1 / 33

Tide Energy Technologies

Tide Energy Technologies. San Jose State University FX Rongère April 2008. Tidal Dams. Tidal Dam. The dam creates a difference of potential energy between the tide pond and the open sea. Δ z. Power Generation. For the chosen control volume, the system is in steady state, then:.

clive
Download Presentation

Tide Energy Technologies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tide EnergyTechnologies San Jose State University FX Rongère April 2008

  2. Tidal Dams

  3. Tidal Dam • The dam creates a difference of potential energy between the tide pond and the open sea Δz

  4. Power Generation For the chosen control volume, the system is in steady state, then: • Incompressible fluid:

  5. Power Generation

  6. Power Generation With: τ: tidal period η: Turbine conversion rate AT: Area of the turbine R : Range of the tide Apool: Area of the tidal pool

  7. Basin Management • To optimize power generation the flow gates are kept closed some time after high and low tides

  8. La Rance Tidal Power Plant • Tide mean range: 8.4m • Tide basin area: 22 km2 10 m 9 m 8 m 7m 6m 5m 4m 3m

  9. La Rance Tidal Power Plant • 24 Units of 10 MW each built between 1961 and 1967 • 700 m dam • 480 GWh/y • CF=23%

  10. The Severn Barrage (UK) • Capacity: 8,640 MW, 17 TWh, CF= 23%, Length=15.9 km

  11. The Severn Barrage (UK) • In the Bristol Channel • Range 8.2 m, Basin Area: 480 km2

  12. The Severn Barrage (UK) • Economics

  13. Tidal Streams • There are generated by the difference of water levels

  14. Golden Gate Currents

  15. Model Ocean Basin z1 z2 R C z1 has the same period as z2 and a phase-shift Current has the same period as z2 and is in quadrature with z1

  16. Current Power • The power of the current is similar to the power of the wind Available energy is proportional to the cube of the current velocity

  17. Shear Effect

  18. The Golden Gate Site • Golden Gate maximum depth = 377 feet

  19. Turbine main components • General concept is similar to wind turbines Gearbox • Increase rotational speed of shaft from turbine • 80-95% efficient Generator and Power Conditioning • Generate electricity • Condition electricity for grid interconnection • Turns at high RPM • 95-98% efficient Rotor • Extracts power from flow • Turns at low RPM 10-30 rpm • Efficiency varies with flow velocity (45% max) Foundation • Secure turbine to seabed • Resist drag on support structure and thrust on rotor Source: Brian Polagye Tidal In-Stream Energy Overview March 6, 2007

  20. Turbines η is the conversion rate of the turbine, typically 25% to 35% • Marine Current Technologies 1 MW, 20m twin rotor prototype currently developed by Marine Current Technologies installed in Northern Ireland’s Strangford Lough (2008) 300 kW, 6 m prototype developed by Marine Current Technologies in operation in the Bristol Channel since 2003

  21. Strangford Lough project • Strangford Lough project

  22. Turbines • Verdant Power 35 kW, 5m Diameter turbine developed by Verdant. Prototype installed in New York at Roosevelt Island (2006 2008). Project of 175 kW

  23. Turbines • Lunar Energy 2 MW, 21m 7 blade rotor prototype currently in development Gravity Foundation: concrete slab Power augmentation by convergent-divergent ducting to increase conversion rate Promising since

  24. Turbines • Clean Current • Pile Mounted • 4 bladed, 14 m, 1 MW • A 65 kW prototype has been Tested at Race Rocks from Sep 2006 to May 2007 Race Rock is a marine reserve run by Lester B.Pearson College on Vancouver Island (Canada)

  25. Turbines • Open Hydro Open Center Rotor Diameter 15 m rated at 1.5 MW Operating Conditions: Current speed > 0.7 m/s Prototype under test at European Marine Energy Center (UK) – Dec. 2006 Source: Bruce H. Adee Tidal Power Technology Update August 9, 2007

  26. Gorlov Different mounting Prototype has been tested at Uldomok Strait in Korea in 2002 1 m diameter and 2.5 m high 1.5 kW

  27. Enemar Kobold Moored – surface mounted 3 vertical articulating blades vertical: 5.0 m diameter: 6 m chord: 0.4 m 25 kW @ 2.0 m/s Prototype has been deployed in Straits of Messina 4 years operational experience

  28. The Energy Business Limited

  29. Foundation Technologies Monopile Gravity Base Hollow steel pile driven or drilled into seabed Heavy foundation of concrete and low cost aggregate placed on seabed Pros: • Deep water installation feasible Pros: • Small footprint • Established technology used in offshore wind Cons: • Large footprint • Scour problems for some types of seabed • Decommissioning problems Cons: • High cost in deep water • Installation expensive for some types of seabed (10-40m) Chain Anchors Tension Leg Submerged platform held in place by anchored cables under high tension Chains anchored to seabed and turbine Pros: • Small footprint • Deep water installation feasible Pros: • Small footprint • Deep water installation feasible • Problematic in practice • Device must have high natural buoyancy Cons: Cons: • Immature technology now being considered for offshore wind in deep water Source: Brian Polagye Tidal In-Stream Energy Overview March 6, 2007

  30. Projects Worldwide

  31. Gulf Stream Current

  32. Florida Current Resource 1.9 2.4 2.8 3.1 Current speed (knots)

  33. Companies to follow • Blue Energy Canada • Clean Current Technology • Marine Current Turbines • GCK (Gorlov) • Lunar Energy • Open Hydro • Enemar Kobold • Verdant Power • Seapower • Tidal Electric • Aquantis Annapolis Tidal Generating Station (USA)

More Related