Published by Energy Source & Distribution Nov/Dec 2015 edition. Or watch the project video: https://youtu.be/fe2t5oMsCOM

1. Overhead lines project keeps Queensland radio on the air
Bigger is better at
Lal Lal wind farm
When lightning struck and damaged
one of the transmission lines critical
for Broadcast Australia’s radio and
communications tower in Far North
Queensland, Zinfra mobilised a team to
the remote location in five days.
The works took four months and
involved the replacement of 6km of
conductor across 11 transmission
towers. Located 60km south of Cairns,
the broadcasting transmission tower is
at the top of Mount Bellenden Ker, the
second highest peak in Queensland. Not
only is the site remote, the rain gauge
at its summit records an annual average
rainfall of 8312mm, making it the wettest
meteorological station in Australia.
The broadcasting facility at the top
of Mt Bellenden Ker receives power
via an existing overhead high voltage
transmission line. The overhead line
is located on the eastern face of the
mountain, running from the Ergon
Energy HV network connection point at
the bottom station to the transmission
facility located at the top station.
The 22kV HV transmission line is
approximately 6km in length and
consists of overhead conductors
supported on a series of steel H-frame
towers. The line consists of the original
conductors and insulators installed in
the early 1970s, but the support towers
were replaced in 1997 due to heavy
corrosion. The facilities at the summit
are serviced by a privately owned cable
car, which runs almost parallel with the
22kV line and/or via a walking track.
project scope
Structure refurbishment
Given the tropical and wet conditions at
Mount Bellenden Ker, the transmission
line is vulnerable to the effects of the
environment and accelerated decay.
Broadcast Australia required inspection
of the tower structures to establish
trends in structural decay and to
determine the extent of structural
upgrade required.
Zinfra was engaged to inspect the
upper part of each tower within 4m
of the insulator attachment height.
Replacement of structural pins, bolts,
corroded items and the installation of
corrosion control measures made up
this portion of the works.
Re-conductoring of existing
overhead structures
Zinfra undertook refurbishment,
replacement, installation and testing of the
conductors, surge arrestors and insulators
on the H frame towers. In addition, Zinfra
supplied and installed a new earthing
system to each structure tower.
MAJOR CHALLENGES
Access, or lack thereof
The broadcasting facility is located
about 60km south of Cairns, on top of
a mountain, in the remote reaches of
Far North Queensland. Once on the
mountain, access to the towers is only via
the private cable car and by foot through
dense rainforest. The crew was required
to carry in all their tools, equipment and
supplies to complete the job.
Rain, rain and more rain
Wild weather was a hallmark of this
project. Wind, rain and poor visibility
made this work particularly difficult
and excluded the use of helicopters for
conductor stringing.
Outage windows
Minimising disruption to all Broadcast
Australia customer services was a
priority, so Zinfra was required to
undertake some of the works in limited
five-hour windows. Planning, resourcing
and timing were critical factors to deliver
under these circumstances.
Developers of the Lal Lal wind farm
near Ballarat, Victoria, are planning to
construct even larger turbines for the
project if changes can be approved.
Plans currently include turbines with
a height of 130m, however, WestWind
Energy has said it will apply to alter the
height to 161m.
The plans originally included 64
turbines between Yendon and Elaine,
but if the amended plans are approved
the number will be reduced to 60.
“In essence, what has happened is
turbine technology has moved in
the last five years to larger rotors but
only slightly bigger generator size,”
Westwind managing director Tobi
Geiger said.
“I can tell you honestly, if you were 2km
away and you saw a 161m high turbine
and then you drove further and saw
a 130m turbine from 2km away you
wouldn’t notice any difference. It is only
when you see them right beside each
other you see the difference. We think
the visual impact is minimal and probably
offset by having a few less turbines.”
The plans have sparked calls by local
residents for tighter noise controls,
arguing the new turbine blade sweep
area would increase by a 76 per cent.
But Westwind managing director Tobi
Geiger argued bigger turbines means
more energy would be generated, with
less noise.
“It should be noted larger wind turbines
are not noisier just because they are
larger,” he said.
“In fact in the last couple of years, we
have seen significant improvements
to wind turbine blade aerodynamics
compared to the technology that
was available when Lal Lal was first
approved.”
China eyes off $200m
Granville wind farm
Plans for a new windfarm in Tasmania
are looking more positive after the
developers visited investors and potential
partners in China.
WestCoast Wind is planning a 99MW wind
farm with 33 turbines just north of Granville
Harbour, a project it says will create more
than 200 jobs in an area ravaged by the
downturn in the local mining industry.
WestCoast managing director Alex
Simpson says he timed a recent visit
to China to coincide with an energy
roundtable held by State Growth and
Energy Minister Matthew Groom.
“This visit was extremely positive,”
Mr Simpson told Tasmanian media.
“The project was well received with
investors and provided confirmation the
Granville Harbour Wind Farm is located
in a world-class wind resource with good
project economics.”
Around 40 per cent of the potential
investors are in Australia, with the balance
offshore, largely in China.
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