Chapter-2-Project-justification-and-background.pdf

8/14/2019 Chapter-2-Project-justification-and-background.pdf

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SunSouth 132 kV Power Project Final Initial Assessment Report

PARSONS BRINCKERHOFF 2136709C RPT003-E Page 2.1

2. Project justification and background

2.1 Need for network upgrades

2.1.1 Project in regional context

The Sunshine Coast region is experiencing significant population growth with an estimatedresident population over 320,000 people that is expected increase to over 420,000 people byyear 2026. For the period 2006 to 2026, the expected annual growth rate will be around2.4 per cent. A corollary of such growth is that the Sunshine Coast regions summer peakelectrical demand was 240 megawatts in 1999 but by 2009, this demand had grown to over400 megawatts, an increase in peak demand of around 78 per cent over this same period.

Forecasting by ENERGEX has determined that future residential and commercial growth inthe Sunshine Coast region will heighten load demand and ultimately require networkaugmentation to maintain network performance and security of supply. In the instance ofupgrades to high voltage powerlines above 66 kV, planning approval will be required underthe SPA .

ENERGEX has developed a Network Development Plan for the Sunshine Coast area whichidentifies the need for network augmentation comprising four new 132 kV substationsinterconnected by new and upgraded 132 kV powerlines.

For this Project, the proponent will pursue community infrastructure designation under theSPA, as the proposed developments will provide critically required community infrastructureto augment the existing electricity network in South-east Queensland.

2.1.2 Electricity network demands

The recent urban growth and enhanced lifestyle choices in South-east Queensland haveplaced significantly increased demands on the existing ENERGEX network. Various factorshave contributed to these demands and result from the existing and future expansion ofdevelopment within the region:

Volume of Demand: the increase in households, population, commercial and industrialdevelopment has meant that the network has been stretched to cater for ever increasingsupply demands. Demand is set to increase significantly in the region, which includes

both private development and State government initiatives for infrastructure projects. Changing Demand Patterns: the changing face of South-east Queensland has for some

time included a rise in the number of inner city medium to high density residential andmixeduse developments, and associated support networks such as retail, commercial,restaurants, community facilities and the like. Demand for power supply is increasing inmany areas, due in part to the proliferation of mixed use development, with demandtrending towards demand at all times of the day rather than the historical morning andafternoon peaks in power needs.

Changing Use Patterns: The typical household structure in South-east Queensland hasover time, changed to an increasing number of one to two person households, as hasthe pattern of power use. Commensurate with that trend, the relative cost of power hassteadily declined over the last few decades and, households now consume moreelectricity per head than ever before. This coupled with the affordability of household


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Page 2.2 2136709C RPT003-E PARSONS BRINCKERHOFF

fixtures such as airconditioning units and modern, larger televisions has drivendemand to all time peaks. This is expected to continue strongly over the next 10+ years.

Energy Conservation and Nonnetwork Solutions: The Sunshine Coast EnergyConservation Community was launched in March 2010 in partnership with SunshineCoast Regional Council, and was the first of its kind in Queensland. Qualifying residentsliving in the suburbs of Buderim, Mooloolaba, Mountain Creek and Sippy Downs wereinvited to help ENERGEX reduce peak demand through the installation of a simpleenergy conservation device on air-conditioners and pool pumps. These devices enablethe appliances to be remotely cycled by ENERGEX for short periods during peakdemand times, taking pressure off the network. The cycling technology has alreadybeen used in Australia and is in use in other countries overseas. To date more than900 devices have been installed, resulting in an estimated 1.2 MKW under theprograms control. In early November 2011, ENERGEX rolled out this programme to allcommunities on the Sunshine Coast.

Over the long-term, the move to a more sustainable use of the existing electricitynetwork through demand management initiatives such as the ECC program and theinstallation of domestic solar electric photovoltaic systems may enable ENERGEX todefer construction of new infrastructure. Notwithstanding, the proposed newinfrastructure scheduled for construction within the medium term planning horizon asdetailed in this report will be required simply to meet current growth in electricitydemand.

2.1.3 ENERGEX strategic network planning

ENERGEXs Network Strategic Development Plan in part aims to address the expectedneed to augment the sub-transmission network to meet the growing load demand ofSouth-east Queensland. It essentially provides a framework in which to develop theelectricity distribution network to maximise its economic life and assist in determiningappropriate locations of future infrastructure developments, as required.

Demand forecasts are an integral part of ENERGEX strategic planning. They are based oncompany and dwellings development forecasts to predict future performance and demandimpacts on electricity networks and also highlights potential constraints requiring attention.

Network security is the ability of the network to cope with faults without uncontrolled loss ofelectrical load throughout the network. The ENERGEX sub-transmission network is generally

planned on an N-1 basis, contingencies which provide the network with an alternative sourceof supply.

An effective N-1 capability is an important measure of security and is reviewed annually aspart of the development planning process.

The main purpose of the Network Development Plan is to:

identify future expected network limitations, grouping them as appropriate for resolutionthrough capital investment projects. A list of capital projects which address theseidentified limitations is then prepared, for the next five financial years on an annualrotating basis

provide estimates of resource requirements for the next five years prepare a network capital budget for the next five years.


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2.1.4 Network requirements

To comply with N-1 Network Security Planning requirements, ENERGEX needs to augmentits high voltage electrical distribution network in the SunSouth Power Project Area by the

construction of a new overhead 132 kV double-circuit powerline connecting the proposedBells Creek North, Birtinya and Palmview substations, via the Meridan Plains East substationto the Mooloolaba substation. This augmentation will address expected electricity securitysupply issues associated with future growth in the region, particularly in light of recentregional planning focus on growth in the Sunshine Coast hinterland.

2.1.5 Existing network and proposed upgrades

The factors influencing electricity network demand are relevant to the Sunshine Coast regionand the various infrastructure developments planned to occur in forthcoming years. Theultimate timing of electrical power demand within the Project Area is expected to vary and is

influenced by the following development factors:

The Queensland Government has land holdings south and west of CaloundraRacecourse which have recently been developed into large lot industrial estates.

DTMR is currently investigating a corridor for a future electric rail line proposed to linkBeerwah and Maroochydore via the Bells Creek area (known as the Caboolture-Maroochydore Corridor Study).

The Sunshine Coast Regional Council has outlined future urban development onundeveloped land in the Palmview Structure Plan area south of Sippy Downs.

The Meridan Plains Extractive Resources Area Master Plan prepared by the SunshineCoast Regional Council provides direction for the development of extractive resourcesin the Meridan Plains area.

The Sunshine Coast Regional Business and Industry Park is currently supplied by along 11 kV network. The area is forecast for significant industrial loading with expectedconsistent block load increases over the next 10 years. The existing ENERGEXCaloundra and Currimundi zone substations do not have enough capacity to supplysuch industrial load requirements.

The future development of the Sunshine Coast Regional Business and Industry Park

(Sunshine Coast University Hospital) precinct and increased growth around Kawanarequires an additional 132 kV injection at Birtinya to ensure a reliable and high qualityelectrical supply into the hospital and surrounding region.

The southern Sunshine Coast area is currently supplied by a single-circuit 132 kV ringextending from the Mooloolaba substation, progressively constructed in the mid to late1970s. The Bells Creek area, south of Caloundra, is estimated to cater for up to 50,000people in coming years. The predicted population increase has been determined byENERGEX to place additional pressures on the existing distribution network supplied by11 kV powerlines from the Mooloolaba, Caloundra and Currimundi 132/11 kV electrical zonesubstations.

ENERGEXs strategic planning models determined that the increased loads may lead tonetwork overload, thereby risking loss of power and creating quality of supply issues to


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customers and potentially compromising statutory reliability obligations unless augmentationof new high voltage electrical infrastructure is undertaken within the required timeframes.

Similarly, proposed planned development south of Sippy Downs is to significantly increase

residential dwellings in the area as a component of the Regional Development Areaspecified in the South East Queensland Regional Plan 20092031.

The Palmview Regional Structure Plan Area provides for the establishment of newresidential neighbourhoods predicted to establish 6,200 dwellings and up to 8,000 dwellingsand a retail/commercial gross floor area in the vicinity of 18,000 m 2 by year 2031 with anassociated residential population of 14,000 and up to 17,000 in the same period. This willproduce a total load in the order of 20 MVA to 25 MVA based on a load of 2.4 kVA perdwelling and 115 VA/m 2 for commercial/retail floor area. Such development necessitates anew 132/11 kV zone substation on the southern side of the Palmview development with adedicated double-circuit 132 kV injection.

ENERGEX identified in its 2004/5 review of the Network Strategic Plan a need for future132/11 kV zone substations at Birtinya, in addition to the proposed Bells Creek Northsubstation. ENERGEX recognised a need to de-load the existing 132/11 kV powerline atKawana as well as reduce the length of 11 kV feeders in the area to improve both the qualityand reliability of electricity supply to the region.

In addition to the proposed substations at Birtinya, Bells Creek North and Palmview,ENERGEX proposes to develop a fourth substation at Meridan Plains East which will be thecentral node for the proposed 21.5 km 132 kV powerline connecting Mooloolaba to BellsCreek, Palmview and Birtinya.

2.1.6 Network options

ENERGEXs existing 132 kV powerline ring between Mooloolaba and Caloundra is theextent of the regions 132 kV high voltage sub-transmission network. There are noENERGEX sub-transmission lines in the region available for consideration as alternativenetwork solutions. Therefore, limited network options necessitate the focus to be ondeveloping an effective augmentation strategy for the existing 132 kV line.

ENERGEXs Network Development Planning Department advised in November 2009 that noviable alternative network solutions were available from Powerlink Queenslands (Powerlink)transmission grid. Powerlinks current (or proposed) transmission grid does not comprise any

transmission lines that present any feasible augmentation opportunities that defer or removethe need for the Mooloolaba to Bells Creek North 132 kV network augmentation in theSunSouth 132 kV Power Project Area.

2.1.7 Non-network options

There are currently no non-network options to the proposed network augmentation; howeverthe Project has not yet progressed to a regulatory test. ENERGEXs planning proposalsassume an approximated establishment and operational cost of $300,000 /MVA per annumto defer capital works with a maximum load reduction of 3 MVA. Based on this assumption,the implementation of a network demand solution is not a viable option to the needs of thenetwork and was not considered in ENERGEXs Net Present Value (NPV) analysis.


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It is noted that ENERGEX has however implemented some non-network demandmanagement initiatives in the Mooloolaba, Mountain Creek and Sippy Downs areas(Sunshine Coast Energy Conservation Community) that despite being unable to reduce theneed for the proposed augmentation, may facilitate the deferral of a future proposed

Palmwoods to Mooloolaba reinforcement.

2.1.8 Network augmentation benefits

The primary benefit of the Project is that additional network capacity can be provided to meetfuture network reliability and security objectives resulting from anticipated demand growth.The following benefits will result from the proposed augmentation works:

load constraints will be relieved on the regions 11 kV network reliable energy supply can be ensured for Bells Creek North, Birtinya and Palmview

areas in line with predicted development and Regional Plan targets

ENERGEX will progressively continue to have the capacity to meet N-1 criteria an improvement of reliability and security of supply for residents and businesses in the

region the regions future growth in electricity consumption will be catered as population

significantly increases and usage patterns change.

2.2 Area selection process

In July 2008, Parsons Brinckerhoff was commissioned by ENERGEX to prepare an AreaSelection Report that presented investigations undertaken to identify all feasible powerline

corridor options that would enable a future 132 kV high voltage double-circuit powerline to beconstructed from the existing Mooloolaba substation to the future Bells Creek Northsubstation. The report was submitted to ENERGEX in November 2008, which recommendeda then preferred corridor option.

In January 2009, Sunshine Regional Coast Council released the Palmview Position Paperwhich identified future urban land use intentions within the Palmview Structure Plan area.Due to the release of the paper and further consultation with Sunshine Coast RegionalCouncil regarding updated ENERGEX network requirements, ENERGEX commissionedParsons Brinckerhoff to review the outcomes of the Area Selection Report (dated November2008) to include connections into its future Palmview and Birtinya substations.

The resulting Area Selection Report and Addendum was submitted to ENERGEX in August 2010. A copy of the Area Selection Report and Addendum is included in Appendix D.

Based on the comparative assessment undertaken and presented in that report, a preferredalignment option was identified that on balance had the least overall planning,environmental, social and economic impacts. The recommended alignment option (referredto as Option 3 in the above report) maximised the existing powerline easements andpotential refurbishment of existing infrastructure, reduced environmental impacts and wasmore consistent with the future urban development of the Palmview Structure Plan area anddevelopment of the Meridan Plains Extractive Resource Area.

While Option 3 was identified as the preferred powerline corridor option, issues of integrationwith infrastructure development, nature conservation, visual amenity and cultural heritagewarranted further study following acceptance of the preferred option by ENERGEX.


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These issues required further detailed investigation to determine and quantify likely impactsand mitigation measures and involved detailed environmental assessment and consultationfollowing the process as set out in the Guidelines about Environmental Assessment andPublic Consultation Procedures for Designating Land for Community Infrastructure, noted in

Section 1.7.1.

2.2.1 Process to identify corridor

The Area Selection Report and Addendum to the Area Selection Report utilised a constraintsanalysis for the study area involving both desktop methods and field reconnaissance. On thebasis of constraints identified through the constraints analysis, a preliminary corridor andBirtinya substation connection option was established.

Corridor options were developed in accordance with a framework of relevant legislation,policy and practices as well as taking into consideration aspects for relevant objectives and

criteria of a Sustainability Assessment Framework (SAF), specifically developed forENERGEX to provide an overarching framework to guide high-level decision making whenassessing possible network corridors. This framework is based on:

international sustainability initiatives sustainability frameworks reporting frameworks triple bottom line methodologies environmental management systems Australian industry best practice.

The SAF incorporates a Sustainability Assessment Tool (SAT), a tool for multi-criteriaassessment that enabled a differentiation between corridor options at a broad level utilising arobust and replicable sustainability assessment methodology based on environmental, socialand economic aspects.

The corridor options were developed taking into consideration aspects for relevant objectivesand criteria of the SAT that related to spatial constraints and opportunities in the study area.This included limiting impacts as far as feasible and being consistent with existing and futureland uses (including resource development and transport corridors), as identified in strategicland use planning documents, and minimising environmental impacts in relation tovegetation clearing.

2.3 Corridor options overview from area selection process

The following outlines a range of both supportable and non-supportable corridor options thatwere considered during the area selection process that culminated in the Area SelectionReport and associated Addendum Report which was submitted to ENERGEX in August2010 (refer Appendix D).

2.3.1 Unsupportable corridor options

2.3.1.1 Bruce Highway

A western alignment, co-locating the powerline along the Bruce Highway was considered.Potentially a corridor could make use of the existing road infrastructure corridor, following the


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Bruce Highway from the Mooloolaba substation to the south, turning east along Pierce Avenue.

Proposed commercial development and municipal infrastructure on the southern side of the

Sunshine Motorway in the Sippy Downs area significantly constrained any alignmentdevelopment to connect to the Bruce Highway corridor. Further, construction along the BruceHighway itself would also be technically difficult, particularly in terms of the extra length,easement acquisition and associated planning and social impacts of the line crossing intothe Palmview and Birtinya areas notwithstanding any potential constraint to future roadwidening schemes. Additionally, an existing 132 kV aerial powerline (F777/778) would needto be crossed by the proposed powerline adjacent to new residential development south ofBellflower Road, should this option be pursued. Key constraints were considered to be:

length/cost constructability conflicts with existing and proposed (major) infrastructure and future urban development conflicts with existing commercial and residential development in Sippy Downs and

Palmview conflicts with the Palmview Conservation Park and the Beerburrum State Forest possible need of an additional switching yard at Caloundra Road to provide injection

north to Palmview and Birtinya as well as south to Bells Creek North substation visual amenity impacts.

Due to significant construction constraints this option was not considered feasible and wasnot assessed further.

2.3.1.2 Sunshine Motorway

An eastern corridor, co-locating the powerline along the Sunshine Motorway and KawanaWay parallel and close to the existing 132 kV powerline (F804/1) was also considered. FromKawana Island Boulevard, this new line would traverse south to re-join the existing 132 kVpowerline (F804/2) at Premier Circuit, continuing south to the future Birtinya substation. Thisnew double-circuit powerline would then need to traverse west to the proposed MeridanPlains substation site at the corner of Rainforest Drive and Reservoirs Avenue in order toprovide injection into Palmview and Bells Creek North.

Construction along the Sunshine Motorway would be technically difficult, particularly in termsof the extra length, easement acquisition as well as the associated environmental and socialimpacts of the line crossing the Parrearra and Birtinya areas. Key constraints were

considered to be:

length/cost constructability conflicts with existing (major) infrastructure and future commercial and urban

development conflicts with existing commercial and residential development in Parrearra and Birtinya

areas conflicts with the Mooloolah River National Park and Mooloolah River environmental

regions visual amenity impacts.



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2.3.1.3 Sippy Downs

A potential option to duplicate the existing 132 kV double-circuit powerline (F777/778) southfrom the Mooloolaba substation along the eastern and southern boundaries of the University

of the Sunshine Coast before turning south and paralleling Sir Raleigh Drive was reviewed.This line would continue within the existing double width easement parallel to Sir RaleighDrive before crossing University Way and Sippy Creek to traverse to the centre of theproposed Palmview Development area. This proposed corridor was not considered feasibledue to the proposed future Palmview development and the need to retain the existing spareeasement capacity through Sippy Downs for future reinforcement to the Mooloolaba zonesubstation, if required.

Key constraints were considered to be:

length/cost constructability conflicts with existing and proposed infrastructure conflicts with existing commercial and residential development in Palmview visual amenity impacts.


2.3.1.4 Caloundra Mooloolaba Road (Corbould Way)

A corridor option was investigated that sought to entirely avoid the Meridan Plains Resourcearea, which is identified on the Sunshine Coast Regional Council Planning Schememapping. The resource area is generally between Caloundra Road and the Mooloolah River

in the middle of the Project Area. An option was considered that passed to the east andsouth of the resource area. By departing from the corridor at Meridan Way (associated withOption 3 of the Area Selection Report) and continuing south to the Caloundra MooloolabaRoad, turning west to travel on the northern edge of the Caloundra Mooloolaba Road to apoint where it crossed Westaway Road.

From there the alignment of this option continued along the southern boundary of Lot 8SP115552 to the western side of Lot 5 RP801895 and then continued to follow the samecorridor noted in the report as Option 5 to the Bells Creek North substation site. This corridorwas not considered feasible due to a range of issues.

A primary disadvantage of this option is that it would result in the effectiveness of the

substation at Reservoirs Avenue being substantially diminished. The need for this substationto be supported by a circuit of distribution lines making tee branches would result in a lessrobust network creating operational inefficiencies, potentially leading to quality of supplyissues.

Although this option would avoid a powerline being located within the resource area alongHoney Farm Road, which is identified as a haul route through the resource area, it is longerand more costly, would have required clearing of more vegetation (predominantly leastconcern regrowth west of Meridan Way) and would have encroached into an area along theCaloundra Mooloolaba Road that is proposed for a batter stability zone and visual screenbetween the Caloundra Mooloolaba Road and the resource area. Given these limitations,this option was not considered feasible and was not assessed further.


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2.3.1.5 Do nothing

In proposing this Project, ENERGEX also considered a do nothing option, however, thisapproach is not considered appropriate. As previously mentioned, the expected population

growth of South-east Queensland and particularly expected future residential development inPalmview, coupled with industrial and infrastructure development at Birtinya, Bells Creek andCaloundra South will result in high electrical load demand.

While it is possible that the rates of this growth may vary in the short-term, the networkaugmentation will eventually be necessary in the medium-term planning horizon.ENERGEXs Network Strategic Plan provides strategic planning guidance to facilitate TownPlanning and the timely acquisition of easements to reserve land in growth areas for futureelectrical infrastructure augmentations ensuring that optimal and efficient development of theelectricity network proceeds according to statutory and regional infrastructure strategicplanning requirements.

Additionally, under the Electricity Act 1994, the National Electricity Rules and the terms of itsdistribution licence, ENERGEX is obliged to reinforce or augment its existing distributionnetwork where necessary to ensure reliability of supply. As noted in Section 2.1.2, above,the forecast increased electricity demand in the area makes the proposed Project essential.

2.3.2 Supportable corridor alignment options

Once the broader routes had been considered, more detailed investigation commenced andthe Area Selection Report assessed in detail the following supportable corridor options.

2.3.2.1 Option 1 (north to south)

Option 1 of the Area Selection Report commences at the existing Mooloolaba substation andextends in a South-easterly direction to travel adjacent to Dixon Road, across the SunshineMotorway and then follows Claymore Road adjacent to the Mooloolah River National Park.

At the intersection of Claymore Road and University Way the corridor continues south totravel down University Way and crossed a stand of Melaleuca forest and into an open areaprior to crossing Sippy Creek. From Sippy Creek, the corridor heads south following a similarpathway to that of a proposed major road corridor (as illustrated on the Palmview PositionPaper) and intersected the site of the future ENERGEX Palmview substation.

From the substation site, the corridor followed a proposed major road corridor across Laxton

Road and ran adjacent to an unformed section of Westaway Road to cross across theMooloolah River adjacent to Westaway Road and link to a future ENERGEX Meridan PlainsEast substation near the intersection of Reservoirs Avenue and Rainforest Drive.

The injection point into the Birtinya substation site commenced from the future MeridanPlains East substation, and utilised the road reserve containing easement of the existingENERGEX F803 line and followed this to the intersection of Rainforest Drive and MeridanWay.

From this point, the new 132 kV single-circuit line corridor followed the northern boundary ofthe new Sunshine Coast Regional Councils sports fields (Lot 606 SP195889) until it turnedin a north-easterly direction along the eastern boundary of the Pacific Lutheran College.From there, it followed adjacent to the existing water and sewer easement in a north easterlydirection, crossing the future MMTC corridor and continuing until it intersects with theENERGEX F804/2 easement. From that point, the corridor was located on the western side


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of the ENERGEX F804/2 easement and traversed north until it connected into the futureBirtinya substation site on Lot 4 SP210782.

The corridor for the connection to the Bells Creek North substation commenced from thefuture Meridan Plains East substation and followed Honey Farm Road in a south westerndirection and continued along the entire length of Sattler Road before crossing CaloundraRoad and continuing in a South-easterly direction to link with Racecourse Road.

The Racecourse Road and Caloundra Road interchange was upgraded in 2007 to facilitate adouble carriageway for Racecourse Road, with a significantly widened road reserve.Depending on the availability of suitable land, the corridor could then traverse RacecourseRoad within the road reserve.

At the intersection of Racecourse Road and Pierce Avenue, the proposed corridor continuedin a southerly direction traversing Pierce Avenue and utilising the eastern road reserve ofRacecourse Road extension into the Sunshine Coast Regional Business and Industry Park.

A partial easement will be required over Lot 280 CG4920 which lies to the east of theSunshine Coast Regional Business and Industry Park. The proposed corridor for the firststage of construction terminates at the proposed Bells Creek North substation site (Lot 38)located at the corner of Racecourse Road and Fred Chaplin Circuit.


Option 2 noted in the Area Selection Report commenced at the existing Mooloolabasubstation and extended in a South-easterly direction to travel adjacent to Dixon Road,across the Sunshine Motorway. It then follows Claymore Road adjacent to the MooloolahRiver National Park following the existing ENERGEX F803 single-circuit 132 kV corridor tothe future Meridan Plains East substation near the intersection of Reservoirs Avenue andRainforest Drive.

The corridor for the injection into the Birtinya substation site follows the existing ENERGEXF803 line until the intersection of Rainforest Drive and Meridan Way. From this point the new132 kV single-circuit line corridor follows the northern boundary of the new Sunshine CoastRegional Council sports fields (Lot 606 SP195889), across a potential future Council roadconnecting into Woodlands Boulevard until it turned in a northerly direction to travel withinthe western boundary of the MMTC corridor. This corridor will cross Woodlands Boulevardand a north travelling on-ramp to the future motorway. The corridor continued north on thewestern side of the MMTC and at a point directly west of the Birtinya substation site turnseast to connect to the Birtinya substation site via South Road.

The corridor for the connection to the Bells Creek North substation commences from theMeridan Plains East substation and follows Honey Farm Road, paralleling the existingunderground water line to the north-west corner of Lot 8 SP115552. From there, it turned toa South-easterly direction crossing Lot 8 SP115552 diagonally to the north-eastern corner ofLot 5 RP 801895. From this point it travels south along the boundary line wholly within Lot 7RP913729, to cross Caloundra Road. The alignment then turns to the south-west andcontinues in a southerly direction adjacent to the alignment of Racecourse Road to terminateat the proposed Bells Creek North substation site (Lot 38) located at the corner ofRacecourse Road and Fred Chaplin Circuit.


Option 3 is the same as Option 2, except for the injection into the Birtinya substation site.For Option 3 the corridor follows the existing ENERGEX F803 line down Meridan Wayfurther than Option 2 and avoids the northern boundary of the sports fields within Lot 606


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SP195889 by crossing to the south of the proposed future sport field complex. The corridorthen turns in a northerly direction to travel within the western boundary of the MMTCcorridor, to north of Woodland Boulevard, before crossing the MMTC in a northeast directionuntil it links to the western side of the ENERGEX F804/2 easement and extends north until it

connects to the future Birtinya substation site on Lot 4 SP210782, via South Road.


Option 4 noted in the Area Selection Report follows the same as Option 3, except for theinjection into the Birtinya substation site. For Option 4 the corridor to the Birtinya substationsite departs from the ENERGEX F803 line approximately 1 km north of Rainforest Drive, andtravels in an easterly direction to link directly into the Birtinya substation site.


Option 5 is the same as Option 3, with the exception that between the future Meridan Plains

East substation at the corner of Rainforest Drive and Reservoirs Avenue and the northernboundary of Lot 5 RP 801895, the line follows the Westaway Road reserve south and thentraverses west along the southern boundary of Lot 8 SP115552 to the western side of Lot 5RP 801895.

2.3.2.6 Connection to Currimundi substation investigation

Following a preliminary review by ENERGEX of the corridor options developed above asthey relate to optimal network configurations, ENERGEX identified that it may bestrategically preferable to connect a future 132 kV single-circuit from Mooloolabatransmission substation into the existing Currimundi zone substation rather than a futureBirtinya substation.

To explore the range of issues associated with a potential connection to the Currimundisubstation instead of the Birtinya substation location, three sub-options were developed byENERGEX, that depart from a common location in all corridor options (except Option 4) toconnect to the Currimundi zone substation. These sub-options were compared with the basecase of connection into Birtinya substation.

Accordingly the Connection to Currimundi Substation investigation considered the fouroptions outlined below:

1. Option 1: base case Meridan Way (Rainforest Drive) to Birtinya overhead along

MMTC and Council sports field.

2. Option 2 A Meridan Way (Rainforest Drive) to Parklands and Saffron Drive toCurrimundi substation part overhead and underground. This alignment doubles theexisting single F803 circuit to Saffron Drive then underground to Currimundi.

3. Option 2 B Meridan Way (Rainforest Drive)/Caloundra Motorway to Grey Gum Placeto Creekside Boulevard then to the Currimundi substation by double-circuiting theexisting single-circuit F804, all as a new overhead powerline.

4. Option 2 C Meridan Way (Rainforest Drive)/Caloundra Motorway to SunjewelBoulevard then along Currimundi Creek to Currimundi substation, partially overhead

and partially underground. This alignment traversed a Council reserve and freehold landcontaining 'not of concern' vegetation at the headwaters of Currimundi Creek then


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underground along road opposite Currimundi Creek, winding its way into western sideof Currimundi substation.

These options were subject to comparative analysis by using the same methodology as

outlined in Section 2.2.1, including undertaking SAT analysis and scoring. The results of thisanalysis confirmed that Option 1 (the base case, involving connection to the Birtinyasubstation) retained an overall advantage considering a range of planning, environmental,social economic factors.

2.4 Further alignment alternatives

Consultation with key stakeholders including landowners and Sunshine Coast RegionalCouncil on the preferred study corridor commenced in early 2011. Outcomes of thisconsultation resulted in numerous minor alignment alternatives being suggested. Below is an

overview of the alternatives considered for each section of the Project. In addition, althoughsubmissions received during the first round of public consultation did not result in anychanges to ENERGEXs proposed alignment, additional clarifications and developments onthe Greenlink between Palmview and Birtinya have been included.

2.4.1 Mooloolaba substation to Meridan Plains East substation

A minor amendment was made to the alignment in this section of the Project on Lot 37C3147, to the north of the Mooloolah River. This amendment involves the alignment leavingthe existing road reserve approximately 215 m north of the Mooloolah River, to cross Lot 37C3147 to align with the existing powerline crossing of the Mooloolah River and with the

existing easement on the southern side of the Mooloolah River.

This objective of this amendment was to remove the need for two tension pole structures,and allow for a direct section of the powerline crossing of the Mooloolah River.

It is proposed to surrender the existing easements within Lot 37 on C3147 and revegetatethe area of the old easement and previously cleared but unmade road reserve parallel withthe Mooloolah River when the existing single-circuit powerline is removed.

Accordingly, the alignment in this section of the Project was amended as described above tobe further assessed as part of the IAR.

In Claymore Road between the southern end of the University of the Sunshine CoastUniversity and University Way (where Claymore Road turns due east) there were threedistinct options investigated for this 1.8 km section of the powerline. The three options were:

1. Construct the overhead double-circuit powerline in-situ on the same general alignmentwithin the western side of the road reserve. This option has been adopted pending thepossible ability to subsequently adopt Option C, provided the required road reserve andassociated approvals are sufficiently established before 2015.

2. Underground a new single-circuit powerline in road reserve, and retain the existingsingle-circuit overhead powerline. This was not favoured due to its very high cost and

future constraints it places on the ability to upgrade Claymore Road.

3. Construct the overhead double-circuit powerline on the eastern side of a widened roadreserve. This latter option, although preferred, is only possible if the decision to widen


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Claymore Road is made by Sunshine Coast Regional Council before 2015 andagreement is made in Councils scope to allow the double-circuit powerline to belocated on and within the eastern side of a widened road reserve.

An alternative alignment was considered by ENERGEX to locate the new double-circuit lineon the northern side of Claymore Road, from University Way to the eastern end of ClaymoreRoad. This included the installation of traffic calming devices around each pole structure dueto predicted minimal traffic flows on this road.

This option minimised the risk to the Sunshine Coast distribution network duringconstruction. Pending the width of alignment separation from the existing single-circuit lineon the southern side of Claymore Road, which varied between 11 metres (m) and 6 m, therewas a proportionate impact on the southern edge of the adjoining Mooloolah River NationalPark. Such an impact would necessitate a degree of vegetation clearing within the nationalpark to ensure the safe operation of the powerline.

Due to the protected and sensitive nature of this vegetation along this portion of ClaymoreRoad, this option was not preferred, as it would result in unacceptably high impacts to theecological values associated with vegetation that occurs along the southern boundary of theMooloolah River National Park.

2.4.2 Meridan Plains East substation to Palmview substation

Consultation with the owner of the land either side of the unmade road reserve betweenLaxton Road and the Mooloolah River indicated a preference for the Study Corridor to beamended from where it traversed the northern bank of the Mooloolah River to the proposedPalmview substation site.

The reason for the suggested amendment was to avoid the alignment constraining thepotential for the landowner to develop the land for resource extraction in the future, if theroad reserve was to be closed.

The amendment involved the alignment being moved from paralleling the existing unformedroad reserve that passes through Lot 2 RP 100145, to the eastern side of an existing SEQWater pipeline easement that runs in a north-westerly direction, across Laxton Road to thenorthern boundary of Lot 2 RP 100145. This alternative alignment then continued in a north-westerly direction to enter Lot 690 C311023. The alignment then traversed along thenorthern boundary of Lot 690 to a proposed alternative future Palmview substation site on

the north-east corner of the property.

The comparative impacts and benefits of this suggested amendment were considered, andconcluded that it resulted in comparative similar environmental impacts, however it had alesser impact with regard to constraining potential future land uses, than the adoptedalignment, provided the unmade road reserve could be closed. The issues included avoidingpotential future constrains on resource extraction and potentially avoiding any future conflictof a development of a road along the existing unformed road reserve.

Due to land acquisition issues, this alternative was not able to be pursued.


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2.4.3 Meridan Plains East substation to Bells Creek Northsubstation

Consultation with Sunshine Coast Regional Council indicated a preference for the alignment

south of Honey Farm Road to avoid Lot 7 RP913729, which was recently purchased byCouncil with the intention to develop the land for a regional sporting facility. Council indicateda preference for the alignment to remain associated with the road reserve and traverse southdown Sattler Road (on either side of a widened road reserve) to align with an identifiedcrossing point of Caloundra Road.

Councils proposed future Palmview infrastructure development schedule indicates that thereis no need to upgrade or widen Sattler Road reserve until 2021 or later pending the timing ofdevelopment for the initial 2,500 lots of the Palmview development. As the timing for aconnection to the Bells Creek North Substation is required by October 2014, ENERGEX isunable to delay the construction of this section of line to be integrated into a potential futurewidened road reserve.

For ENERGEX to undertake the Council suggestion, the powerline would come within closeproximity to residences along Sattler Road, and most probably requiring the resumption of ahouse and property on the eastern side of the road which ENERGEX would prefer not to do.

Although not a preferred alternative, ENERGEX subsequently offered to develop aMemorandum of Understanding with Council for a potential 50/50 cost share arrangementfor the longer term ability to relocate the (by then) operational powerline to an alternativeagreed alignment along Sattler Road. Such a relocation of the operational 132 kV powerlinecould only occur once the road corridor was upgraded to its ultimate configuration (notexpected before 2021) and an alternative powerline alignment secured within the upgraded

road alignment, by Council.Council subsequently suggested that it could possibly advance the acquisition of its widenedSattler and Honey Farm Road reserves ahead of its 2021 schedule and enable ENERGEXto build within the road corridor.

Any such alternative alignment would depend on Council securing a widened road reserveand all necessary permits and approvals to enable the construction of the powerline withinthe widened road reserve and relevant properties. To avoid delaying commissioning of thepowerline, Council would have to establish such an alternative alignment and resolve allassociated social and environmental issues by the time ENERGEX needed to commencedetailed design, scheduled (in this section) for late 2012.

Therefore, ENERGEX has confirmed with Council the need to progress with the acquisitionof a 40 m wide electrical easement for the full length of the western boundary of Lot 7RP913729 adjoining Lot 5 RP801895 and Lot 494 SP208091. This easement would thenextend across the north-western axe handle to join the powerline alignment from Lot 8 onSP115552.

Consultation was conducted with Racing Queensland with regard to the proposed alignmenttraversing along the western boundary of Lot 200 SP189338, this being adjacent toRacecourse Road between Caloundra Road and Pierce Avenue. As part of this consultation,Racing Queensland proposed the following alternatives:

locating the powerline in the centre of the median of Racecourse Road, betweenCaloundra Road and Pierce Avenue, being the frontage to the racecourse property

installing cable underground between Caloundra Road and Pierce Avenue


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locating the powerline along the western side of Racecourse Road where Crown landexists, so that public infrastructure could be located on public lands

utilising the proposed CAMCOS corridor to the east of the Racecourse.

These suggested alternatives were investigated, with the underground suggestion beingconsidered unfeasible due to cost. Locating the powerline on land to the west of RacecourseRoad involved impacting on Council owned Meridan Plains Nature Reserve, which due to itsconservation tenure was considered as having unacceptably high environmental impact.The option of utilising the CAMCOS corridor to the east of the racecourse was not a viablealternative, as it is located over 5 km to the east of the racecourse and traverses in a southwestern direction approximately 3 km south of the Bells Creek North substation site. Utilisingthis corridor to connect to the Bells Creek North substation was a very indirect approach,involving the powerline being significantly longer thus resulting in higher social andenvironmental impacts, as well as conflicting with a range of existing and proposed landuses.

It is relevant to note that ENERGEXs original concept in connecting into the Bells CreekNorth substation was to traverse down the centre of the median of Racecourse Road.The installation of street lights in the median strip down Racecourse Road south of Pierce

Avenue by the State Government precluded this option in this section of Racecourse Road,without replacing the existing street lighting.

ENERGEX has investigated the technical options of placing the new powerline down thecentral median strip of Racecourse Road between Caloundra Road and Pierce Avenue andare able to accommodate this from both an electrical distribution and construction viewpoint.

As a result, ENERGEX has requested information from Council relating to what constraintswould the location of the powerline within the median strip of this portion of RacecourseRoad place upon Council or the Department of Transport and Main Roads separable plansfor any upgrade or road enhancement in the area.

The alternative of placing three poles in the centre of Racecourse Road between CaloundraRoad and Pierce Avenue is the resultant recommended alignment in this portion of the StudyCorridor as it minimises the impact to the Corbould Park Racecourse property whilst notimpacting vegetation in the bushland nature reserve to the west of Racecourse Road.

2.4.4 Meridan Plains East substation to Birtinya substation

In July 2011, ENERGEX undertook consultation with Kawana Forest Residents Group.Feedback from this consultation were that due to some residents objecting to the proposedaerial alignment skirting the Meridan sports fields (on Lot 606 SP231205), if this alignmentwas chosen, then it should be undergrounded (or even in part parallel to the school).

The residents group preferred alignment in this area was to place the powerline within adeveloped east to west road reserve that would facilitate a future connection betweenPalmview and Sunshine Coast University Hospital, and if such an east to west publictransport connection did not proceed, ENERGEX should look at undertaking such analignment as a standalone infrastructure provider.

The option of an alignment that traversed the northern part of the sporting fields adjacent tothe school (Pacific Lutheran College) was considered during the area selection process(refer Option 2). Due to the close proximity to residences and the school, an alternative


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option that avoided passing close to these sensitive receptors and traversed around thesports fields was preferred.

The option of undergrounding the powerline in this area was assessed as being

unsupportable, due to the significantly higher cost and constraints it may place on futureinfrastructure providers.

2.4.4.1 Potential co-location within future Greenlink corridor

As referred to in Section 1.5.3, ENERGEX is aware of other proposed infrastructure corridorsbeing investigated within the Project Area for public transport purposes that may in futureprovide the opportunity for a powerline connection into the Birtinya substation to beco-located within this transport corridor, between Reservoirs Avenue and the future SouthRoad at Birtinya. The Sunshine Coast Regional Council was investigating the feasibility of aGreenlink or sustainable transport alternative to the private car between Palmview andKawana.

Subsequent to the issue of the Initial Assessment Report and at its Ordinary Meeting on22nd February 2012, the Sunshine Coast Council endorsed Option D as the preferredcorridor for the Palmview to Kawana Greenlink. Option D utilises Palmviews planned roadnetwork, then runs south in a gazetted road reserve, passing the south of the Ring Tankbefore connecting into Rainforest Drive. It then follows the route of the Meridan Sports Fieldaccess road and links to Kawana Way.

Councils endorsed Option D parallels and reinforces the proposed ENERGEX alignmentfrom the Palmview substation to the intersection of Rainforest Drive and Meridan Way.

At Meridan Way, the proposed upgraded powerline follows the existing high voltage singlecircuit powerline south, along the eastern side of Meridan Way to Kawana Way and theMMTC before turning east and paralleling the future motorway, as previously noted onSection 1.5.3.

To provide town planning and engineering certainty for the future electrical infrastructurerequired to facilitate the Birtinya development, ENERGEX proposes establishing the FinalCorridor as presented in Section 1.5.3. ENERGEX continues to pro-actively work withCouncil on its future proposals.

Both ENERGEX and Sunshine Coast Regional Council have agreed to continue workingtowards a shared outcome to minimise corridor impacts. ENERGEX have confirmed they arewere willing to investigate the suitability of surrendering the Final Corridor (once acquired)

and relocating to the shared Greenlink alignment, if that corridor was the preferred locationfor Greenlink, and provided the required corridor and associated approvals were sufficientlyestablished before the detailed design and construction of the powerline connection toBirtinya was required to commence.

Of the various corridors investigated by Council for the Greenlink proposal and for thevarious reasons noted above, only two would appear to be suitable to ENERGEX forco-location. These are:

1. The portion of the option from the northern end of Reservoirs Avenue to Kawana Waythat traverses a new corridor to the north of the Kawana Forest Estate, as shown inFigure 2.1. This corridor option is a highly attractive alternative for the ENERGEX132 kV high voltage powerline. Adoption of this alternative is only feasible if the decisionto proceed with this Greenway corridor is made by Sunshine Coast Regional Council by


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early 2015 and agreement is made in Councils scope of works to allow the double-circuit powerline to be located within and nominally on the northern side of the corridor.

and

2. The portion of the option from the southern end of Reservoirs Avenue, along RainforestDrive before diverting into Meridan Way to run south of the Meridan Sports Field toWoodlands Boulevard (the Final Corridor).

If the Rainforest Drive Greenlink option was successful, the existing road reserve may needto be widened. Assuming this widening was to be on the northern side, then the existingpowerline would need to be relocated. The most probable location for the new powerlinewould be in a new easement or potentially widened road reserve on the northern side ofRainforest Drive, approximately 20 m north of the existing 132 kV powerline alignment. Asimilar offset distance would be required on the eastern side of Meridan Way toaccommodate any road widening on that side.

The potential impacts of relocating the powerline to the northern side of Rainforest Drive andthe eastern side of Meridan Way within a new 35 m wide easement were assessed as part ofthe project scope. Due to perceived difficulties in easement acquisition negotiations, thisoption was not preferred compared to a rebuilding of the existing single-circuit 132 kVpowerline in-situ on effectively the same alignment (but which would inhibit future roadwidening). This alternative option, although preferred over the Final Corridor, is only possibleif the decision to widen Rainforest Drive is made by Sunshine Coast Regional Council beforedetail design commences (nominally early 2015) and agreement is made in Councils scopeto allow the double-circuit powerline to be located on the northern side of a widened roadreserve.

In the event that the Palmview to Kawana Greenlink as discussed above does not proceed,the suggestion by the Kawana Residents Group for ENERGEX to look at undertaking suchan alignment as a standalone infrastructure provider is unlikely to be supported.

During the area selection process an alignment across this area was considered (Option 4).This option included a connection into Birtinya that traversed in an east-west direction northof the Kawana Forest through the Birtinya Wetlands area.

After quantitative and qualitative analysis of options, this option was considered the leastfavourable option. This was largely due to the comparatively higher environmental impacts,including potentially crossing 600 m of endangered Regional Ecosystem 12.3.1 (Galleryrainforestnotophyll vine forest), the Birtinya Wetlands and associated habitat, andfragmenting a large intact endangered Regional Ecosystem and essential habitat areaassociated with the Birtinya Wetlands west of the Birtinya substation site.

During preliminary consultation with the Queensland Health regarding the construction of thepowerline in an easement on the southern side of South Street (southern end of theproposed Sunshine Coast University Hospital) within Lot 7 SP186336, ENERGEX wereasked to utilise a different alignment that avoided being near South Street but in lieudiagonally crossed the water body within Lot 7 SP186336. ENERGEX investigated thisalternative and identified that it had a potentially greater environmental impact. The waterbody is habitat for a range of water and migratory birds. The presence of conductors over thewater body would not only compromise the ecological integrity of the value of the habitat, itwould introduce an unnecessary risk of bird strike leading to fatalities to birds using thehabitat as well as placing the electrical network at greater risk.


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2.5 Underground cables

Underground cables were considered for some sections of the SunSouth Power Project. Onconsideration of a range of factors, which are discussed below, above ground powerline

connections are considered a more practical option than underground cables. This isprimarily due to issues relating to the construction and operational cost, environmental andmaintenance considerations as well as comparative electromagnetic field strengths aboveunderground cables.

Undergrounding of powerlines is more likely to be considered in new urban subdivisionswhere the cost is paid by the developer (and passed onto the future home owner) or wherethere is limited space to contain the new infrastructure. Undergrounding of the lowerdistribution voltage (11 kV or 33 kV) powerlines is much more affordable as they are of amuch less technically complex cable type than the higher voltage 132 kV powerlines.

ENERGEX is a monopoly utility governed by the Commonwealth economic regulator (the Australian Energy Regulator (AER)) which regulates both business expenditure and thereturns allowed to be recovered through electricity tariffs to the consumers. The AER viaassociated legislation and market rules govern to ensure that utilities such as ENERGEXpursue the most efficient development of its infrastructure.

At the high voltages used for distribution lines, the cost of undergrounding a line is generallya multiple of the cost of an equivalent above ground powerline, all other items beingequivalent and pending international cost of raw materials and suitable construction labourwithin Australia. The much higher project cost for such undergrounding would therefore haveto be recovered through electricity tariffs passed onto the electricity consumers, if allowed bythe AER.

Any proposed underground cable route present two possible construction methodologies:

conventional open trenching with the cable typically buried in conduit and the trenchbackfilled with suitable material where the natural soils are unsuitable

under obstacles such as creeks and across highly trafficked roads, directional drilling orunder boring is normally required which adds to the typical expense of such projects.

2.5.1 Cables

Underground high voltage electrical cables require specially manufactured cables typically

using high quality cross linked polyethylene (XLPE) insulation manufactured under extremesterile conditions to ensure cables can operate safely at high temperatures. This type ofcable utilises an extruded synthetic insulation. The raw material used for the insulation of thehigh voltage electrical cables comprises low-density polyethylene (LDPE). By virtue of itshomopolar character, polyethylene has a low relative permittivity, a very low power lossfactor and very high dielectric strength.

These high voltage, powerline cables are significantly more expensive to manufacture and join than those used at the lower distribution voltages such as 11 kV and 33 kV. From awhole of life cycle perspective, underground high voltage cable installation requires the useof a greater amount of conductor and consumes significantly more energy and resourcesduring manufacture and construction than an aerial powerline. Underground high voltagepowerlines are thus typically greater greenhouse gas producers than their aerial equivalent.For example, a modern overhead 132 kV pole line could be constructed using aluminiumconductors with a cross sectional area of around 500 mm 2 whilst an equivalent underground


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cable system would need copper cables with a cross sectional area in excess of 1,100 mm 2 plus associated extruded insulation.

Operationally, potential cost savings in electrical transmission loss reduction using

underground copper cables is small in comparison to the total cost of installing such highvoltage underground cable. Therefore, the potential operational lifetime cost advantages thatmay be obtained through any electrical transmission efficiency gains in using undergroundcopper cable is insignificant in comparison to the overall financial and environmental cost ofthe manufacture and installation of underground cables.

As such the potential of such efficiency gains is not a material differentiator in selectingbetween the two high voltage power supply transmission solutions of either overhead orunderground.

2.5.2 Cable joints (junctions)

Each high voltage underground electrical circuit comprises three cables, totalling six cablesin the ground. Cable drum lengths vary due to cable diameter but are typically about 700 min length. This length is dictated by the availability of appropriate machinery to handle theweight of the cable drums as well as considering the safety implications of handling.

Cable joint locations (junctions) need to be identified based on available constraintsconsidering the length of the available cable. At each junction of each separable circuit, therewill be three high voltage cable joints. The jointing of each of the cables can be up to 4 m inlength and almost 1 m in diameter, and each of these needs to be offset or staggered.The total area taken up by a series of three joints is a space approximating a typical seacontainer, waterproofed and buried in the ground. Joints need to be made in absolute sterileconditions minimising potential for moisture and dust to contaminate the jointing material.Pending the need and availability of imported materials, preparation and jointing of highvoltage cables may take many days to complete.

2.5.3 Environment considerations

Undergrounding of powerlines is highly disruptive to the environment typically requiring novegetation with roots longer than 150 mm able to be allowed to exist above the powerlinecable and no tall vegetation allowed to remain within the easement of an underground cablethat may have roots that could endanger the operation of the line. Noting that the easement

width required for this infrastructure type is typically less than the conventional widthsrequired for overhead transmission.

Generally no excavation or soil disturbance would be permitted above the undergroundcable, thus sterilising or significantly restricting any use of the area. In addition, the materialused to backfill the trenches is typically a highly processed, non-renewable stabilised fillmaterial.

Equally, such underground powerlines are highly susceptible to water intrusion and streamerosion during periods of flooding and any such powerline damage would take aconsiderable time to repair. In addition, once water entered a cable or cable joint, that portionof the cable may need to be replaced incurring significant downtime when the powerlinecould not be used. Alternatively, the aerial powerline enables the retention of lower growingvegetation, enabling environmental connectivity across the easement in sensitive habitatareas and are much more resilient to flood events.


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2.5.4 Road maintenance and upgrade

Where insufficient space is available to construct high voltage powerlines above ground,there is a preference to place underground high voltage powerlines within existing developed

and sealed road formations. However, such placement also places limitations on potentialfuture development or upgrading of the road where such development may cause differentialsettlement to occur around the powerline. Differential settlement caused to the powerlineespecially during earthworks compaction of the road material could stretch the cable causinga failure in the protective insulation.

2.5.5 Operational maintenance

From a maintenance perspective, damage to above ground powerlines is readily identifiableand able to be quickly returned to service should it be damaged in a major storm event suchas Cyclone Larry, in North Queensland.

This is not necessarily the case for an underground powerline, which may take some time toidentify the location of the fault. In the instance of Cyclone Larry, new high voltage structureswere installed and power returned to Far North Queensland within a few days of sufferingsignificant and widespread damage to the high voltage electrical network because of thisCategory 5 cyclone.

To facilitate the potential undergrounding of the distribution line a transition structure isrequired at either end, where the distribution line enters and then exists the ground. At thislocation the above ground to below ground transition occurs. Transitions structures can haveissues with fault occurrence at transitions from underground to aerial sections of the network,which creates increased risk to the network, and reduced reliability.

2.5.6 Electromagnetic fields

As explained in detail in the EMF assessment in Appendix L, and summarized inSection 7.17, modelling undertaken of a single-circuit underground 132 kV cable locatedadjacent to an existing single-circuit above ground 132 kV powerline under the ultimateloadings, indicate that localised magnetic fields directly above the underground cables arepredicted to reach up to 100 mG at a point 1 m above the ground. Whereas a double-circuitabove ground powerline operating under the same loadings are predicted to have magneticfields directly under the line of around 30 mG because of the greater separation distance

between the conductor and a point 1 m above the ground.

Chapter-2-Project-justification-and-background.pdf

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