Issued: 18 March 2019 Crystal Brook Energy Park Study, SA · Generators (WTG) at Crystal Brook Energy Park (Energy Park). The BA Managed Services operating near the proposed WTGs

Version: 0.7 – Issued: 18 March 2019

Document No.: WPV-REP-1597

Crystal Brook Energy

Park Study, SA

bai communications | Document No.: WPV-REP-1597 page i

CONTENTS

1 About this document ............................................................................................. 1

2 Introduction ............................................................................................................... 1

3 Interference Assessment and Results .............................................................. 2

3.1 AM Re-radiation Interference Methodology .....................................................2

3.1.1 Coverage Impact ............................................................................................2

3.1.2 EME Impact ......................................................................................................2

3.2 DTV Scatter Interference Methodology ..............................................................3

3.3 AM Re-radiation Interference Results ................................................................. 4

3.3.1 Coverage Impact ........................................................................................... 4

3.3.2 EME Impact ......................................................................................................6

3.4 DTV Scatter Interference Results ...........................................................................7

4 Detailed Analysis and Remediation Options ................................................ 8

4.1 AM Re-radiation Analysis .........................................................................................8

4.2 AM Remediation Options ........................................................................................8

4.2.1 De-tune WTGs.................................................................................................8

4.2.2 Power Increase ................................................................................................8

4.3 DTV Scatter Analysis ................................................................................................ 10

4.4 DTV Remediation Options..................................................................................... 10

4.4.1 DTV Infill Facility ............................................................................................ 10

4.4.2 VAST Receivers.............................................................................................. 10

5 Field Survey.............................................................................................................. 10

6 Electromagnetic Noise ........................................................................................ 11

7 Licenced Services ................................................................................................... 11

8 Conclusion................................................................................................................ 11

bai communications | Document No.: WPV-REP-1597 page 1 of 12

1 About this document

Author: For any queries relating to this document contact Grant Shapcott, T +61 (0) 2 8113 4871, M +61 (0) 427 914

726, [email protected]

Approver

Name Role Department Approval Date

Grant Shapcott Engineering Manager Antennas and Structures 18/03/2019

History

Issue Date Author Reason

0.1 25/10/2018 Jonathan

Armstrong

Draft DTV Component

0.2 03/11/2018 Lucas Masters Draft AM Component

0.3 06/11/2018 Aasif Javed Draft for Internal Review

0.4 30/11/2018 Grant Shapcott Release for Client Review

0.5 11/02/2019 Aasif Javed / Grant

Shapcott

Incorporate Client’s

Comments and Remediation

Options

0.6 27/02/2019 Grant Shapcott Incorporate Operational

Considerations

0.7 18/03/2019 Grant Shapcott Clarify Operational

Considerations

2 Introduction

Neoen have advised Broadcast Australia (BA) with preliminary proposals for the installation of 26 Wind Turbine

Generators (WTG) at Crystal Brook Energy Park (Energy Park). The BA Managed Services operating near the

proposed WTGs is Crystal Brook MF (5007) for AM Radio Services and The Bluff (5027) for Digital Television (DTV)

and FM Radio Services.

BA have conducted field tests on an existing Wind Farm near Lake Bonney, SA. The field test measurements

concluded that FM radio had some minor reflections observed but would not be expected to cause any noticeable

effect on reception. Thus, this report will therefore not consider further the impacts on FM broadcast.

BA has thus far only considered the installation of WTGs. No further analysis has been conducted on the impact of

additional interference that could be generated from the additional infrastructure apart from the WTGs. Impacts to

point to point and point to multi-point in the vicinity of the Energy Park have not been considered by BA.


There is currently a single AM Service broadcast from Crystal Brook MF. Desktop modelling using EZ-NEC

simulation tool was used to model the WTGs and analyse the impact on the AM broadcast.

A single EME calculation at the closest WTG (CB19) due to the proximity of the AM Service has been calculated as

part of this report. Further EME analysis, including at every WTG location, should be considered for the installation

and operation/access of the WTGs due to the proximity to the Crystal Brook MF site.

There are currently 4 FM and 5 DTV services broadcast from The Bluff. Desktop modelling using ICS Telecom

simulation tool was used to model the WTGs and analyse the impact on the DTV broadcast.

The DTV simulation tool models the impact on the DTV broadcast from scattering interference within 10 km of the

broadcast transmitter. There may be an impact on the fringes of coverage, but as the Wind Farm will consist of 26

WTGs, the probability of impacting the overall coverage at the fringes will be minimal.

The AM simulation tool models the impact on the AM broadcast from re-radiation interference of the broadcast

transmitter antenna pattern.

This report only considers the scenario sent to BA. Any changes to the WTG parameters, numbers or locations will

need to be reassessed for interference.

3 Interference Assessment and Results

BA has modelled the WTGs at Crystal Brook using EZ-NEC modelling tool for the AM service and ICS Telecom for

the DTV Services. The WTG coordinates and heights used were provided by Tom Jenkins from Neoen via email

correspondence on 23rd October 2018.

The WTGs were modelled on a 4.8 MW turbine model with 161 m hub height and 79 m blade length.

3.1 AM Re-radiation Interference Methodology

Two aspects of the AM Interference were analysed. The coverage impact to the AM service, from the WTGs and the

EME Impact on the WTGs, from the AM service.

3.1.1 Coverage Impact

The effect of the 26 WTGs on the existing 10 kW 639 kHz AM radio service out of Crystal Brook MF was modelled in

a number of ways and the worst case scenario predicted was when all blades were in a “Y” formation. Once this

scenario was applied to all the WTGs, the effect on the existing antenna pattern was analysed. The WTGs are

depicted in EZ-NEC modelling tool in Figure 1.

The angle of the blades in the X-Y plane was also varied to simulate the effect on the antenna pattern for different

wind directions.

3.1.2 EME Impact

The EME analysis was carried out by placing the test locations at a distance of 0.3m in front of the WTG support

pole and then varying the Z component in steps of 1 m to determine the height of the EME maxima. This was done

for both electric and magnetic fields. This is based on the Australian Radiation Protection and Nuclear Safety

Agency (ARPANSA) General Public Reference Levels.


Figure 1: Diagram of the 26 WTG’s depicted in the EZNEC software.

3.2 DTV Scatter Interference Methodology

A conservative Radar Cross Section value of 3,000 m2 per turbine was used (as per ICS telecom software

recommendations). Using the inbuilt ICS telecom model, each turbine was modelled as a simple plane reflector and

a C/N map was produced using the scatter contribution from each WTG to each receive location. This method of

calculating C/N incorporated antenna discrimination as per ITU-R 419 by assuming receive antennas are orientated

towards the transmit site.

Locations within 10 km of the Wind Farm were assessed, as scatter interference outside of this 10 km radius is not

likely to occur (ITU-R BT 1893).

Based on the ACMA planning guidelines, the required C/N for adequate reception is 20 dB (which is based on the

64QAM 2/3 modulation mode). The ITU-R BT.1893 highlights that “for Reception areas where the dynamic

multipath levels are less than 25 dB below the direct signal may experience increments in the C/N threshold ratios

for QEF condition by up to 8 dB”. The C/N threshold is therefore increased to 28dB for adequate reception.


3.3 AM Re-radiation Interference Results

3.3.1 Coverage Impact

The software predictions indicate a minor ripple effect on the existing antenna pattern due to the installations of

the WTGs. The maximum ripple distortion occurs on a bearing of 332°T and is a reduction of 0.7dB. The wind

direction (plane of the blades in x-y directions) has negligible effect on the antenna pattern. The main contributing

factor to this distortion is the comparable relative lengths of the vertical elements with the wavelength of the AM

service (469m at 639 kHz).

Figure 2: Comparison of antenna pattern before (green) and after installation of WTGs (blue)

The maps below show the predicted coverage before (Figure 3) and after (Figure 4) the installation of the WTGs on

the AM Service.


Figure 3: AM Service Predicted Coverage before the installation of WTGs

Figure 4: AM Service Predicted Coverage after the installation of WTGs


3.3.2 EME Impact

EME analysis was carried out at the nearest WTG (CB19). A maximum E field of 2.7 V/m (0.1% of RPS3 Australian

Standard – General Public Reference Level) was calculated at a height of 62 m. A maximum H field of 0.05 A/m

(0.2% of RPS3 Australian Standard – General Public Reference Level) was calculated at a height of 0 m.

It is recommended that Neoen undertake RF EME assessments on the WTGs, both during operation and

construction phases, especially with mobile cranes being deployed.


3.4 DTV Scatter Interference Results

Based on results of the simulation, any expected DTV scatter interference is restricted to within 2 km of the

proposed WTG locations.

A map of the WTG locations and the affected DTV interference are is shown below in Figure 5.

Figure 5: Orange areas highlight areas where C/N is between 20-28 dB, red areas highlight areas where C/N is less than 20 dB


4 Detailed Analysis and Remediation Options

Detailed population and coverage analysis were undertaken for AM and DTV impact scenarios and possible

remediation options tabled.

4.1 AM Re-radiation Analysis

Detailed coverage analysis was undertaken on the impact due to the installation of the WTGs. A population

reduction to AM Service of approximately 3,900 persons is predicted, based on 2016 Census data. The detailed

population numbers are in Table 1 below.

Crystal Brook AM Base Power to

Mast 10 kW

Base Power to Mast

10 kW

Frequency (kHz)/Service Coverage Grade Existing Post WTG Difference

639 kHz – 5CK

Urban (10mV/m) 79,847 79,661 -186

Suburban (2.5mV/m) 1,171,552 1,206,434 34,882

Rural (0.5mV/m) 339,403 300,781 -38,622

Total Population

Covered 1,590,802 1,586,876 -3,926

Table 1: Crystal Brook AM Post WTG Population Figures

4.2 AM Remediation Options

There are currently two main options considered to remediate the predicted population impacted. Whilst not

exhaustive, the options presented are those that can be implemented and demonstrably have an impact on

mitigating the loss in population.

4.2.1 De-tune WTGs

This would involve constructing a series of wires to be run on the outside of the wind turbine and tuned to

counteract the effects of the WTG hub support height.

As the WTGs were considered as a complete unit in regards of the impact to the antenna pattern ripple, de-tuning

would need to consider each WTG on its own to determine the individual impact on the antenna pattern. The

individual impact of each WTG on the antenna pattern has not been considered as part of this study.

An approximate cost of designing, engineering and implementing de-tuning circuits for each individual wind

turbine could be in the vicinity of $60k to $100k per WTG, possibly totalling $1.5M to $2.6M. This approach would

require ongoing maintenance and inspection to ensure suitable operational performance of the equipment.

Regular 3 yearly (triennial) inspections should suffice at an approximate cost of $1.5k to $3k per WTG (totalling $40k

to $80k every 3 years).

Whilst de-tuning WTGs could theoretically be done, the practicalities of implementing this option could be

challenging and expensive. BA is not aware of this being undertaken on WTGs in Australia or the effectiveness with

the rotating blades.

4.2.2 Power Increase

The AM Service operates using a 10 kW AM Transmitter and is operating at the maximum capacity of 10 kW. Any

increase in transmitter power would require a new transmitter, coupling unit and overall system validation and

upgrades for suitability.


An increase of 1.0 dB to the existing transmission facility is predicted to yield the following population figures in

Table 2. This is an overall increase compared to the current coverage predictions for the AM Service.

Crystal Brook AM Base Power to Mast

10 kW

Base Power to Mast

12.6 kW

Frequency (kHz)/Service Coverage Grade Existing Post WTG +1.0 dB

Power Difference

639 kHz – 5CK

Urban (10mV/m) 79,847 83,522 3,675

Suburban (2.5mV/m) 1,171,552 1,328,149 156,597

Rural (0.5mV/m) 339,403 182,731 -156,672

Total Population Covered 1,590,802 1,594,402 3,600

Table 2: Crystal Brook AM Post WTG and Power Increase Population Figures

An increase in transmitter power would be subject to ACMA interference checks and licence condition variation

approval. A publicity program would also be required to inform the affected audience during the upgrade.

Coverage prediction of an increase of 1.0dB to AM Service, post WTG installation scenario, is shown in Figure 6.

Figure 6: AM Service Predicted Coverage after the installation of WTGs and an increase of 1.0dB

An approximate cost of designing, engineering and implementing a transmitter replacement which would include

an ACU (Antenna coupling Unit) system upgrade whilst maintaining an operational standby AM Service would be in

the vicinity of $400k to $600k (capex).

There would be an increase in the power use associated with the upgraded facility. This is estimated to be about

$10k per annum (opex).


4.3 DTV Scatter Analysis

The impact to the DTV audience is predicted to be contained within a 2 km radius of the proposed WTG locations.

Whilst the population within this is scattered, there is still a predicted impact of 6 persons by the WTGs based on

2016 Census data. No major population centres are predicted to be affected by the proposed WTG locations.

4.4 DTV Remediation Options

There are currently two main options considered to remediate the predicted population impacted. Whilst not

exhaustive, the options presented are those that can be implemented practically and demonstrably have an impact

on mitigating the loss in population.

4.4.1 DTV Infill Facility

If there are a number of affected households, and the affected households are in close proximity of each other, a

cost-effective manner of serving the affected population is to establish a DTV Infill Facility. A DTV Infill Facility

targets a specific area and provides an alternative, local source of DTV transmission

The establishment of a new DTV Infill Facility would be subject to locating a suitable site, frequency allotments and

subsequent granting of broadcast licences. A publicity program to assist the affected population tune into the new

DTV Infill Facility would also be required.

An approximate cost of designing, engineering and implementing a new DTV infill facility would be in the vicinity of

$300k-$600k (capex) plus ongoing power and land tenure (opex). There would be an ongoing maintenance cost

associated with a new facility such as this which would be in the order of $20k to $50k per annum (opex).

4.4.2 VAST Receivers

If the affected population is small in number or are scattered such that a single DTV Infill Facility is not sufficient, an

alternative option is to provide Direct-to-Home satellite receiver installation using the Viewer Access Satellite

Television (VAST) platform. This service provides access to the equivalent services available to metropolitan

audience.

In order to receive the VAST service, appropriate documentation and equipment is required to be completed

before a VAST service is activated.

There is no ongoing fee for the use of the service apart from periodic maintenance of the receive equipment.

An approximate cost of designing, engineering and implementing a VAST receiver install would be in the vicinity of

$1k to $3k (capex) for a single outlet per household. The actual cost will be dependent on the location of the

household and number of receivers required.

5 Field Survey

It would be beneficial to conduct pre and post field survey measurements at key population centres and general

coverage locations to better qualify and attribute any reception degradation due to the Energy Park.

Broadcast Australia performs measurements in the field for the AM Service. The measurement locations for the AM

Service would need to be re-established prior to and following the installation of the WTGs as the signal levels

would potentially change. This will require a field survey team to visit the area and update these measurement

locations, an approximate cost for this work would be approximately $27k one-off (opex).


6 Electromagnetic Noise

An area of concern is the increase in the electromagnetic noise that would be generated in the installation of high

voltage and high-power electricity generation equipment. Neoen Energy would need to ensure that sufficient

power conditioning is built-in to the design of the infrastructure. Neoen Energy will need to demonstrate the levels

of electromagnetic noise, pre and post installation of the Energy Park, and ensure these do not affect broadcast

transmissions negatively. Neoen Energy must maintain these electromagnetic noise levels to an acceptable level

through the life of Energy Park.

AM is particularly sensitive to any increase in the noise floor and given the proximity of the Energy Park to the

Broadcast Australia’s AM facility, there is a concern about degradation to the quality of the service received by

listeners.

Whilst DTV by its nature has some form of resilience by way of error correction, it’s still susceptible to reception

issues due to an increase in the noise floor, as predicted by the DTV modelling tool.

7 Licenced Services

All the existing licenced services in the vicinity of Crystal Brook including communications/microwave links, 2-way

radio etc will need to be assessed to ensure no degradation is encountered. BA has not undertaken any

assessments on other users’ licences. The proposed WTGs should not obstruct, degrade or affect any of these

licenced services. It is expected that Neoen will be undertaking assessments of all licenced operators from all

facilities surrounding Crystal Brook.

8 Conclusion

The AM analysis shows due to the WTG installation, the impact to the HRP for AM is up to 0.7 dB reduction in the

direction of 332°T. The population drop is predicted to be 3,400 persons based on 2016 Census data. Predicted

maximum EME at the nearest WTG is an E-field of 2.7 V/m (0.1% of ARPANSA General Public Level) and an H-field

of 0.05 A/m (0.2% of ARPANSA General Public Level). The DTV impacted area is confined to within 2 km of the

proposed WTG locations. It is estimated that there is to be 6 people at risk of DTV scatter interference from the

proposed WTGs, based on 2016 Census data. It is recommended that Neoen undertake RF EME assessments

during the construction and operation of the Energy Park.

There are a number of remediation options presented in this report that Neoen is expected to add as part of the

conditions to the Energy Park build. These options are practical methods and means of alleviating degradation of

the reception of broadcast services from BA managed facilities. It is expected that remediation options would be

done in consultation with ABC and BA.

Pre and Post field survey measurements for AM and DTV services should be a requirement on Neoen to validate

the existing coverage quality is maintained post the Energy Park installation. BA can conduct these measurements

for Neoen and will need to re-establish AM measurement locations, pre and post installation of the Energy Park,

where the approximate cost is $27k.

Neoen is expected to undertake assessments to the electromagnetic noise and demonstrate that there is no impact

to the reception of broadcast services in the Crystal Brook general environs.


For assessments of impacts to other communications infrastructure, it is expected that Neoen will be undertaking

assessments of all licenced operators from all facilities in the vicinity of the Energy Park.

It should be noted that further analysis might be required if there are changes to the WTG parameters, numbers, or

location as the areas of scattering interference will change and would need to be further analysed. Increasing the

number of WTGs might also impact the overall coverage at the edges of coverage.

Any additional modelling or assessment works carried out by BA to determine the impact of the development of

the energy park at Crystal Brook, conducted either on behalf of the ABC or Neoen will be charged at cost plus a

25% margin to Neoen.

Documents

Issued: 18 March 2019 Crystal Brook Energy Park Study, SA · Generators (WTG) at Crystal Brook Energy Park (Energy Park). The BA Managed Services operating near the proposed WTGs