The national and international fishing industry faces major challenges to be able to contribute in reducing greenhouse gas emissions. To cope with this, new fuels and engine technologies for propulsion of fishing vessels are under rapid development. On board there are also energy-consuming equipment to keep the catch refrigerated and systems for producing hot water. The development of new propulsion technology alters the premises for thermal energy demand and production, thereby directly influencing the design of the next generation of onboard refrigeration systems. This project aims to contribute in the development of these next generation refrigeration systems and doing so in an energy efficient and climate friendly fashion by utilizing the opportunities provided by new propulsion technology and employing natural refrigerants.
There are two ways a refrigeration plant can contribute to global warming:
- Primary energy use (electricity)
- Leakage of refrigerants with high GWP (global warming potential)
The onboard electricity is often generated by fossil-fuelled generators, implying that a reduction in a refrigeration plants energy usage is not only wise in economic terms, but also lowers the carbon footprint. Another source which contributes to global warming is refrigerant leakage, which due to the rough conditions at sea tends to be relatively higher than for a land-based plant. A transition from synthetic refrigerants with high GWP-values towards natural refrigerants which have no negative environmental impact is therefore essential. In addition, experience from the ongoing innovation of refrigeration systems employing natural refrigerants indicates that these are a good match for chilling and freezing of fish in terms of quality!
New technology alters the premises
New propulsion technology and new fuels alters the premises for thermal energy production and demand onboard fishing vessels. For instance, an electricity driven vessel doesn’t provide the same heat recovery possibility as for fossil-fuelled vessels, meaning that next-gen energy system must cover a larger share of hot thermal demands. Former research has generated a broad knowledge and expertise in this kind of issue and has ultimately led to a successful introduction of integrated cooling-and-heating systems using CO2 as refrigerant for the Nordic supermarket sector. Applying and further expanding upon this knowledge is within the scope of CoolFish, by adapting the technology to the operational conditions of fishing vessels.
LNG is emerging as fuel of choice for more and more vessels. This introduces the possibility to cover a significant portion of the cooling and freezing demand for fish preservation by utilizing the surplus cold from the LNG system. Thermal energy storage is another interesting feature, offsetting the mismatch between energy production and demand, which might be a good fit for systems onboard fishing vessels. All these possibilities will be investigated within the CoolFish project.
The project is being led by SINTEF Ocean with research partners SINTEF Energy Research and NTNU, and with industry partners MMC First Process, Bluewild, Selvåg Senior/Sørheim Holding, Øyangen, GASNOR, Danfoss, Perfect Temperature Group and Isotherm Inc. The reference group consists of International Institute of Refrigeration, London South Bank University and Johnson Controls.