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Average wave Power ： 8.2kW

Average hydraulic power ： 4.1kW

Average Electric Power ： 2.6kW

R H E E M L A B .[Sea Surface Measurement by Act ive Microwave Remote Sensing and Development of Ocean Renewable Energy]

Center for Integrated Underwater Observation Technology

htt p : / /s ea s at . i i s . u - tok yo . a c . j p / r h e e m /

Ocean Environmental Engineer ing

Sea Surface Measurement by Act ive Microwave Remote Sens ing and Development of Ocean Renewable Energy Dw-303

G ra d u ate S c h oo l o f F ront i e r S c i e n c e s , D e p a r t me nt o f O c e a n Te c h n o l ogy, Po l i c y, a n d E nv i ron me nt

Remote Sensing of Sea Surface by Microwave Pulse Doppler Radar

Development of Marine Renewable Energy

Sea ice observation using microwave Doppler rader

Hiratsuka experimental tower andmicrowave Doppler radar

A real-time sea surface observation system by using a microwave pulse Doppler radar has been developed. This system is installed on a coastal site or an offshore platform and can observe various ocean phenomena, e.g. tsunami, tide and wave. The features of the radar are as follows.

○Real-time observation ○Remote sensing ○Easy maintenanceThese advantages are effective in countermeasures against coastal disasters. We have also developed sea ice monitoring radar to use in the cold ocean. Using the difference in microwave backscattering from the sea and ice, sea ice position and speed are observed in high resolution.

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3/11 12:00 3/11 15:00 3/11 18:00 3/11 21:00 3/12 0:00

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レーダーに近づいている

レーダーから遠ざかっている

海氷全体の動き

Installation of 5kW tidal energy converter Power generation system 100kW tidal energy converter Roter test in water tank

Renewable Energy is expected as a sustainable energy source which is less carbon dioxide emission. The most important thing is development costs, and the costs depends on the system efficiency. We need to improve the total system efficiency. We are now using hydraulic drive system and developing the high efficiency power generation system which is suitable for adapt to oceanic energy. 5kW tidal energy converter was installed in Shiogama-shi, Miyagi in 2014. The rated output of this power station is only 5kW, but it is very useful as a field test site. We have also developed 100kW tidal energy converter and will plan to expand this system to 250kW in future.

Tsunami on March 11, 2011 microwave backscattering experiment on icebreaker

43kW wave energy converter was installed in Kuji-shi, Iwate in 2016. It was confirmed that the efficiency is almost same as wind power generation (efficiency 32%). In future, we will plan to develop array system of wave energy converters to expand the scale of the power plant.

generator flywheel hydraulic motor

HWL

LWL

43kW wave energy converter

Wave energy

converter

Substation

Cable

Access bridge

Example of wave power generation