ShareMarshall Islands: ice slurry system in tuna processing plant can reduce energy consumption by up to 40%
According to case study reported by FAO in a key tuna processing facility in Majuro, Marshall Islands, the adoption of a high-efficiency slurry ice system can reduce energy consumption by up to 40% and cut diesel use by 21,870 litres/year.
Due to the lack of adequate refrigeration systems, the global fishing sector faces the dual challenge of significant food loss and detrimental environmental impact of high-GWP refrigerants used in aging systems [1].
Transitioning to environmentally friendly and energy-efficient refrigeration technologies is therefore imperative, especially in some Article 5 island countries, where economy depends substantially on the fisheries sector.
The Food and Agriculture Organization (FAO) reported a case study of a modernisation plan to enhance efficiency, sustainability, and operational resilience in a key tuna processing facility in Majuro, Marshall Islands [2]. The study was conducted as part of the FISH4ACP initiative for more sustainable fisheries and aquaculture value chains in Africa, the Caribbean and the Pacific.
The facility, Marshall Islands Fishing Venture, Inc., is a critical stakeholder of the in the Marshall Islands' tuna economic sector and specialises in the processing, cold storage, and export of tuna.
Refrigeration and ice production
According to the assessment report, traditional ice-making systems at the facility, while effective, required significant energy inputs and did not provide optimal chilling efficiency. The existing condensers and compressors operated under constant load, with some units nearing the end of their operational lifespan.
Adopting a slurry ice system was expected to enhance cooling rates, improve product quality, and reduce overall energy consumption, ensuring a more sustainable and cost-effective processing operation.
It was estimated that a high-efficiency slurry ice system would reduce energy consumption by up to 40% and cut diesel use by 21,870 litres/year, alongside refrigeration and compressor upgrades, water management improvements, and a phased transition to a purpose-built facility.
Upgrades would lower CO₂ emissions by approximately 320 metric tonnes/year, improve product quality, and streamline workflows.
Financial returns and operational savings
The facility relied entirely on diesel generators for its energy needs, which introduces cost volatility linked to global fuel prices.
Despite high capital investment, the transition to slurry ice system is expected to yield over USD 40 000 in annual savings in fuel, labour, and maintenance.
In addition, upgrades to more efficient components can reduce system load, thereby lowering maintenance costs and increasing the lifespan of refrigeration equipment.
For more information, the complete report in available in open access on the FAO website.
Sources
[1] IIR and UNEP (2025). Cold Chain Technology Brief: Fishing Vessel Applications. International Institute of Refrigeration (IIR) and United Nations Environment Programme (UNEP), Paris. http://dx.doi.org/10.18462/unep.iir.coldchainbrief.fishing.10.2025
[2] Walsh, B.M. 2025. Marshall Islands Tuna Purse Seine Fishery Energy and Water Assessment Marshall Islands Fishing Venture Inc., Rome, FAO. https://openknowledge.fao.org/items/4f72c7e4-82cf-4839-b7b4-7cc26695d05b
[MB1]Add link https://www.fao.org/fish4acp/en