Carbon Footprint in Aquaculture
1. Overview
The carbon footprint (CFP) of aquaculture represents the total amount of greenhouse gas (GHG) emissions generated directly and indirectly throughout the entire life cycle of aquaculture products (International Organization for Standardization [ISO], 2018). It includes emissions from feed production, energy consumption, transportation, water use, infrastructure construction, and waste treatment, quantified in carbon dioxide equivalents (CO₂-eq).
The CFP assessment follows the Life Cycle Assessment (LCA) approach defined by ISO 14040 and ISO 14044, and is standardized for product-level evaluations by ISO 14067:2018 – Greenhouse Gases: Carbon Footprint of Products. Complementary methodologies such as PAS 2050 and the GHG Protocol Product Standard provide additional guidelines for data collection, emission factor selection, and reporting boundaries.
2.Methodological Framework
The carbon footprint analysis in aquaculture typically proceeds through four main stages:
- Goal and Scope Definition: Establishing the purpose of the study, the functional unit (usually 1 kg or 1 ton of aquaculture product), and the system boundaries (cradle-to-grave, cradle-to-gate, or gate-to-gate).
- Inventory Analysis: Collecting activity data for inputs such as feed ingredients, energy use, water consumption, and chemical applications.
- Impact Assessment: Converting emissions into CO₂-equivalents using Global Warming Potential (GWP100) factors published by the Intergovernmental Panel on Climate Change (IPCC).
- Interpretation: Identifying critical emission sources and potential mitigation measures for improved environmental performance.
3.Main Emission Sources in Aquaculture
Among all production inputs, feed manufacturing and energy consumption are the dominant contributors to aquaculture’s carbon footprint.
- Feed-related emissions:
The production and processing of key ingredients such as soybean meal, fish meal, and wheat flour contribute significantly to GHG emissions. Feed production alone may account for over 50% of the total carbon footprint in shrimp and fish farming systems (Rong et al., 2025). For example, 1 ton of shrimp feed production can emit more than 900 kg CO₂-eq from soybean meal and nearly 800 kg CO₂-eq from fish meal. - Energy use:
Electricity is required for aeration, heating, pumping, water circulation, lighting, and processing. In Recirculating Aquaculture Systems (RAS), where continuous water treatment and recirculation are needed, energy demand can reach 2.9–81.5 kWh per kilogram of fish depending on production intensity (Badiola et al., 2018). In a shrimp pond system, energy use alone contributed to more than half of the total carbon footprint (Rong et al., 2025). - Other factors:
Water use, transportation of materials and products, and post-harvest processing (including packaging and waste treatment) also add to total emissions, though generally to a lesser extent.
4.System Boundaries and Comparative Analysis
Studies show that the carbon footprint varies significantly depending on system design and energy source.
- In a Life Cycle Assessment (LCA) of shrimp production, total emissions reached approximately 6.9 kg CO₂-eq per kilogram of shrimp, with the aquaculture phase accounting for nearly 46% of the total, primarily due to feed use and electricity consumption (Chang et al., 2017).
- Comparative analyses show that RAS-based salmon production powered by fossil fuels produces around 7.01 tons CO₂-eq per ton of fish, almost twice the footprint of open cage systems (3.39 t CO₂-eq/t) (Liu et al., 2016). When powered by renewable energy, RAS emissions can be reduced to around 3.7 t CO₂-eq/t.
- Pond-based systems in Asia, which rely less on mechanical aeration and more on natural processes, typically emit 1.4–1.8 kg CO₂-eq per kg of fish, particularly when land-use change impacts are excluded (Robb et al., 2017).
5.Strategies for Reducing Carbon Footprint
To enhance sustainability and align aquaculture with climate goals, emission reduction strategies should focus on:
- Energy transition: Shifting from fossil fuels to renewable energy sources such as solar, wind, or hydroelectric power, particularly in energy-intensive RAS operations.
- Feed optimization: Improving feed conversion ratios (FCR), using alternative protein sources (e.g., microalgae, insect meal, agricultural by-products), and sourcing ingredients locally to reduce transport emissions.
- Waste management and nutrient recovery: Implementing integrated systems such as aquaponics or biofloc technology (BFT) to recycle nutrients and minimize effluents.
- Technology and process innovations: Using smart monitoring systems, efficient pumps, variable-speed drives, and automation to reduce energy demand.
6.Concluding Remarks
Assessing the carbon footprint of aquaculture systems provides essential insight into their environmental performance and helps identify hotspots of GHG emissions. It supports the transition toward low-carbon and circular aquaculture, consistent with the European Green Deal and UN Sustainable Development Goals (SDGs), particularly SDG 13 (Climate Action) and SDG 14 (Life Below Water).
Ultimately, reducing the carbon footprint in aquaculture requires a systemic approach, integrating sustainable feed production, renewable energy use, and effective waste valorization to ensure that future aquaculture development remains both environmentally responsible and economically viable.
References
Badiola, M., Basurko, O. C., Piedrahita, R., Hundley, P., & Mendiola, D. (2018). Energy use in Recirculating Aquaculture Systems (RAS): A review. Aquacultural Engineering, 81, 57–70. https://doi.org/10.1016/J.AQUAENG.2018.03.003
Chang, C.-C., Chang, K.-C., Lin, W.-C., & Wu, M.-H. (2017). Carbon footprint analysis in the aquaculture industry: Assessment of an ecological shrimp farm. Journal of Cleaner Production,168,1101-1107.
International Organization for Standardization. (2006a). Environmental management — Life cycle assessment — Principles and framework (ISO 14040:2006). ISO. https://www.iso.org/obp/ui/#iso:std:iso:14040:ed-2:v1:en
International Organization for Standardization. (2006b). Environmental management — Life cycle assessment — Requirements and guidelines (ISO 14044:2006). ISO.
International Organization for Standardization. (2018). Greenhouse gases — Carbon footprint of products — Requirements and guidelines for quantification (ISO 14067:2018). ISO. https://www.iso.org/obp/ui/#iso:std:iso:14067:ed-1:v1:en
Liu, Y., Rosten, T.W., Henriksen, K., Hognes, E.S., Summerfelt, S., Vinci, B., 2016. Comparative economic performance and carbon footprint of two farming models for producing Atlantic salmon (Salmo salar): land-based Closed containment system in freshwater and open net pen in seawater. Aquacult. Eng.71, 1-12.
Robb, D.H.F., MacLeod, M., Hasan, M.R., Soto, D., 2017. Greenhouse Gas Emissions from Aquaculture: A Life Cycle Assessment of Three Asian Systems. FAO Fisheries and Aquaculture Technical Paper No. 609, Rome.
Rong, F., Liu, H., Zhu, J., Qin, G. (2025). Carbon footprint of shrimp (Litopenaeus vannamei) cultured in recirculating aquaculture systems (RAS) in China. Journal of Cleaner Production, 510, 145606.
World Resources Institute, & World Business Council for Sustainable Development. (2011). GHG Protocol Product Life Cycle Accounting and Reporting Standard. Washington, DC: WRI and WBCSD.
WKC Group. (2023). PAS 2050: Assessment of the life cycle greenhouse gas emissions of goods and services. WKC Group. https://www.wkcgroup.com/wp-content/uploads/2023/02/PAS-2050-Assessment-of-the-life-cycle-greenhouse-gas-emissions-of-goods-and-services.pdf