SONAR FOR ENVIRONMENTAL MONITORING OFMARINE RENEWABLE ENERGY TECHNOLOGIES

Project Coordinator :

Div. Electricity – Uppsala University

WavEC

CARL TRYGGER'S & J GUST RICHERT'S FOUNDATIONS

FRANCISCO FRANCISCOJAN SUNDBERG

Renewable energy - Key trends

2Source: International Energy Agency 2016

3

Marine renewable energy technologies Framework

•Resource assessment

•Numeric modelling

•Energy converters

•Control systems

•Grid connection

•Deployments

•Environmental monitoring

•Manufacturing

•Commercialization

•Marketing

Marine renewables Framework

Objective & vision

4

5

Minimize impact & risksassociated with subseawork

Vision

Objective

Develop a platform ableto monitor operation, installation & maintenance of marine renewables

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Why the use sonar?

MULTI CHANNEL

RECEIVER

(ELECTRONICS)

COMPUTER &

CONTROLSDISPLAY

TRANSDUCER

Source Level (SL)

Target Strength (TS)

Transmission Loss (TL)

TARGETNoise Level (NL)

Directive Index (DI)

Array Gain (AG)Digital Signal

Detection Threshold (DT)

Beamwidth

Beam swath

Sonar mechanism

Superior underwater Remote Sensing performance especially in murky waters

Why Sonar?

The actual monitoring platform

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• Design

• Construction

• Test

• Deployment

• Validation

The actual monitoring platform

submerged unit

communication buoy

portable pole mount

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Design

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The actual monitoring platform

Cameras

Multibeam sonar

Split-beam sonar

Dual-beam sonar

Battery box & control electronics

Installed devices

How do we deploy?

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Deployment strategies

Ds

Vessel

GPSantenna

WL

MBS

DBS/SBS

Pole mount

MBS

DBS

Configuration-A

Ds

fixed structure

Pole mount

WL

Configuration-B

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The actual monitoring platform

Ds

MBSSBS

Vessel

GPSantenna

Tripod

WL

Configuration-C

Ds

fixed structure

WL

Configuration-D

Communication buoy

Submerged Unity

WL

Configuration-E

How data is processed?

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The data acquisition and analysis toolDAQ

DATA PROCESSING - MATLABROUTINES

FILTERS: NOISEREDUCTION, TARGET DETECTION& CLASSIFICATION

FILTEREDECHOGRAM

OUTPUT DATA

(ACOUSTIC

BACKSCATTER

INTENSITY)

DECODER

(SONAR

VIEWER)

DECODER

(MATLAB)

RAW DATA (AMPLITUDE

ECHOGAM)DBS

GEO DATA

14Number of Pings

Dep

th [m

]

1000 1500 2000 2500

0

0.5

1

1.5

2

2.5

[dB]

99

100

101

102

103

The actual monitoring platform

• Biomass estimation

• WEC - TEC detection

• Structure and bottom inspection

• Hi-resolution bottom-depth measurement

• Cavitating flow measurement

Performance results

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Performance results

WEC detection

A diver

UU WECWEC’s acoustic shadow

Ds

Vessel

GPSantenna

WL

MBS

DBS/SBS

Pole mount

MBS

DBS

Configuration-A

UU WEC baseplate

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Multibeam acoustic image

Performance results

TEC detection

A UU turbine Turbine’s acoustic shadow

b

Ds

fixed structure

Pole mount

WL

Configuration-B

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Multibeam acoustic image

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Hi-resolution bottom-depth measurement

To reduce risk of….

Conclusions

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Conclusions

So far the platform is able to perform:

• Target detection (in 3D as ecogram & 2D as acoustic image)

• Bottom inspection

• Hi-res bathymetry

• Biomass estimation

• Observation of cavitating flow

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Future work

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Future work

• Improve the system-integration

• Improve the deployment procedure

• Finalize the DAQ

• Do additional short and long-term surveys

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Secondments

Seabased Industry AB

• Sea bottom inspections

• Tide data analysis for a WEC’s tide-compensator

• Wave climate analysis

• WEC Deployment support at Sotenäs Wave Power Farm

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I. Parwal, A., Remouit, F., Hong, Y., Francisco, F., Leijon, M., et al., (2015). Wave Energy Research at Uppsala Universityand The Lysekil Research Site, Sweden: A Status Update. Proceedings of the 11th European Wave and Tidal Energy Conference(EWTEC), Nantes, France, 6-11th Sept 2015.

II. Francisco, F. Sundberg, J. (2015). Sonar for Environmental Monitoring. Initial Setup of an Active Acoustic Platform. TheTwenty-fifth (2015) International Ocean and Polar Engineering Conference Kona, Big Island, Hawaii, USA, June 21-26, 2015.Kona, Big Island, Hawaii, USA, June 21-26, 2015.

III. Francisco, F. Sundberg, J. (2015). Sonar for Environmental Monitoring: Un-derstanding the Functionality of ActiveAcoustics as a Method for Monitoring Marine Renewable Energy Devices. Proceedings of the 11th European Wave and TidalEnergy Conference (EWTEC), Nantes, France, 6-11th Sept 2015.

IV. Francisco, F. Sundberg, J. Sonar for environmental monitoring: Construction of a multifunctional active acoustic platformapplied for marine renewables. (Sub-mitted paper)

V. Francisco, F. Carpman, N., Dolguntseva, I., Sundberg, J. Observation of cavi-tation-induced flow using multibeam anddual-beam sonar systems. A compari-son of wake strength caused by propeller vs waterjet thrusted ferry boats: in a marinerenewable energy perspective, Part-a. (Manuscript)

VI. Francisco, F. Sundberg, J., Ekergård, B., Leijon, M. An estimation of wave energy flux and variability in the Ada Foaregion: Towards commissioning of the first commercial wave power farm in Africa – Ghana. (Submitted paper)

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List of Papers

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