. The electric propulsion package comprises a 500kW permanent magnet synchronous motor with a speed of 175rpm, a variable speed drive enclosure for the motor and a liquid cooling kit for the unit. In addition, it is powered by two 400V-600kVA and 350kVA diesel generators.

The possibility of having several generations means that the number of diesel engines turned on can be adjusted depending on the vessels load, leading to a lower diesel consumption and an adaptive usage. The project results in 30% reduction of the fuel consumption and less noise and vibration.

Julien Le Brun, owner of the Anita Conti, vessel used for the Pilothy project, has acquired a new vessel, the Magali anchored in Loctudy. The naval architect Coprexma will transform the engine of the 17.5m trawler to a hybrid technology, with an electric propulsion powered by a diesel generation. This has the potential to reduce the fuel consumption of the vessel by 20%. The technology used in this vessel is the same as in the Blue Wave vessel anchored in Guilvinec.

The North Salmon Service is working together with HAV group to develop an emission-free wellboat to reduce the carbon footprint of aquaculture. The six-month preliminary project has been launched and will build a vessel designed with the most advanced equipment to reduce fuel consumption and will be propelled by a dual-fuel engine using ammonia as fuel.

Ecomotus has developed the EcoPro Electrolyser to reduce the pollutants released by the vessel's engine. The system consists of the electrolysis of deionized water that will allow the use of the hydrogen in the combustion process. This methodology eliminates the need for hydrogen storage space on board and only requires for an electrolyser cell and deionised water.

This technology has already been tested in two vessels: the Crystal Sea, a 24.5-metre twin-rig trawler, operating with the EcoPro electrolyser since January 2023 and has reduced around 8% of fuel consumption; and the Emma Jane, an 18-metre crabber, that has been operating with the EcoPro electrolyser for four years now and has reduced around 10% of fuel.

Cooke’s Copsiter salmon farm in Shetland has installed a new hybrid system built by Fjord Maritime UK. The feed barge uses a hybrid system that reduces the fuel consumption and the carbon dioxide emissions. The diesel generator provides energy for the facility while charging the batteries. Once the batteries are fully charged the engine stops. The batteries autonomy is of 20 hours leaving 4-6 hours for the engine to work and restart the cycle.