windsentinel™ technical update no - axys...the vindicator technology was originally developed by...

WindSentinel™ Technical Update No.4 Wind Resource Assessment Buoy

WindSentinel Floating LiDAR Sensor Performance Update – November 2013

CONFIDENTIAL This document and any data disclosed therein is the property of AXYS Technologies Inc. and constitutes and contains proprietary information. Neither receipt nor possession of this document

confers or transfers a right to duplicate or disclose any information contained herein, except as expressly authorized in writing by AXYS Technologies Inc.

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Prepared by

AXYS Technologies Inc.

2045 Mills Road

Sidney, BC

V8L 5X2, Canada

www.axystechnologies.com

Contact

Graham Howe

International Business Development,

Renewable Energy

T: 250 655 5861

C: 250 415-2343

[email protected]



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Table of Contents

EXECUTIVE SUMMARY ................................................................................................................................................................... 4

THE VINDICATOR – A BRIEF HISTORY ............................................................................................................................................. 5

RACE ROCKS – 2009 ....................................................................................................................................................................... 6

DTU HØVSØRE - 2013 .................................................................................................................................................................... 8

FISHERMEN’S ENERGY OF NEW JERSEY – 2013 ............................................................................................................................. 10

NATIONAL CHENG KUNG UNIVERSITY - 2013 ................................................................................................................................ 12

VINDICATOR III SIDE BY SIDE STUDY – 2013.................................................................................................................................. 14

SUMMARY .................................................................................................................................................................................. 16

CREDITS & ACKNOWLEDGMENTS ................................................................................................................................................. 17



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Executive Summary

The WindSentinel™ is the world’s first commercially deployed floating LiDAR device, specifically developed by AXYS to support the

offshore wind resource assessment sector.

The WindSentinel offers the advantages of being considerably less expensive and easier to permit, deploy, and manage than

conventional met masts offshore.

The primary wind resource assessment sensor on the WindSentinel is the Vindicator®, the world’s only commercially available

simultaneous pulse LiDAR with built-in motion compensation, giving the system a significant offshore advantage over conventional

wind resource assessment LiDARs.

As part of the roadmap to market acceptance of the WindSentinel, there have been a number of studies focused on the Vindicator

LiDAR with regard to both its accuracy and the effectiveness of its built-in motion compensation.

These tests have been conducted by AXYS, their clients and third party wind resource assessment consultants and provide clear

evidence of the effectiveness of the WindSentinel system for the purpose of wind resource assessment offshore.

In particular, the tests have shown:

- Consistent R2 levels of 0.99 and higher when comparing the Vindicator with reference stations

- Accurate and precise wind direction measurements that meet industry standards

- Efficient motion compensation performance of the floating LiDAR

This Technical Update will summarize these studies and provide a comprehensive overview of the Vindicator.



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The Vindicator – A Brief History

The Vindicator technology was originally developed by Optical Air Data Systems (OADS) in

the late 1990s. OADS is a high technology, award winning small business located in

Manassas, Virginia, USA. Of special note is OADS’ expertise in the design and engineering of

compact, rugged, all-fiber optic laser wind sensors. OADS has developed this sensor

technology over the past two decades and this has lead to the prototyping and

manufacturing of high accuracy low speed air speed sensor systems for helicopter

applications, commercial laser wind sensors for Utility Scale Wind Turbine control

applications, as well as handheld wind sensors for a wide array of commercial and military

applications. The Company currently holds over 27 patents in the fields of laser Doppler

velocimetry and its applications.

The system that evolved into the Vindicator was originally used by helicopters to assist with

landings in degraded visibility environments, which led to the development of the sensor

durability and motion compensation capabilities demonstrated by the system today.

In 2009 AXYS, seeking a suitable sensor for offshore wind resource assessment, entered

into an exclusive arrangement to market the Vindicator for this purpose and commenced

deployment of the first generation Vindicator. The core technology contained in this system

is the same used today.

In 2013, the Vindicator III was developed, leveraging OADS’ ongoing work with other

applications of the sensor to introduce a new form factor, including the air blade lens

cleaning technology.

As can be seen below, OADS has continued to support ongoing refinement of the Vindicator and remain committed to developing

new applications to support the continuing evolution of the offshore wind resource assessment sector.

Figure 1 - Vindicator I

Figure 2 - Vindicator III



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Race Rocks – 2009

The Race Rocks trial, which ran for a month in October/November of 2009, was the world’s first validation of a floating LiDAR

system. Intended as a proof of concept for the WindSentinel, the trial deployed a floating Vindicator compared to the same sensor

on a fixed platform onshore. The trial was a successful validation of the system and, most important, confirmed the effectiveness of

the motion compensation feature of the Vindicator.

Location Race Rocks, approximately 20 miles south west of Victoria, BC in the Juan de Fuca Strait.

System tested Vindicator I

Reference system Vindicator I

Distance between sensors 700 metres

Summary of results “the buoy mean wind speed agreed within 2% of the reference LiDAR measurements” - GL-

Garrad Hassan paper - EWEA March 2011

Figure 3 - WindSentinel buoy deployed at Race Rocks



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Sample Data

Table 1 - Race Rocks Wind Speed Correlation Data



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DTU Høvsøre - 2013

A three month validation study at DTU’s Høvsøre testing facility commenced in mid-March 2013 and ended in early May. Interim

results from the study have been produced and a second phase of the study will be completed in early 2014.

Location Høvsøre, Denmark

System tested Vindicator III

Reference system Høvsøre met mast

Distance between sensors 11m

Summary of results The Vindicator demonstrated a high level of data availability, good quality wind direction data

and wind speed R2 of 0.99 and higher

Figure 4 - Vindicator III installed in WindSentinel Land Station at Høvsøre



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Sample Data

» 60m

Test Value

Availability [%] 90

Gain [-] 1.007

Offset [m/s] 0.150

R2 [-] 0.992

Absolute mean deviation [m/s] 0.212

Standard deviation of deviation [m/s] 0.228

» 80m

Test Value

Availability [%] 93

Gain [-] 0.990

Offset [m/s] 0.149

R2 [-] 0.992



» 100m

Test Value

Availability [%] 92

Gain [-] 1.003

Offset [m/s] 0.056

R2 [-] 0.990





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Fishermen’s Energy of New Jersey – 2013

The Fishermen’s Energy WindSentinel was launched in early 2012, the second commercial deployment of the system. From mid-

March to mid-May 2013, Fishermen’s ran a system validation campaign against a shore-based WindCube under the direction of GL-

Garrad Hassan.

Location Off the coast of Atlantic City, New Jersey

System tested Vindicator I

Reference system WindCube v2


Summary of results The WindSentinel wind speeds showed a good degree of correlation given the distance between

the two sensors and the complexity of the terrain for the study.

In their report on the study GL-Garrad Hassan stated:

- “No significant sensitivity to pitch and roll motions was observed….this result is indicative of

an efficient motion compensation performance of the floating LiDAR.”

- “The WindSentinel provided accurate and precise wind direction measurements which are

deemed to be compliant with industry standards.”

Figure 5 - WindSentinel deployed off Atlantic City



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Sample Data

Table 2 - Fishermen's Energy Wind Speed Correlation Data



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National Cheng Kung University - 2013

National Cheng Kung University took delivery of their WindSentinel in late May with the intention of using the system as part of the

Taiwanese government’s long-term plan for offshore wind power. In October 2013 the University ran a comparison study between

their WindSentinel Vindicator III docked offshore with an onshore WindCube owned by the Taiwan Ocean Research Institute.

Location Tainan, Taiwan


Reference system WindCube V2


Summary of results Given the distance and the complex terrain (the test location has a number of high buildings) the

systems showed good correlation with an R2 of around 0.98

Figure 6 - WindSentinel deployed in Tainan Figure 7 - Location of WindSentinel buoy and WindCube



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Sample Data

Table 3 - NCKU Wind Speed Correlation Data



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Vindicator III Side by Side Study – 2013

In 2013 the US Navy purchased two Vindicators and a WindSentinel as part of a project intended to establish the degree of

uncertainty between a fixed and floating LiDAR system. As an initial step in this study, the two Vindicators have been run side by side

on the roof of AXYS’ facility to establish a baseline uncertainty measurement.

Location AXYS facility, Sidney BC, Canada.


Reference system Vindicator III

Distance between sensors Side by side

Summary of results Both wind speed and direction show good correlation with high levels of data availability. The

wind speed R2

showed 0.99

Figure 8 - Vindicators on AXYS rooftop testing facility



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Sample Data

Table 4 - Side by Side Wind Speed Correlation Data



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Summary

The WindSentinel has now completed a range of studies designed to establish the effectiveness of the system for offshore wind

resource assessment. These studies, (more than for any comparable system available in the market), have demonstrated:

- Consistent R2 levels of 0.99 and higher when comparing the Vindicator with reference stations

- Accurate and precise wind direction measurements that meet industry standards

- Efficient motion compensation performance of the floating LiDAR

Future studies planned for the system include:

- A Vindicator III unit will be sent to DTU Høvsøre in early 2014 to complete phase two of the study at that location.

- The US Navy will deploy their WindSentinel early in 2014 and run a comparison between this system and a WindSentinel

LandStation deployed on an oil rig to establish the degree of uncertainty between the two systems. This study is being

undertaken under the guidance of DNV GL.

- NCKU plan to deploy their WindSentinel next to an offshore mast for further validation in 2014.

Additional studies are also currently underway and their results will be published as soon as they are available.



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Credits & Acknowledgments

AXYS would like to thank our clients for their ongoing support of the WindSentinel system.

In particular we would like to thank the following for their support of this paper:

- Fishermen’s Energy of New Jersey

- National Cheng Kung University

We would also like to thank the following 3rd

party wind resource assessment consultants for their input and feedback:

- DNV GL (including the employees of GL- Garrad Hassan)

- Oldbaum Services

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