Modeling of energy intensity in aquaculture: Future energy use of global aquaculture

Global aquaculture production has increased rapidly over the past decades; however, aquaculture systems have become more energy intensive, mainly relying on non-renewable sources. Increasing energy prices and energy cost fluctuation could make aquaculture industry vulnerable, and eventually, it would reduce food security at the local, regional, and global level. Therefore, understanding and mitigating the energy use in aquaculture is important for the sector to grow in a sustainable manner. This study aims to understand the energy intensity of various forms of aquaculture. The energy intensity of aquaculture was investigated using a modeling approach with consideration of culture species, culture system intensity, culture technology, and climatic condition. The established energy intensity model was used to estimate the energy use of current global aquaculture, and to explore possible strategies for the expansion of future global aquaculture in an energy efficient way with various growth and climate change scenarios. Results showed that a significant amount of energy use (about 100 TJ/ yr) could be saved with a selective extensification of aquaculture (i.e., the increase in extensive culture systems in developing countries for all trophic levels of species, along with the increase in intensive marinebased culture systems in developed countries only for low trophic level species) compared to the baseline. Also, as warm climates are more dominant in major aquaculture producing countries by 2025, the energy intensity of future global aquaculture would be reduced.