1. Solar Powered Oyster Upweller System Auburn University Biosystems Engineering Department Design Team: Sam Deck, Carson Edge, Manny Norrell, Keith Roberts Client: Dr. Bill Walton, Associate Professor & Extension Specialist Design an off grid, mobile oyster upweller system with detachable silos that can be assembled/disassembled by one person in one hour with a material cost below $32,000. Design a PV system to supply adequate power to the system for a 24 hour runtime during various growth cycles from May through October. Develop an ocean water pumping and distribution system capable of supplying 0.08 gpm/ in 2 that can withstand a Gulf of Mexico maximum salinity level of 35 ppt. Design Objectives Background Gulf Coast Locations The production of farm raised oysters is a growing industry in the United States with many locations around the Gulf of Mexico having the potential to support oyster farming operations. Many oyster farmers around the Gulf of Mexico rely on oyster upweller systems to provide oyster spat needed to begin their farms. Current upweller designs rely on grid power and are immobile, making them susceptible to severe weather. These upwellers operate 24 hours a day for various growth cycles from May through October. The systems are designed to circulate a continuous flow of ocean water through suspended silos filled with oyster seed and provide a controlled environment. The forced upwelling expedites shellfish growth by increasing delivery of phytoplankton. Off Grid Oysters has designed a mobile and grid independent Gulf Coast oyster upweller system capable of producing comparable output to existing upweller systems. Acknowledgements The Off Grid Oysters design team would like to thank Dr. Mark Dougherty, Dr. Oladiran Fasina, and Dr. Bill Walton for their guidance and support throughout this engineering design process. Figure 1: Capable of operating on any Gulf of Mexico coastline Existing Gulf Coast systems are limited to areas with grid power availability and require constant flow of ocean water through the silos to grow oysters. Current off-grid systems are floating, immobile and only used on the northeast coast of North America where there is a low risk of hurricanes. Off Grid Oysters meets the specified design objectives for a mobile, solar powered oyster upweller system. The system is designed on a trailer to enable oyster farmers to relocate the system during extreme weather events and operate in remote locations. The ocean water flow through the system is supplied by a one horsepower submersible pump powered by five Grape Solar® panels capable of supplying a total of 1,950 watts. The pump will supply ocean water at 23.75 gallons per minute (gpm) to four 20 gallon silos each resulting in a total system flow of 95 gpm. The system will also include a battery bank of 8, 12 volt deep-cycle marine batteries capable of supplying the system for two consecutive days without sunlight. This system will have the capacity to produce approximately 1,134,870 20 mm oysters during the growing season. Design Summary Financial Analysis Figure 4: Exploded view of silo Figure 5: Ocean water flow diagram through silo Figure 3: Mobile Upweller System Figure 6: Electrical diagram of solar components Capital Cost PV System$3,170 Electrical Components$12,501 Trailer Components$2,675 Upweller Components$5,098 Subtotal$23,444 Contingencies (10%)$2,344 Tax (11%)$2,579 Grand Total$28,367 Flow Through Mesh Screen in 20 Gallon Silo Ocean Water Outlet Ocean Water Inlet Upweller Silos Electrical Components Enclosed Battery Bank Ocean Water Discharge Fresh Water Sprayer Ocean Water Inlet 390 Watt Solar Panel Array [Submersible Pump in Ocean] Charge Cont. Inverter Battery Bank Combiner Charge Cont. Inverter Battery Bank Charge Controller Areas available for oyster production Combiner Solar Panel Array Pump Inverter Battery Bank 2” Uniseal Outlet Fitting Trailer Bed 2” Schedule 40 PVC Outlet Pipe 2” Schedule 40 PVC Inlet Pipe 2” Uniseal Inlet Fitting 44 Gallon Silo 20 Gallon Silo Profit 4 Silos Predicted Output of 20-25 mm567,435 Cost of 2 mm Oyster Seed$3/1,000 oysters Total Price of Oyster Seed$1,702.31 60% Survival Rate340,461 20/25 mm Juvenile Oysters Cost per 1000$50.00 One Run Profit from Oyster Spat for 4 Silos$15,320.75 Profit from Two Runs per Season$30,641.49 Two Run Yearly Profit: Year 1$2,354 Year 2$30,641 Year 3$30,641 Ocean Water Inflow