Final ReportSummary - CLOSEDFISHCAGE (Development of an innovative, cost-effective environmetally friendly closed cage for sea-based fish farming)
General information about the CLOSEDFISHCAGE project
The CLOSEDFISHCAGE project is a Seventh Framework Programme (FP7) project for 'Research for small and medium-sized enterprises (SMEs). It had an official start date of 1 September 2009, and has a complete duration of 24 months. The beneficiaries in the project are as follows:
- Plastsveis AS (SME and coordinator)
- Burashi Italia srl. (SME)
- Studsgaard AS (SME)
- SeaFarm Systems AS (SME)
- Cultivos Marinos Del Maresme SA (SME)
- Fjord Marin Holding ASA (OTH)
- Seawork (Scotland) Ltd (research and technology development (RTD) provider)
- Teknologisk Institutt AS (RTD)
- Politechnika Gdanska (RTD)
- Technologías Avanzadas Inspiralia SL (RTD)
Complete project description
CLOSEDFISHCAGE has focused on the development of a closed, escape proof, constant volume, sea-based cage for fish farming. Among the project's innovative elements are a very durable and flexible polymer plastic net pen, a predator guard, a control system, easy set-up and replacement of damaged cage parts and water treatment and control system. The technological solutions involved in the sea-based cage will preserve advantages of land-based fish farming while at the same time taking advantage of the cost efficiency of sea based fish farming.
The scientific research objectives and the specific technological objectives of the CLOSEDFISHCAGE project include:
- identify the physical, chemical, biological, regulatory aspects as well as good husbandry practices of sea based fish farming for target species and these aspects must be considered and linked to the development of closed cage and water treatment and control technologies to be developed in WP 2 and 3;
- identify and calculate key oceanographic data in order to model the environmental forces on the closed cage in order to ensure a design and technical solutions ensuring a constant water volume during different weather conditions;
- development of a closed cage with a volume change of less than 10 % during different weather conditions;
- development of a water treatment and control unit that will ensure optimal water quality with a change in oxygen level of less than 10 % compared to target setting during the day and a daily temperature fluctuation of less than 1.0 degrees Celsius.
Project context and objectives:
In our project we have had the objective to create a closed cage for sea based aquaculture in order to give the farmer more stable and better control of environmental parameters, such as O2, ph, and temperature, and to remove / reduce the risk of sea lice, harmful algae and jellyfish, in addition to reduce / remove the risk of predators getting into the farming units. The system will also have the possibility to clean all effluent water, similar to that of land based facilities.
Project results:
Description of the work performed and the main results achieved
The description of RTD work and main results are as follows:
WP1: Enhanced scientific understanding of biological, physical, operational and regulatory requirements for sea based fish farming
Objective:
To create a detailed understanding of which biological, physical, operational and regulatory requirements that need to be considered and applied for the technology to be developed in the proposed project, with respect to development of closed cage and water control system.
Results:
The main results from the work carried out in WP1 are presented in the following two reports:
- Report D1.1 - Reference document describing internal factors including biological, physical, chemical and operational criteria for consideration during development of closed cage and water control system.
This report identifies different fish species relevant for the project and the operational requirements including feeding, dead fish collection, cleaning of bio-fouling, water treatment, technical installations, monitoring and alarm systems, biomass monitoring, light manipulation, service and work vessels, grading and moving fish. (public)
- Report D1.2 - Reference document describing external factors including oceanographic conditions, regulatory requirements and existing infrastructures.
This report identifies oceanographic data including ocean current, wave height and salinity and temperature and existing infra-structures including surface cages - steel, surface cages polyethylene, submersible or semi-submersible cages and current trends in cage development. Not primarily in the description of work (DoW), but decided at the kick off meeting, evaluation of potential harmful organisms including harmful algae, harmful jellyfish and salmon-lice was included. Results have continuously been communicated to RTD partners and provide input to development in WP2 and WP3. The results are included in deliverable D1.1. (public)
WP2 Development of closed cage
Objective:
Based on specifications from WP1:
- develop a closed sea cage including material selection and design of closed net;
- build prototype;
- perform functional tests;
- optimisation of prototype;
- prepare for integration with water treatment and control system.
Results:
- Report D2.1 - Report describing the development of the prototype of closed cage for sea based fish farming
Present document describes first development phase of CLOSEDFISHCAGE project. In order to release a design compliant with such a wide range of constraints has been chosen a systematic approach. This approach is as follows:
(1) a definition of application driven requirements;
(2) fitting general requirements down to the level of prototype technical goals;
(3) study and definition of canvas optimal shape; and
(4) based in previously defined requirement baseline, as well work environment to perform canvas materials selection. The results are included in deliverable D2.1. (confidential)
- Report D2.2 - Prototype of the closed cage
This report covers the development effort carried out in order to establish the more rational canvas shape, as well the prediction of forces due to the effect of marine environment. In addition, the following criteria has been considered:
- stability of canvas shape;
- wetted exposed area;
- allowed membrane stress versus water head;
- effect of volume variation versus increase of water head.
Further there has been carried out two towing scale test, under different motion conditions. Obtained results allow us to predict the forces due to flow motion and inertial forces due to wave patterns. The results are included in deliverable D2.2. (confidential)
WP3 Development of water quality control system
Objective:
Based on specifications from WP1:
- development of water treatment and control technology in order to ensure good water quality including water intake at different water depths for variation in temperature, water inlet and outlet in closed cage and determine hydrodynamics in closed cage for homogenous water quality and sensor and control system;
- build prototype;
- perform functional tests;
- optimisation of prototype;
- prepare for integration with closed cage developed in WP2.
Results:
- Report D3.1 and 2 - Report describing the development of the prototype of water treatment and control system and set-up and result of functional testing of the water treatment and control system presenting both the theoretical work and the physical work, testing and integration that was done.
We have tested and validated the system at an end user locality (Norsk Havbrukssenter), and made further calculations regarding dimensioning of inlet and outlet pipes and flow, both with the dimensions that were used for the prototype and alternative dimensions and their resulting possible flows. In addition, we have made further calculations for scenarios using a commercial scale version (70 m circumference) of the CFC, which are also presented in D3.1 and 2. Included in D3.1 and 2 is also the technical description of the control system, relating to task 3.2 and data collected for water quality parameters by the control system. (confidential)
WP4: System integration and industrial validation
Objective:
Integration of the sub-parts produced in WP 2 and 3 in order to obtain a fully functional CLOSEDFISHCAGE system. Validation of the CLOSEDFISHCAGE system by demonstration of the fully integrated technology against the project objectives incl. benchmarking compared to existing technologies and economic analyses of cost effectiveness of new technology.
Results:
- Report D4.1 - Report describing the work performed in WP4, including the building of prototype(s), system integration, functional testing, benchmarking and analyses of cost efficiency.
The main focus for WP has been directed towards validation of fully functional prototype, which specifically means: a prototype capable of supporting the production of fish. The validation process was carried out over an extended period of 10 months. The report also includes the finite element model we developed and it has been upgraded in order to reproduce the Toft prototype's actual constructive solution, stresses and dynamic response. Using this upgraded numerical model we have run computer simulations for sea conditions corresponding to a number of potential deployment locations. Simulation results indicating safe sea conditions regarding both stability and structural integrity of CLOSEDFISHCAGE. (public)
Potential impact:
The closed fish cage system has been successfully validated according to the objectives set out in the work program for the project. During the project period, a prototype of 12 m in diameter, with closed canvas cage, inlet and outlet system, water supply from deep water (-60 m) with continuous monitoring of essential water quality parameters, such as: O2, ph and temperature, and alarm systems for O2 levels and pump failure. The system was also under continuous video surveillance, both above and below water. From September 2010 through June 2011 the system was tested in real conditions at the facilities of Norsk Havbrukssenter at Toft, Brønnøysund in Norway (see http://www.havbrukssenter.no/ online).Following that the system was towed out to a more location for intensified testing of waves and current exceeding the wave and current exposure that it experienced at Toft. The highest current speed we tested the prototype for was 1.0 m/s, and during this there was no distinct change in the shape of the canvas of the closed cage to be seen under water. We also recorded wave induced stresses in mooring lines for the closed cage over a short period of time, but unfortunately the weather did not permit us to test more exposed conditions than 0.5 m high waves. This however has been simulated by a created finite element model. We also kept some 100 salmon in the prototype closed cage for approximately 6 months as an indication test for growth, well fare and health performance for fish kept in a closed floating aquaculture system. The fish were taken at random from a neighbouring cage at Norsk Havbrukssenter, weighed, counted and checked for sea lice. When the fish at Toft were harvested from the traditional cages we found that the average weights of the fish in our prototype were exactly the same. On ending the validation trials, we also checked all the fish in the prototype for sea lice, and there was none to be found. In comparison the fish in the three other traditional cages at the same site had been treated against sea lice infestation three times. This is extremely promising, both from an environmental perspective and also a cost perspective, as in Norway alone one estimates sea lice related costs for the salmon industry to be in the order of EUR 1.25 million per year.
The closed cage is also more environmentally friendly compared to a traditional cage net as no antifouling is needed for treating cage surface against fouling growth. What fouling growth we got on our prototype could easily be removed using conventional non chemical washing methods. That has positive cost implications as during a normal production cycle at sea a traditional farm uses two cage nets pr cage pr cycle, one for the fry / smolts when the fish are put to sea, and another when changing to a net with a bigger mesh size when the fish gets bigger, both of these nets need to be treated with antifouling, this will not be the case for our closed cage. The cost of this anti fouling treatment is about EUR 12 500 per net, so a total of EUR 25 000 per cage pr farming cycle, so using our closed system would save EUR 25 000 per cage/cycle in addition to the environmental benefit of not having to use chemicals. Using such a closed system will also give the opportunity to collect faeces and excess feed from the production units by extracting it from the effluent water, which is difficult / impossible to do while using the traditional cage systems. We know that approximately 20 % of all eaten feed ends up as faeces, and that salmon, bass and bream have a similar FCR (feed conversion rate = kilo feed to produce kilo fish) of approximately 1.2 (1.2 kg feed to produce 1.0 kg fish). As a rough estimate we can say that feed passing through the cages without being eaten represents about 20 % of the total amount fed for salmon bass and bream. By looking at the total production of salmon in Norway, 1 000 000 tons, and the total production of bass and bream in the Mediterranean, 300 000 tons, and using an approximate FCR of 1.2 and a faeces contribution of 20 % of feed eaten by the fish for all three species we can estimate the total biological waste resulting from these farms. This gives a total production of 1 300 000 tons of fish, and a total use of fish feed of 1 560 000 tons. Following this argument the biological waste resulting from feed passing uneaten through the cages amounts to approximately 260 000 tons, and biological waste from faeces amounts to approximately 260 000 tons, yielding a total of approximately 520 000 tons of biological waste from these farms. This waste, or more correctly, resource could be collected and utilised, i.e. in the production of biogas when using a closed system such as CFC. The nature of the PVC canvas material of the closed cage will also prevent loss of fish to predators such as seals and otters, and it will also prevent juveniles of other species entering the cage and being trapped there when they grow. It will also eliminate the problem seen in bream and cod production where the fish bite through the cage nets. Jelly fish and harmful algae can no longer reach the fish, provided the inlet pipe(s) for the system the system are located sufficiently deep to avoid them.
We have done a comparison of cost/kg fish produced between the CFC system, Sea based cages, and a land based recirculation farm, with calculations based on production from a maximum standing stock of 780 tons of salmon. This is based on a common juvenile size of 0.1 kg and a harvest size of 5.1 kg, the production times are 22 months for sea cages, 18 for CFC and 12 for the land based. Densities of 25 kg/m3 for sea cages and CFC, and a density of 50 kg/m3 for the land based. The growth and cost figures are based on historical figures from the salmon farming industry at sea and Plastsveis' own experience with building land based farms. To simplify we have calculated the following cost items to be equal for the three systems, juveniles EUR 0.25 feed EUR 1.13 personnel EUR 0.13. The land based and CFC systems are dependant on adding O2, which adds EUR 0.19 to the total for the land based, and EUR 0.06 for the CFC. Energy we have set to EUR 0 per kg produced for sea cages as it's very low here, EUR 0.25 for land based, and EUR 0.06 for the CFC. For other costs, such as maintenance, boats, sea lice etc we have calculated it to be EUR 0.38 for the sea cages, and EUR 0.25 for both land based and CFC. The capital cost per kilo produced is EUR 0.19 for sea cages, EUR 2.38 for the land based, and EUR 0.71 for the CFC. This gives an estimate of total cost per kilo produced for the three systems of: EUR 2.1 sea cages, EUR 4.6 land based, and EUR 2.6 for the CFC. From this we can see that the sea based system is the cheapest, but the production cost in the CFC system is not more than EUR 0.5 higher, and almost half that of the land based system. This calculation is not taking into account the reduction in cost relating to fouling, and longer life span for the canvas of the closed cage compared to the nets of traditional cages. We have neither looked at possible cost reductions through utilisation of waste from the CFC system, as this is too early to properly quantify at this stage, but the potential is undoubtedly there.
The project has been thoroughly disseminated.
From when the first prototypes started to take shape, the work started to procure an R&D aquaculture licence for the CLOSEDFISHCAGE system. This was done through a number of meetings held with government bodies in order to promote the closed cage technology. Not only will such a licence allow us to validate the technology in a commercial scale, both biologically and technologically, but it will also function as the perfect sales front, where potential clients can come and see the system in operation, stocked with commercial densities of fish. The application was finally approved during the summer of 2011 and was given due to the results obtained and meetings held with government bodies in Norway during the CLOSEDFISHCAGE project period. This licence allows us to produce salmon, of up to 780 tons standing stock for a limited duration of time of 5 years.
In addition to disseminating the project to the authorities the project has been presented at 2 major exhibitions. Firstly, at AquaNor 2011 (see http://www.nor-fishing.no/index.php?page=aqua-nor-2011&hl=en_US for details), which is one of the biggest aquaculture exhibitions in the world. It was presented at the stands of Plast Sveis AS and Teknologisk Institutt as. This year the exhibition had a new attendance record, reflecting the positive market in the salmon industry over the last couple of years. More than 17 500 visitors from 61 nations came to AquaNor this year. This was 3500 more (+25 %) than during Aqua Nor 2009. The project was presented in a number of ways, by pamphlets, PowerPoint slide, video, pictures and a 3D printed model of a future full scale CFC farm. Secondly, at two technological exhibitions in Poland in the fall of 2011, one of which was the Industrial Technology, Science and Innovation Fair in Gdansk (see http://www.mtgsa.pl/title,TECHNICON_-_INNOVATION,pid,215,lang,2.html for details).
A project webpage has been established, where the public can read about the project:
http://www.closedfishcage.com
For further questions, please contact the coordinator of the project:
Mr Trond W. Johannessen
E-mail: twjohann@broadpark.no
Telephone: +47-905-89238
Website: http://www.plast-sveis.no/
The CLOSEDFISHCAGE project is a Seventh Framework Programme (FP7) project for 'Research for small and medium-sized enterprises (SMEs). It had an official start date of 1 September 2009, and has a complete duration of 24 months. The beneficiaries in the project are as follows:
- Plastsveis AS (SME and coordinator)
- Burashi Italia srl. (SME)
- Studsgaard AS (SME)
- SeaFarm Systems AS (SME)
- Cultivos Marinos Del Maresme SA (SME)
- Fjord Marin Holding ASA (OTH)
- Seawork (Scotland) Ltd (research and technology development (RTD) provider)
- Teknologisk Institutt AS (RTD)
- Politechnika Gdanska (RTD)
- Technologías Avanzadas Inspiralia SL (RTD)
Complete project description
CLOSEDFISHCAGE has focused on the development of a closed, escape proof, constant volume, sea-based cage for fish farming. Among the project's innovative elements are a very durable and flexible polymer plastic net pen, a predator guard, a control system, easy set-up and replacement of damaged cage parts and water treatment and control system. The technological solutions involved in the sea-based cage will preserve advantages of land-based fish farming while at the same time taking advantage of the cost efficiency of sea based fish farming.
The scientific research objectives and the specific technological objectives of the CLOSEDFISHCAGE project include:
- identify the physical, chemical, biological, regulatory aspects as well as good husbandry practices of sea based fish farming for target species and these aspects must be considered and linked to the development of closed cage and water treatment and control technologies to be developed in WP 2 and 3;
- identify and calculate key oceanographic data in order to model the environmental forces on the closed cage in order to ensure a design and technical solutions ensuring a constant water volume during different weather conditions;
- development of a closed cage with a volume change of less than 10 % during different weather conditions;
- development of a water treatment and control unit that will ensure optimal water quality with a change in oxygen level of less than 10 % compared to target setting during the day and a daily temperature fluctuation of less than 1.0 degrees Celsius.
Project context and objectives:
In our project we have had the objective to create a closed cage for sea based aquaculture in order to give the farmer more stable and better control of environmental parameters, such as O2, ph, and temperature, and to remove / reduce the risk of sea lice, harmful algae and jellyfish, in addition to reduce / remove the risk of predators getting into the farming units. The system will also have the possibility to clean all effluent water, similar to that of land based facilities.
Project results:
Description of the work performed and the main results achieved
The description of RTD work and main results are as follows:
WP1: Enhanced scientific understanding of biological, physical, operational and regulatory requirements for sea based fish farming
Objective:
To create a detailed understanding of which biological, physical, operational and regulatory requirements that need to be considered and applied for the technology to be developed in the proposed project, with respect to development of closed cage and water control system.
Results:
The main results from the work carried out in WP1 are presented in the following two reports:
- Report D1.1 - Reference document describing internal factors including biological, physical, chemical and operational criteria for consideration during development of closed cage and water control system.
This report identifies different fish species relevant for the project and the operational requirements including feeding, dead fish collection, cleaning of bio-fouling, water treatment, technical installations, monitoring and alarm systems, biomass monitoring, light manipulation, service and work vessels, grading and moving fish. (public)
- Report D1.2 - Reference document describing external factors including oceanographic conditions, regulatory requirements and existing infrastructures.
This report identifies oceanographic data including ocean current, wave height and salinity and temperature and existing infra-structures including surface cages - steel, surface cages polyethylene, submersible or semi-submersible cages and current trends in cage development. Not primarily in the description of work (DoW), but decided at the kick off meeting, evaluation of potential harmful organisms including harmful algae, harmful jellyfish and salmon-lice was included. Results have continuously been communicated to RTD partners and provide input to development in WP2 and WP3. The results are included in deliverable D1.1. (public)
WP2 Development of closed cage
Objective:
Based on specifications from WP1:
- develop a closed sea cage including material selection and design of closed net;
- build prototype;
- perform functional tests;
- optimisation of prototype;
- prepare for integration with water treatment and control system.
Results:
- Report D2.1 - Report describing the development of the prototype of closed cage for sea based fish farming
Present document describes first development phase of CLOSEDFISHCAGE project. In order to release a design compliant with such a wide range of constraints has been chosen a systematic approach. This approach is as follows:
(1) a definition of application driven requirements;
(2) fitting general requirements down to the level of prototype technical goals;
(3) study and definition of canvas optimal shape; and
(4) based in previously defined requirement baseline, as well work environment to perform canvas materials selection. The results are included in deliverable D2.1. (confidential)
- Report D2.2 - Prototype of the closed cage
This report covers the development effort carried out in order to establish the more rational canvas shape, as well the prediction of forces due to the effect of marine environment. In addition, the following criteria has been considered:
- stability of canvas shape;
- wetted exposed area;
- allowed membrane stress versus water head;
- effect of volume variation versus increase of water head.
Further there has been carried out two towing scale test, under different motion conditions. Obtained results allow us to predict the forces due to flow motion and inertial forces due to wave patterns. The results are included in deliverable D2.2. (confidential)
WP3 Development of water quality control system
Objective:
Based on specifications from WP1:
- development of water treatment and control technology in order to ensure good water quality including water intake at different water depths for variation in temperature, water inlet and outlet in closed cage and determine hydrodynamics in closed cage for homogenous water quality and sensor and control system;
- build prototype;
- perform functional tests;
- optimisation of prototype;
- prepare for integration with closed cage developed in WP2.
Results:
- Report D3.1 and 2 - Report describing the development of the prototype of water treatment and control system and set-up and result of functional testing of the water treatment and control system presenting both the theoretical work and the physical work, testing and integration that was done.
We have tested and validated the system at an end user locality (Norsk Havbrukssenter), and made further calculations regarding dimensioning of inlet and outlet pipes and flow, both with the dimensions that were used for the prototype and alternative dimensions and their resulting possible flows. In addition, we have made further calculations for scenarios using a commercial scale version (70 m circumference) of the CFC, which are also presented in D3.1 and 2. Included in D3.1 and 2 is also the technical description of the control system, relating to task 3.2 and data collected for water quality parameters by the control system. (confidential)
WP4: System integration and industrial validation
Objective:
Integration of the sub-parts produced in WP 2 and 3 in order to obtain a fully functional CLOSEDFISHCAGE system. Validation of the CLOSEDFISHCAGE system by demonstration of the fully integrated technology against the project objectives incl. benchmarking compared to existing technologies and economic analyses of cost effectiveness of new technology.
Results:
- Report D4.1 - Report describing the work performed in WP4, including the building of prototype(s), system integration, functional testing, benchmarking and analyses of cost efficiency.
The main focus for WP has been directed towards validation of fully functional prototype, which specifically means: a prototype capable of supporting the production of fish. The validation process was carried out over an extended period of 10 months. The report also includes the finite element model we developed and it has been upgraded in order to reproduce the Toft prototype's actual constructive solution, stresses and dynamic response. Using this upgraded numerical model we have run computer simulations for sea conditions corresponding to a number of potential deployment locations. Simulation results indicating safe sea conditions regarding both stability and structural integrity of CLOSEDFISHCAGE. (public)
Potential impact:
The closed fish cage system has been successfully validated according to the objectives set out in the work program for the project. During the project period, a prototype of 12 m in diameter, with closed canvas cage, inlet and outlet system, water supply from deep water (-60 m) with continuous monitoring of essential water quality parameters, such as: O2, ph and temperature, and alarm systems for O2 levels and pump failure. The system was also under continuous video surveillance, both above and below water. From September 2010 through June 2011 the system was tested in real conditions at the facilities of Norsk Havbrukssenter at Toft, Brønnøysund in Norway (see http://www.havbrukssenter.no/ online).Following that the system was towed out to a more location for intensified testing of waves and current exceeding the wave and current exposure that it experienced at Toft. The highest current speed we tested the prototype for was 1.0 m/s, and during this there was no distinct change in the shape of the canvas of the closed cage to be seen under water. We also recorded wave induced stresses in mooring lines for the closed cage over a short period of time, but unfortunately the weather did not permit us to test more exposed conditions than 0.5 m high waves. This however has been simulated by a created finite element model. We also kept some 100 salmon in the prototype closed cage for approximately 6 months as an indication test for growth, well fare and health performance for fish kept in a closed floating aquaculture system. The fish were taken at random from a neighbouring cage at Norsk Havbrukssenter, weighed, counted and checked for sea lice. When the fish at Toft were harvested from the traditional cages we found that the average weights of the fish in our prototype were exactly the same. On ending the validation trials, we also checked all the fish in the prototype for sea lice, and there was none to be found. In comparison the fish in the three other traditional cages at the same site had been treated against sea lice infestation three times. This is extremely promising, both from an environmental perspective and also a cost perspective, as in Norway alone one estimates sea lice related costs for the salmon industry to be in the order of EUR 1.25 million per year.
The closed cage is also more environmentally friendly compared to a traditional cage net as no antifouling is needed for treating cage surface against fouling growth. What fouling growth we got on our prototype could easily be removed using conventional non chemical washing methods. That has positive cost implications as during a normal production cycle at sea a traditional farm uses two cage nets pr cage pr cycle, one for the fry / smolts when the fish are put to sea, and another when changing to a net with a bigger mesh size when the fish gets bigger, both of these nets need to be treated with antifouling, this will not be the case for our closed cage. The cost of this anti fouling treatment is about EUR 12 500 per net, so a total of EUR 25 000 per cage pr farming cycle, so using our closed system would save EUR 25 000 per cage/cycle in addition to the environmental benefit of not having to use chemicals. Using such a closed system will also give the opportunity to collect faeces and excess feed from the production units by extracting it from the effluent water, which is difficult / impossible to do while using the traditional cage systems. We know that approximately 20 % of all eaten feed ends up as faeces, and that salmon, bass and bream have a similar FCR (feed conversion rate = kilo feed to produce kilo fish) of approximately 1.2 (1.2 kg feed to produce 1.0 kg fish). As a rough estimate we can say that feed passing through the cages without being eaten represents about 20 % of the total amount fed for salmon bass and bream. By looking at the total production of salmon in Norway, 1 000 000 tons, and the total production of bass and bream in the Mediterranean, 300 000 tons, and using an approximate FCR of 1.2 and a faeces contribution of 20 % of feed eaten by the fish for all three species we can estimate the total biological waste resulting from these farms. This gives a total production of 1 300 000 tons of fish, and a total use of fish feed of 1 560 000 tons. Following this argument the biological waste resulting from feed passing uneaten through the cages amounts to approximately 260 000 tons, and biological waste from faeces amounts to approximately 260 000 tons, yielding a total of approximately 520 000 tons of biological waste from these farms. This waste, or more correctly, resource could be collected and utilised, i.e. in the production of biogas when using a closed system such as CFC. The nature of the PVC canvas material of the closed cage will also prevent loss of fish to predators such as seals and otters, and it will also prevent juveniles of other species entering the cage and being trapped there when they grow. It will also eliminate the problem seen in bream and cod production where the fish bite through the cage nets. Jelly fish and harmful algae can no longer reach the fish, provided the inlet pipe(s) for the system the system are located sufficiently deep to avoid them.
We have done a comparison of cost/kg fish produced between the CFC system, Sea based cages, and a land based recirculation farm, with calculations based on production from a maximum standing stock of 780 tons of salmon. This is based on a common juvenile size of 0.1 kg and a harvest size of 5.1 kg, the production times are 22 months for sea cages, 18 for CFC and 12 for the land based. Densities of 25 kg/m3 for sea cages and CFC, and a density of 50 kg/m3 for the land based. The growth and cost figures are based on historical figures from the salmon farming industry at sea and Plastsveis' own experience with building land based farms. To simplify we have calculated the following cost items to be equal for the three systems, juveniles EUR 0.25 feed EUR 1.13 personnel EUR 0.13. The land based and CFC systems are dependant on adding O2, which adds EUR 0.19 to the total for the land based, and EUR 0.06 for the CFC. Energy we have set to EUR 0 per kg produced for sea cages as it's very low here, EUR 0.25 for land based, and EUR 0.06 for the CFC. For other costs, such as maintenance, boats, sea lice etc we have calculated it to be EUR 0.38 for the sea cages, and EUR 0.25 for both land based and CFC. The capital cost per kilo produced is EUR 0.19 for sea cages, EUR 2.38 for the land based, and EUR 0.71 for the CFC. This gives an estimate of total cost per kilo produced for the three systems of: EUR 2.1 sea cages, EUR 4.6 land based, and EUR 2.6 for the CFC. From this we can see that the sea based system is the cheapest, but the production cost in the CFC system is not more than EUR 0.5 higher, and almost half that of the land based system. This calculation is not taking into account the reduction in cost relating to fouling, and longer life span for the canvas of the closed cage compared to the nets of traditional cages. We have neither looked at possible cost reductions through utilisation of waste from the CFC system, as this is too early to properly quantify at this stage, but the potential is undoubtedly there.
The project has been thoroughly disseminated.
From when the first prototypes started to take shape, the work started to procure an R&D aquaculture licence for the CLOSEDFISHCAGE system. This was done through a number of meetings held with government bodies in order to promote the closed cage technology. Not only will such a licence allow us to validate the technology in a commercial scale, both biologically and technologically, but it will also function as the perfect sales front, where potential clients can come and see the system in operation, stocked with commercial densities of fish. The application was finally approved during the summer of 2011 and was given due to the results obtained and meetings held with government bodies in Norway during the CLOSEDFISHCAGE project period. This licence allows us to produce salmon, of up to 780 tons standing stock for a limited duration of time of 5 years.
In addition to disseminating the project to the authorities the project has been presented at 2 major exhibitions. Firstly, at AquaNor 2011 (see http://www.nor-fishing.no/index.php?page=aqua-nor-2011&hl=en_US for details), which is one of the biggest aquaculture exhibitions in the world. It was presented at the stands of Plast Sveis AS and Teknologisk Institutt as. This year the exhibition had a new attendance record, reflecting the positive market in the salmon industry over the last couple of years. More than 17 500 visitors from 61 nations came to AquaNor this year. This was 3500 more (+25 %) than during Aqua Nor 2009. The project was presented in a number of ways, by pamphlets, PowerPoint slide, video, pictures and a 3D printed model of a future full scale CFC farm. Secondly, at two technological exhibitions in Poland in the fall of 2011, one of which was the Industrial Technology, Science and Innovation Fair in Gdansk (see http://www.mtgsa.pl/title,TECHNICON_-_INNOVATION,pid,215,lang,2.html for details).
A project webpage has been established, where the public can read about the project:
http://www.closedfishcage.com
For further questions, please contact the coordinator of the project:
Mr Trond W. Johannessen
E-mail: twjohann@broadpark.no
Telephone: +47-905-89238
Website: http://www.plast-sveis.no/