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This page contains most of the deliverables from the project, sorted by type and date (newest at top).



Report (7)

Master thesis (6)

Journal publication (2)

Conf. paper (12)

Bachelor thesis (1)

Article (4)




Frontpage   Industry practices for sharing information in the Norwegian fisheries supply chains

By Strand, A.V., Thakur, M. (22.04.2022)

  • Many fishing vessels and fish processors are using electronic systems and capture data automatically. However, most information regarding quality is not shared in the supply chain.
  • Increasing the amount of data recorded and shared in the fisheries supply chain could increase quality of the seafood products as well as reducing the emissions.


Frontpage   Evaluation of PCM-CTES in maritime vessels

By Vingelsgård, E., Widell, K.N, Nordtvedt, T.S. (17.12.2021)

  • This report explores the possible benefits of peak shaving and energy saving using cold thermal energy storage.
  • Current available thermal energy storage solutions are evaluated, with a particular focus on ice slurry systems. Studies show these systems could reduce cooling time without significant damage to the fish's surface.
  • Also, some theoretical system configurations involving low-temperature phase change materials and cold recovery from liquid natural gas were discussed.


Frontpage   Equipment and systems onboard fishing vessels

By Widell, K.N, Tveit, G.M., Gabrielli, C., Cowan, E., Grimsmo, L., Svendsen, E.S. (02.09.2021)

  • The Norwegian fleet consists of fishing vessels ranging from small boats to large factory trawlers
  • Different fishing methods, gear and processing equipment is described
  • Energy saving methods are proposed and issues related to sustainability are described


Frontpage   Energy measurements onboard pelagic purse seiner

By Svendsen, E.S., Schei, M. (18.02.2021)

  • This report describes a research cruise carried out on a pelagic purse seiner during the autumn of 2020 on the North Sea, with an overall goal to perform an energy efficiency assessment of the onboard RSW system
  • Efficiency of the onboard cooling is heavily connected with operational modus of the vessel and RSW system, i.e. steaming to and from fishing grounds, pre-chilling of seawater, chilling of catch and maintenance chilling
  • Lowest efficiency was measured during maintenance chilling periods, which for this cruise was the periods with most operational hours. Efficiency measures should be targeted towards this mode.


Frontpage   Evaluation of possible synergy effects of processing and refrigeration onboard fishing vessels

By Widell, K.N., Saeed, M.Z., Gabrielii, C., Nordtvedt, T.S., Svendsen, E.S. (20.12.2020)

  • This report describes synergy effects of LNG driven vessels with onboard refrigeration and fish processing
  • The report cover topics such as conventional refrigeration technologies, utilizing free cooling from LNG driven vessels, use of cold thermal storages, fuels and propulsion technologies and heat recovery
  • The report concludes with a suggestion on the way forward


Frontpage   Alternative fuels and propulsion systems for fishing vessels

By Gabrielli, C., Jafarzadeh, S. (30.09.2020)

  • In Norway there is a development towards hybrid propulsion systems, including batteries. The use of LNG or biofuel as alternative fuel in combustion engines and the use of hydrogen or ammonia in fuel cells is feasible on a short- and medium term perspective, respectively.
  • The implementation of hybrid propulsion, and alternative fuels, enable fuel-efficient, low-emission and flexible operation. However, it implies challenges in relation to use of waste heat for covering thermal demands, and to proper sizing and operation of heating and cooling equipment.


Frontpage   Carbon footprint of fisheries - a review of standards, methods and tools

By Gabrielli, C., Jafarzadeh, S. (22.09.2020)

  • For captured seafood products the fishing vessel's fuel consumption is dominating the carbon footprint. The fuel intensity largely depends on fishing method, abundance of stocks, distance to fishing grounds, and type of on-board refrigeration and processing systems.
  • There are various methods, tools, guide-lines and certification schemes available for carbon footprint assessments of seafood. However, there is a need for further standardisation to enable accurate comparisons of various seafood products.


Master thesis

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Frontpage   Investigation and analysis of a CO2 heat pump chiller with novel two-stage evaporator

By Bengsch, J. (10.08.2022)

  • This thesis investigates the performance of a transcritical CO2 heat pump chiller with a novel two-stage evaporator for simulations heating and cooling which can be implemented e.g. hotels, commercial kitchens, fishing vessels, etc.
  • Simulation model of the two-stage evaporator (on stage gravity-fed, the other one ejector-fed) was developed using the language Modelica and the TIL-library
  • The simulation model was validated with the aid of measurement data from a test rig and model based investigations were carried out


Frontpage   Design and analysis of freeze-concentrator for processing of fish protein hydrolysate

By Khan, M.U. (20.06.2022)

  • Efficient utilization of rest raw materials from fish processing is a significant challenge for the fish processing industry and increasing the level of sustainability for food production. One way to utilize RRMs is through the processing of fish protein hydrolysates, with subsequent production of food-grade powders.
  • Drying raw fish protein hydrolysates is energy intensive, but freezing concentration provides high quality concentrate, energy efficiency (60% energy saving) and sustainability of the hydrolysate production.
  • The aim of this work was to develop simulations and lab scale setup for freeze concentration process for fish protein hydrolysates. Results includes the process of hydrolysation for 1 ton rest raw material, dynamic modelling of batch and steady state freeze concentration process and wash column.


Frontpage   Design of CO2 heat pump and refrigeration system for hydrolyzation & freeze concentration processes

By Leth-Olsen, J.M. (20.06.2022)

  • The processing of fish leaves a large amount of rest raw material (RRM) that is often only utilized for low-quality byproducts.
  • Utilizing the high nutritional values still contained in the RRM for the production of fish protein hydrolysates (FPH) using enzymatic hydrolysis can produce high-quality hydrolysate.
  • Freeze concentration is an energy-efficient and gentle manner to de-water the FPH prior to drying, better preserving the nutritional values and sensory characteristics of the product.
  • A simulation program has been written in Python to evaluate the heat transfer from the bulk hydrolysate to the refrigerant and determine the rate of ice formation in the contact freezing vessel, the impact of various factors such as vertical pipes vs coiled pipes, mass flux of refrigerant, uniform thermal gel layer between the pipe and vessel wall, diameter of the vessel and scrape velocity, and saturation temperature of the refrigerant were also investigated.


Frontpage   Sustainable production of fish protein hydrolysates: Overall system architecture and footprint

By Sherman, P.K. (20.06.2022)

  • There is a growing interest to use the fish rest raw materials (RRM) in a more economical manner. Fish Protein Hydrolysates (FPH) produced from RRM have increasing application in the food and medicine industry
  • FPH production is energy intensive and sustainability of this process requires optimization, which also would reduce the greenhouse gas emission from the process
  • The energy study indicates that energy reduction of 60% is possible producing in an energy efficient manner


Frontpage   Energy efficient CO2 refrigeration units for fishing vessels

By Semaev, P. (20.06.2021)

  • This thesis describes the architecture and performance of a prototype industrial CO2 transcritical system for refrigerated seawater.
  • The CO2 system will cover cooling demands for air conditioning, refrigerated seawater, and low-temperature freezing.
  • Five simulation models for the CO2 system were developed using Engineering Equation Solver (EES) and Dymola/Modelica.


Frontpage   Energy efficient and climate friendly cooling, freezing and heating onboard fishing vessels

By Saeed, M.Z. (01.06.2020)

  • The fishing fleet of Norway consists of different types of vessels, ranging from small boats to large fish factories, with a total number of more than 6000 vessels. All vessels have methods for keeping the fish cold to preserve fish quality and shelf life
  • Fishing vessels are in a transition from heavy hydrocarbon fuels and synthetic refrigerants to environment-friendly solutions. Liquified natural gas (LNG) as fuel is one of the potential solutions as it emits 90% less NOx, 24% less CO2 and almost no SOx compared to existing fuels.
  • The master thesis work has developed a simulation platform to be able to analyse the impact and performance of different energy system configurations onboard with natural refrigerant CO2 and LNG as fuel


Journal publication

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Frontpage   Overview of the development and status of carbon dioxide (R-744) refrigeration systems onboard fishing vessels

By Söylemez, E., Widell, K.N, Gabrielli, C., Ladam, Y., Lund, T., Hafner, A. (01.05.2022)

  • On a global scale, the climate-harmful refrigerant R22 is the most common amongst fishing vessels
  • The natural refrigerant CO2/R744 is becoming a viable option and there are currently major developments in CO2 refrigeration technology that are widening the potential applications for such systems
  • This paper provides a review of these recent developments, including descriptions of the commonly used cooling/freezing methods and current status of available R744 refrigeration technology onboard fishing vessels


Frontpage   An experimental study of an ejector-boosted transcritical R744 refrigeration system including an exergy analysis

By Elbarghthi, A., Hafner, A., Banasiak, K., Dvorak, V. (15.06.2021)

  • The study examines the use of an ejector, a device that allows for recovering some of the expansion work in cooling systems, in a R744 transcritical ejector cooling system
  • The experiment was conducted on a commercial ejector cartridge, and the impact of different operating conditions on the ejector's performance were evaluated
  • The study found that the ejector was able to recover up to 36.9% of the available work rate, provide a maximum pressure lift of 9.51 bar, and deliver a maximum exergy efficiency of 23% when working at higher motive nozzle flow temperatures and lower exergy destruction.


Conf. paper

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Frontpage   Evaluation of cold thermal energy storage in fishing vessels

By Vingelsgård, E., Svendsen, E.S., Widell, K.N, Nordtvedt, T.S. (13.06.2022)

  • Fishing vessels and fish transporting well-boats have varying cooling demands depending on the operational mode
  • Cold thermal energy storage (CTES) can potenially be used for peak shaving and energy saving in these vessels, with a focus on compact and efficient systems
  • In this study, theoretical calculations were conducted to find the requirements of an ice slurry system according to the reference conditions of the studied case, utilizing thermodynamic properties of ice and fish


Frontpage   Experimental investigation on integrated two-stage evaporators for CO2 heat-pump chillers

By Hafner, A., Hazarika, M.M., Lechi, F., Zorzin, A., Pardiãs, A.A., Banasiak, K. (13.06.2022)

  • A novel compact two-stage evaporator, i.e. evaporator with one gravity-fed loop and one ejector-assisted circulation loop, is explored in this experimental study
  • Compared to previous heat exchanger models this design allows for less connection work and required space due to the internal connection of loops
  • The experimental campaign proofed that en ejector integration enables the two-stage evaporation configuration, which significantly elevates compressor suction and overall system performance


Frontpage   Integration of gravity-fed evaporators in CO2 based refrigeration systems

By Hazarika, M.M., Bengsch, J., Hafsås, J., Hafner, A., Svendsen, E.S., Ye, Z. (13.06.2022)

  • A model of a gravity-fed evaporator for CO2 based heat-pump chillers is studied in this paper
  • Appropriate equations are used and implemented in Modelica to develop a simulation model for this novel heat exchanger design
  • Loop dimensions are critical to the performance; simulations are carried out to predict the optimum dimensions to achieve the optimum circulation rate in the loop


Frontpage   Industry practices for sharing sustainability information in the Norwegian seafood supply chains

By Strand, A.V., Thakur, M., Widell, K.N, Gabrielli, C. (11.04.2022)

  • Sustainability and traceability of food products have received increased attention due to food safety, consumer demand on knowledge of the origin of their food and reducing food fraud.
  • Most Norwegian fishing vessels capture detailed data on the catch and quality of fish electronically. This information is automatically reported to the authorities while most information regarding the quality and sustainability is not communicated further down the supply chain.
  • Significant data gaps include information on fuel and energy consumption, as well as detailed data on the transport routes and modes used


Frontpage   Application Of Refrigeration Technologies For Energy Efficient Production Of Fish Protein Hydrolysates

By Sherman, P.K., Tolstorebrov, I., Widell, K.N, Hafner, A., Nordtvedt, T.S. (11.04.2022)

  • Fish protein hydrolysate (FPH) is an efficient and sustainable way to recover valuable nutrients from fish remaining materials and has a widespread application.
  • However, the production of FPH demands intensive heating and cooling loads in the temperature range between 0 and 90 ⁰C, and stabilization using conventional moisture removal techniques like spray drying and evaporators is energy intensive due to low solid content.
  • This study investigates the use of refrigeration technologies and heat pumps to determine sustainable and energy efficient methods for processing and stabilization of FPH. Techniques such as freeze concentration, vacuum-concentration and freeze-drying were investigated in combination with energy recovery at high temperatures to compare energy savings of different production lines.


Frontpage   Modelling Of Crystallization During Freeze-Concentration Of Hydrolysates

By Khan, M.U., Tolstorebrov, I., Widell, K.N, Hafner, A., Nordtvedt, T.S. (11.04.2022)

  • Dewatering of fish protein hydrolysates is energy intensive process
  • Freeze concentration is an energy efficient solution which provides high quality of concentrate
  • Crystallization of water in fish protein hydrolysates and separation of ice from concentrate were modelled in Modelica and MATLAB, and validated against experimental campaigns and literature review


Frontpage   Energy consumption of ammonia refrigeration system on board a fishing vessel

By Svendsen, E.S., Widell, K.N, Nordtvedt, T.S., Jafarzadeh, S., Gabrielli, C. (16.09.2021)

  • This paper presents energy measurement results from a research cruise conducted during autumn 2020 on a combined purse seiner/pelagic trawler.
  • The vessel's refrigeration system was instrumented with sensors logging the electrical input to frequency converters (compressors and seawater pumps) and temperatures on the RSW side, while the vessels mode of operation and fuel consumption was logged on a regular basis during the cruise.
  • The results provide insight on the vessel's energy flow, performance of the refrigeration system and fuel intensity of the fishing operation, which gives valuable input for design of efficiency measures.


Frontpage   Simulation of a carbon dioxide (R-744) refrigeration system for fishing vessel

By Semaev, P., Söylemez, E., Tolstorebrov, I., Hafner, A., Widell, K.N., Lund, T., Øy, J., Urke, J.P. (16.09.2021)

  • This is a short version of the master thesis by Pavel, with selected results
  • The paper describes the architecture of a prototype industrial CO2 trans-critical system for refrigerated seawater (RSW) production for either fishing vessels or land-based process plants. The refrigeration system was designed to cover the cooling demands of RSW (up to 450 kW), air-conditioning (up to 170 kW), and freezing equipment (up to 82 kW at -25 °C).
  • Four system design cases were evaluated: one stage compression, two-stage expansion with auxiliary compressor, three-stage expansion with parallel compressors, and two-stage expansion supported by an ejector
  • The optimum high side pressure level and the effectiveness of an internal heat exchanger were investigated to optimize the four system designs concerning capacity, seawater temperature, and COP.


Frontpage   Thermal Energy Storage with PCM for Refrigerated Sea Water System of Fishing Vessels

By Saeed, M.Z., Widell, K.N, Hafner, A., Svendsen, E.S., Nordtvedt, T.S. (01.09.2021)

  • Four different scenarios were investigated, including ice in tanks, two design modifications in chilling tanks, and plug-in thermal storage. The use of ice in chilling tanks as cold thermal storage was assessed since it can assist RSW system and reduce total chilling time. This was done by the addition of 5 m3 ice, which resulted in a reduced cooling time of 30 minutes.
  • Suggestions for design modifications in chilling tanks were also introduced to assess the potential of built-in thermal storage. A concept for plug-in thermal storage was also designed, employing a phase change material of 4 °C. Results showed that 1 m3 thermal energy storage could provide an average of 30 kWh for chilling fish during peak load.


Frontpage   Integrated thermal storage and heat recovery of the CO2 refrigeration system for fishing vessels

By Saeed, M.Z., Widell, K.N, Hafner, A., Nordtvedt, T.S., Svendsen, E.S. (01.12.2020)

  • This paper is a cold thermal storage explored to assist the refrigeration system at peak freezing loads. The integrated thermal storage is a Co2 based system with a capacity of 50 kWh. The system reduces the peak freezing time from 10 to 8 minutes, with 28 peaks per day, giving the system an additional production capacity of 56 minutes per day.
  • Heat recovery from the gas cooler was used to fish oil production
  • Dynamic simulations were modelled in Dymola with libraries from TIL.


Frontpage   Cryogenic cold utilization and system integration possibilities for LNG-driven fishing vessels

By Saeed, M.Z., Widell, K.N, Hafner, A., Nordtvedt, T.S., Svendsen, E.S. (29.08.2020)

  • The saturation temperature of LNG at 1 bar is -162 °C, and during regasification could the cold in the LNG be used to assist the refrigeration system.
  • This paper discusses several methods to utilize the cold, i.e. sub-cooling of refrigerant, direct chilling of fish tank, and thermal storage
  • A steady-state thermodynamic analysis of the LNG cold recovery was performed on Aspen HYSYS V10.


Frontpage   Refrigeration and sustainability in the seafood cold chain.

By Nordtvedt, T.S., Widell, K.N (29.08.2020)

  • The sustainability in the seafood is discussed concerning the environmental effects above the ocean surface
  • Parts of the cold chain are explored, such as refrigeration after harvest at sea, seafood farming, seafood processing, and transport.
  • The sustainability of the seafood value chain is compared through the product's carbon footprint.


Bachelor thesis

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Frontpage   Bærekraftig produksjon av hydrolysat

By Knudsen, N.B., Raphaug, I.H., Bardal, A. (20.05.2022)

  • Hensikten med denne oppgaven var å se på hvordan man kan videreforedle hydrolysat av fiskerestråstoff på en måte som øker kvalitet og kommersiell verdi, i tilleg til å besvare problemer når det gjelder effektiv og bærekraftig bruk av marine ressurser i produksjon og konsum
  • Det ble gjennomført 6 ulike prosesser innen separering, oppkonsentrering og tørking av hydrolysatprøver, inkl. analyser for å bestemme kvalitetsparametre
  • Ut fra valgte kvalitetskriterier (farge, protein- og saltsammensetning) var de beste resultatene oppnådd med en trestegprosess bestående av mikrofiltrering, oppkonsentrert med nanofiltrering og frysetørking



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Frontpage   Kulde nr 5 2022 - Articles covering CoolFish-meeting in Ålesund (4 stories)

By Wad, J. (31.05.2022)

  • Fagbladet Kulde var tilstede og dekket CoolFish-møte i Ålesund september 2022
  • 4 Artikler ble skrevet om møtet
  • Presentasjoner fra møtet er tilgjengelig under Workshops


Frontpage   Mer klimavennlig sjømatproduksjon

By Widell, K.N, Jafarzadeh, S. (02.08.2020)

  • Det blir mer og mer viktig å finne løsninger for å redusere klimagassutslipp
  • En studie ledet av SINTEF Ocean viste at fiskerisektoren har klimagassutslipp melloom 2-24% av utslippet til storfeproduksjon
  • For å gjøre sjømatproduksjonen mer klimavennlig er der behov for å finne tiltak som kan redusere drivstofforbruk og utslipp fra fiskefartøy


Frontpage   Mer klimavennlig sjømatproduksjon

By Widell, K.N, Jafarzadeh, S. (01.08.2020)

  • Det blir mer og mer viktig å finne løsninger for å redusere klimagassutslipp
  • En studie ledet av SINTEF Ocean viste at fiskerisektoren har klimagassutslipp melloom 2-24% av utslippet til storfeproduksjon
  • For å gjøre sjømatproduksjonen mer klimavennlig er der behov for å finne tiltak som kan redusere drivstofforbruk og utslipp fra fiskefartøy


Frontpage   Skal bruke 15 millioner på å utvikle nye, klimavennlige kjølesystemer i fiskebåter

By Widell, K.N (05.11.2019)

  • Nyhetsartikkel i Tekfisk (Fiskeribladet) om forskningsprosjektet CoolFish