byK. Takagi, The University of Tokyo

Fukushima Floating Wind Turbine (METI): $280M

Offshore Wind Turbine Technology Development and Demonstration (Cabinet, METI, MLIT,MOE): $141M

Marine Energy Technology Development and Demonstration (METI, MEXT) : $25M

NEDO Project

Addressing energy and global environmental problems

Enhancement of Japan's industrial competitiveness

What is NEDO (New Energy and Industrial Technology Development Organization)?

http://www.nedo.go.jp/english/introducing_index.html

Type DeveloperWave Mitsui Engineering &

ShipbuildingWave MHI Bridge & Steel Structures

EngineeringTOA

Wave GyrodynamicsHitachi Zosen

Wave Ichikawa DobokuKyoritsu ElectricIdea Consultants

Tidal Kawasaki Heavy IndustriesWind &Tidal

MODEC

Type DeveloperOcean Current

The University of TokyoIHIToshibaMitsui GSSI

OTEC KOBELCOSaga University

Tidal Sasebo Heavy IndustriesThe University of TokyoKyusyu University

Tidal Nakashima PropellerPenta-Ocean ConstructionHiroshima Institute of Technology

Demonstration Projects Technology Development

2008-2010Surface floating UT: Yamaguchi, Suzuki, WasedaNMRI Supported by MLIT

2009-2010Floating contra-rotatingUT: TakagiSupported by NEDO

Vertical Load Anchor

Mooring Line Current

2010-2012 Floating contra-rotating UT: Takagi, KinoshitaSupported by JSPS(MEXT)

2013 TECO Green Tech ContestInternational ChampionNew Design Concept of Ocean Current Power Generation System

2011-2015Floating Twin-TurbineUT: Takagi, WasedaIHI, Toshiba, Mitsui GSSISupported by NEDO

Ocean current is one of big energy resources.

Total demand of electricity in Japan is 100GW.

Current is converged at several areas. Current axis is stable.

It is reasonable to assume that the rated speed is 1.5m/s at these areas

Diameter is big. Turbine gets big thrust force and torque

moment. Torque moment must be canceled out Water depth is deep. Floating type could minimize its weight Floating type is easy to install.

Floating type has an advantageTwin-turbine for torque moment

Rated speed Rated power Turbine diameter1.5m/s 2MW about 40m

The direct drive power train, where the turbine and the generator are connected directly, is proposed

Electromagnetic velocity meters

Buoy system for ADCP measurement

6DOF Main Body + Two Turbines + Two mooring lines (Fully coupled)

Wave radiation and diffraction +cross flow drag for the main body

Wing element theory for the lift and drag forces

Lumped mass method for mooring line

Z Towing Carriage

Mooring Line

Strut

5.1m

3.0m 5.0m

30°

CameraX

Model

Spring

0

20

40

60

80

100

120

140

160

180

0 500 1000

kN

Arclength (m)

Max Effective Tension

Free CatenarySingle Point MooringFloater InstalledMulti Points Fixed

‐0.005

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0 200 400 600 800 1000

rad/m

Arclength (m)

Max Curvature

Free Catenary

Single Point Fixed

Floater Installed

Multi Points Fixed

Ocean current is one of big renewable energy resources not only for Japan but also for Taiwan.

We can realize this new idea in near future, although there are many elemental technologies which we need to develop.

This work is supported byNew Energy and Industrial Technology Development

Organization (NEDO) I am grateful for their support.

Thank you for your attention.