integrated Seawater aquaculture/agriculture systems for bioenergy production in the Middle East: feasibilty and Life Cycle analysis

J. Jed Brown*, Brian Warshay, Sgouris Sgouridis
 
 
Center for Sustainable Development, College of Arts and Sciences, Qatar University
P.O. Box 2713, Doha, Qatar
Mob: (+974) 3045 3776
Email: jbrown@qu.edu.qa

The arid Middle East is beset by a lack of freshwater resources, which makes most conventional freshwater-based agriculture and aquaculture unsustainable. Many countries in the Gulf, however, have large amounts of groundwater that is too saline for conventional agriculture, in addition to access to seawater. If this water can be utilized for aquaculture and agriculture, then scarce freshwater resources can be conserved and the saline water can be used for crop production. Additionally it is possible to use the plant biomass produced as a feedstock for bioenergy production.

We evaluate the lifecycle impacts of aviation biofuel production in the United Arab Emirates  based on a production system that integrates marine aquaculture (shrimp/fish), seawater agriculture (salt-tolerant plants--halophytes) and mangrove silviculture, termed an Integrated Seawater Energy Agriculture System (ISEAS). We compare the hydroprocessed renewable jet fuel (HRJ) produced from the ISEAS against fossil jet fuel using a life cycle assessment (LCA) methodology.  Based on a compilation of the production process and assumptions based on a wide-ranging literature review, we find that an ISEAS can produce aviation biofuels, electricity, and food while afforesting coastal desert land, acting as a long-term sink for carbon, minimizing freshwater consumption, and having beneficial land use impacts when compared to fossil jet fuel production.  Based on a sensitivity analysis, we show that ISEAS HRJ has the potential to emit 55 to 95% less greenhouse gases than fossil jet fuel, and yields an overall positive net energy balance. We show that to achieve more positive results, freshwater use needs to be minimized and biomass yield from the seawater agriculture component needs to be maximized.

Additionally, potential challenges to implementing such systems will be discussed.