Renewable Energy Aquaculture Aeration For Small and Mid-Sized Farms

Low dissolved oxygen (DO) levels are the most frequent cause of catastrophic fish mortalities in aquaculture farming, resulting in substantial dollar losses of valuable aquaculture crops annually. To address this problem, the U.S. aquaculture industry most often uses floating paddlewheels and/or aspirating aerators for nightly or continuous aeration and circulation of aquafarm waters. However, power consumption with the use of these powerful devices results in high electrical operating costs. Low-energy submerged diffuser aeration and destratification systems have been shown to be a very efficient and economical means of pond and lakebed destratification and aeration. The greatly reduced power requirement of such systems provides an opportunity to combine an appropriately sized diffuser aeration system with a suitable renewable energy power source, and significantly reduce or eliminate the high recurrent electrical cost of operating traditional aquaculture pond aeration systems. To determine the technical feasibility of this technology for commercial aquaculture applications, the research team will research the following objectives: 1) Determine the performance characteristics and air output of two direct-drive compressor aeration windmills and four or more small wind electrical turbines at HFC's aquafarm location, and compare these results unit-to-unit to facilitate subsequent pairing with appropriate power sources; 2) Determine the electrical output of two or more different brands of solar panels of differing size and output at HFC's aquafarm location and compare to STC and PTC ratings, and unit-to-unit; 3) Determine the operating load power draw and air output of three DC compressors, two AC compressors, and one AC regenerative blower at HFC's aquafarm site and compare unit-to-unit and against the air output of the two direct-drive compressor aeration windmills; 4) Design and assemble two preliminary mock-up renewable energy aeration systems (one wind-powered and one solar-powered), and bench test the performance and air output of each; and 5) Field test the aeration performance of the two mock-up units against the two direct-drive windmill aerators in HFC's existing 3 ton, 1 m deep aquaculture tanks, and at varying depths in HFC's existing 35 m deep pond. The results of the Phase I feasibility research will lay the groundwork for the planned Phase II research and development work to design and test two prototype renewable energy aquaculture aeration devices. Phase III commercialization is anticipated.