Mission Statement: Develop a wave energy extraction device which generates electrical power on a self-sustaining buoy. Salient Features: Use of COTS – Low Initial Cost – Reliable (proven technologies) Use of Cable Reel – Adoptable to large range of wave conditions Use of Flywheel – Harvest kinetic energy Minimum Exposure – High maintainability – Low maintenance cost Renewable Energies –Environmentally conscience –Future energy concerns Major renewable energies: Wind, Solar, and Wave Why Offshore Wave Energy In Comparison to Other Renewable Energy Sources Wave Energy Densities (MW) “About 0.1% of world ocean waves can power the entire world 5 times over.” Advantages of Offshore Wave Energy Offshore Wave Power Solar Power Wind Power Energy Density HighLow Availability90%20%-30% Potential Sites Virtually Unlimited LimitedVery Limited BUT… Very Capital Intensive Must Survive Extreme Weathers Cost/Power Efficiency Limitations Identify Opportunities Customer NeedsTarget Values State of the Art Review Product Architecture / Technical Analysis Concept Generation Concept Screening and Scoring Design SelectionFinal Design Basic Operation 1.The buoy is forced into motion by surges in water level. 2.The pull on the reel cable rotates the shaft and energy is stored in the Flywheel as kinetic energy. 3.The generator converts the kinetic energy to electrical energy. Cable Reel Wave Swell WEPG Buoyancy Force Sea Floor The Basic Concept How It Works ADVISORS: Dr. Kishore Pochiraju Mike Raftery SENIOR DESIGN TEAM: Biruk Assefa Lazaro Cosma Josh Ottinger Yukinori Sato Applications: 1.Self-sustained offshore buoys (data buoys, Tsunami detection system, etc.) 2.Industrial scale power generation Key Business Goals: 1.Develop a novel design to meet requirements 2.Proof of concept for the design Project Introduction: Design Location: Raritan Bay, New York Harbor Data collected from the past 5 years and statistically analyzed for significant wave height and period Wave HeightWave Period Mean Height: 12.2 inches 95% C.L.: 3.94~27.95 inches Mean Period: 7.14 sec 95% C.L.: 3.1~12.8 sec Wave Condition Analysis The Design Wave Conditions Special Thanks to: Mechanical Engineering Department Institute Machine Shop: George Wohlrab, Bruce, and Crew Davidson Laboratory Webb Institute Wave Energy Power Generator Prototype The Design Process How we did it Prototype Test: Prototype Design: Spring Operated Reel Function: Convert linear buoy motion into rotational shaft motion Design Aim: Maximize angular velocity of input shaft –Velocity dependant on reel diameter –Spring should handle large waves & not suppress small waves One-way Clutch Function: Convert oscillatory motion of reel into unidirectional motion Design Aim: Utilize a one-way clutch bearing that can handle maximum input torque with a desired FOS Gearbox Function: Increase shaft speed for flywheel / alternator system Design Aim: Increase speed by reducing torque to optimize operating RPM for alternator Flywheel Function: Maintain RPM at alternator Design Aim: Maximize momentum on flywheel, while minimizing required weight –Acts as a mechanical battery by storing kinetic energy Alternator Function: Convert mechanical shaft horsepower to usable electrical power Design Aim: Maximize power output at minimum RPM One-way Clutch Function: Disconnects gearbox from flywheel Design Aim: Disengages when gearbox output shaft decelerates quicker than flywheel subsystem Test Matrix Results Results show the effects of various flywheel sizes Controlling EMF results in optimal power extraction Increasing gear ratio will increase shaft power For given wave conditions Max Power = 60 Watts Recommendations Development of optimum low RPM generator Maximize heave displacement and minimize roll effects Test alternative gear ratios Optimize Flywheel vs. Rotor EMF for varying wave conditions * The plots above are outputs of a verified model based on Torque vs. RPM and Deceleration vs. RPM characteristics from actual device performance measurements from the test matrix. Awards ASME Regional Student Conference District A Fairleigh Dickinson University: April 1 st 2006 Second Place in Oral Presentation Competition