Scots pelagic fishers committed to reducing carbon emissions
In this article, Ian Gatt CBE, chief executive Scottish Pelagic Fishermen’s Association, outlines some of the work by the Scottish pelagic industry in reducing carbon emissions
Whilst it is early days yet, the new Labour Government has been sending the right signals about its recognition of the importance of national food security – and with the UK having ambitions to reach Net Zero greenhouse gas emissions by 2050, there is a need to use innovation and modern-thinking to ensure the right balance is achieved between food supply and carbon footprint.
The Intergovernmental Panel on Climate Change estimates that food production accounts for between 21-37% of global human carbon emissions. Whilst only four per cent of this figure is attributable to wild capture fisheries, it is important that all industries review their practices and look for potential areas for improvement.
This is already work in progress for the Scottish pelagic fishing sector, and indeed we are in the fortuitous position of being ahead of the game when it comes to carbon footprint.
The pelagic sector in Scotland has supported scientific research in this field, which has helped the industry understand how the carbon footprint of pelagic fish compares to other food products, and where improvements could potentially be made. The importance of pelagic fish to national food supply cannot be over-stated, given that landings from the sector make up over 50% of all sea fish landings by weight.
The results of such research has shown that one kilogram of pelagic fish caught by the Scottish fleet had a carbon footprint of 0.452 kg CO2 equivalent. In comparison, the global average carbon footprint for one kilogram of beef is 36 kg CO2 equivalent. In short, the findings revealed that the pelagic sector’s carbon footprint is considerably lower than terrestrial animal source proteins and is more comparable to vegan alternatives.
The Cefas report, ‘Carbon emissions in UK fisheries: recent trends, current levels, and pathways to Net Zero’, published in 2022 noted that while both the quantity and especially the value of pelagic landings increased between 2005–2009 and 2015–2019 (by +9% and +58% respectively), all metrics related with emission levels decreased for the UK pelagic trawler fleet: total emissions (–26%), per-vessel emissions (–13%), per-quantity emissions (–32%) and per-value emissions (–53%).
The report added that while pelagic trawlers have the highest emissions levels per-vessel of all vessels in the UK fleet, they have the lowest emissions per-quantity landed. Per-quantity and per-value, the pelagic fleet has made the greatest reductions among all nine main fleet segments over the decade examined in the report.
So far, so good, but the Scottish pelagic sector is not content to rest on its laurels and is working towards lowering its carbon footprint even further. One obvious area is engine efficiency and fuel consumption, as the research study mentioned above established that fuel usage amounted to 96% of the carbon emissions. To this end, the pelagic fleet is continually renewing its vessels to ensure the most modern designs and fuel-efficient engines. The pace of such renewal is a truly remarkable and is testament to the dynamism of the local fishing families who own and operate these vessels. They are committed to a sustainable future where environmental responsibility is a guiding principle.
According to leading engine manufacturer, Wärtsilä, the state-of-the-art engines in such boats exhibit exceptional fuel efficiency made possible through the use of new technologies, such as two-stage turbocharging, high-pressure fuel injection systems and adjustable valve actuations, all working in combination with next-generation engine control systems. Combustion quality, engine parameters, heat and flow loss prevention, and internal friction are among the issues exhaustively explored and addressed in these engines. Adjustable inlet valve timing, combined with electronic ignition timing, result in fewer unburned hydrocarbons, and therefore vastly improved efficiency and lower emissions, irrespective of the load.
Ally West, co-skipper of the Resolute and vice-chairman of the Scottish Pelagic Fishermen’s Association tells me that gearboxes also play an important role. He says: “Some vessels, including the Resolute have a two-step gearbox installed, which slows down the speed in which the propeller turns through the water, which saves a lot of fuel as it prevents the engine from overworking.
“We use it when we are searching for fish and when we are heading back to shore to offload our fish. On average, we reckon it saves us 25/30% of fuel for doing the same speed of 11-12 knots.”
Furthermore, the latest vessels are also using Selective Catalytic Reduction (SCR) technology, which dramatically reduces the level of nitrogen oxide in the exhaust gas from the engine, a chemical compound that contributes to air pollution and acid rain.
Biofuels and other alternative fuels such as liquefied natural gas, hydrogen or ammonia form other potential pathways in the future for carbon emission reductions, as well electric/hybrid vessels. All this, combined, with new ship designs with optimised hull lines, as well as innovations in fishing gear design will aid the process of meeting Net Zero targets.
With the FAO estimating the world population will reach 9.7 billion by 2050, there is a more pressing need than ever for sustainable low carbon footprint production. Due to the rising global population, to maintain through to 2050 aquatic food supplies at current per capita consumption would require an increase in production of 22 percent, which further underlines the need for production efficiencies.
The Scottish pelagic sector has a key role to play in that process, sustainably harvesting a renewable resource and contributing both to national and international food security whilst keeping carbon emissions down.
