Tidal Power Methods of Extraction Patrick Dunlap

Definition and Motivation What is Tidal Energy? What is Tidal Energy? Energy contained in a tide, especially that which can be converted to electricity. Energy contained in a tide, especially that which can be converted to electricity. Why Tidal Energy? Why Tidal Energy? Declining availability of fossil fuels and global climate change. Declining availability of fossil fuels and global climate change.

Tidal Theory Energy Source Tidal Cycle Amplitude

Traditional Method Harnesses Potential Energy within tide Harnesses Potential Energy within tide

Current Plants CountrySite Installed Power (MW) Basin Area (km 2) Mean Tide (m) France La Rance Russia Kislaya Guba CanadaAnnapolis ChinaJiangxia

Disadvantages Environmental Environmental Economical Economical Design Design

New Method Involves extraction of kinetic energy from a tide, given in KE Flux Mechanical processes for extraction are based on the hydrofoil.

Actual Power Output Energy Flux equation is multiplied by a Constant C p Energy Flux equation is multiplied by a Constant C p The differential dA is now representative of the sweep are of the blades The differential dA is now representative of the sweep are of the blades

Site Selection High average velocity (currently looking at > 3 m/s) High average velocity (currently looking at > 3 m/s) High local energy demand High local energy demand Within Current Technical Limits Within Current Technical Limits

Comparison to Wind Advantages Density Predictability Aesthetics Disadvantages Scale Construction

Current Projects In August SeaGen, a 1.2 MW, dual turbine unit will be connected to the power grid 2.25 MW turbine will supply Portugal Last December two turbines installed in NY’s East River

References Tidal Energy, AM Gorlov, 2001 Tidal Energy, AM Gorlov, 2001 Choosing and Evaluating sites for Tidal Energy Evaluation, Byrden, Proceeding of the Institute of Mechanical Engineers, V 218 Choosing and Evaluating sites for Tidal Energy Evaluation, Byrden, Proceeding of the Institute of Mechanical Engineers, V 218 Tapping the Power of the Seas, Economist, V383 Tapping the Power of the Seas, Economist, V383 Tidal Current Energy Extraction: Hydrodynamic Resource Evaluation, Couch, Proceeding of the Institute of Mechanical Engineers, V 220 Tidal Current Energy Extraction: Hydrodynamic Resource Evaluation, Couch, Proceeding of the Institute of Mechanical Engineers, V