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CONSTRUCTION WORLD
FEBRUARY
2017
26
PROJECTS & CONTRACTS
“Our on-site monitoring of the application
involved spot checks on the surface
preparation, as well as Dry Film Thickness
(DFT) readings,” explains Mike Byrd, national
protective coatings specification manager,
Kansai Plascon.
Kansai Plascon had technical specialists
on-site for the project; successfully on
27 November 2015. The Protective Coatings
division has had prior experience with bridge
projects, which stood it in good stead in
clinching the Lesotho contract.
Byrd adds that the success achieved
with this particular project was also due to
Kansai Plascon’s 360° guarantee system,
which involves the end user, applicator and
the coatings manufacturer itself, all backed
up by dedicated aftersales support.
Plascotuff Epoxy MIO Intermediate
Coat is a two-component polyamide epoxy
containing micaceous iron oxide. It provides
a high-build barrier coating for protecting
steel in harsh conditions, and an abrasion-
resistant coat for shop-coated steel.
Plascothane 9000 Polyurethane Acrylic is
a two-component re-coatable polyurethane
acrylic high-performance finish for
maintenance and new construction, with an
excellent decorative appearance. It features
high gloss and colour retention, long term
protection and durability, and is available
in a range of colours. A high DFT can be
achieved with a single application.
The first foundation pour was finished on
30 June 2016 with employees from the
local community working tirelessly through
the days and putting in long hours. The
foundations used extremely low quantities
of Portland cement in the concrete
formulation of its wind turbine foundations.
In fact, these turbine foundations are the
greenest in the country, alongside Khobab
Wind Farm’s sister project, Loeriesfontein
Wind Farm.
Each turbine base has a diameter of
19 metres comprising over 45 tonnes of
reinforced steel. These turbine foundations
are utilising one of the world’s lowest
quantities of Portland cement in the
concrete formulation. Slag, a by-product
from the iron industry, is used to replace
89% of the cement. This has resulted in
what is believed to be, one of the world’s
lowest carbon footprints for any wind farm
foundation. “This revolutionary formula was
tested and successfully implemented by our
sister wind farm, so we were confident from
the onset to use the same formulation,” said
Kevin Foster, project manager for Khobab
Wind Farm.
Situated in the Hantam Municipality,
60 km north of Loeriesfontein in the
Northern Cape, Khobab Wind Farm
employs the majority of its labour from
the Loeriesfontein community, in support
of local employment and upliftment. “We
would like to thank the 100-plus local
workers who have ensured that our project
has continued to forge ahead on time, their
commitment is appreciated,” added Foster.
He continued saying, “As part of our
commitment to skills development and
community development, we have provided
local employees with transferable skills
training, which can be used at other
wind farms or other construction sites”.
The material excavated from the
foundation bases was of a good quality
and was subsequently re-used on site,
specifically for the wind farm road
construction and in the preparation of
the turbine hard stands, situated adjacent
to the foundations.
“In closing, we would like to once again
thank everyone on the construction team,
who worked diligently to complete these
foundations, from batching the concrete to
floating it,” concluded Foster.
The site was chosen because of its
excellent wind resource, its proximity
to national roads for wind turbine
transportation, the favourable construction
conditions, municipality and local
stakeholder support, the straightforward
electrical connection into Eskom’s Helios
substation approximately 11 km south of
the site, and studies showed that there
would be minimum environmental impact.
When operating at full capacity,
the Khobab Wind Farm will generate
approximately 563 500 MWh of clean
renewable energy per year; this is expected
to supply electricity to power up to 120 000
South African homes.
The majority of the 99 m turbine
towers are to be manufactured by GRI, in
Atlantis, in the Western Cape. Civil and
electrical works are to be completed by
a consortium comprised of Murray and
Roberts Construction and Consolidated
Power Projects.
The Khobab Wind Farm is part of the
South African Government’s Round 3
Renewable Energy Independent Power
Producer Procurement Programme
(REIPPP) is expected to be operational
by December 2017.
Wind farm completes foundations on time
Lesotho bridge
project supervision
The project required sand-blasting
the steel bridge surfaces to ISO
8501-1:2007. This was followed
by an application of a zinc-rich
epoxy primer, and two coats each of
Plascotuff Epoxy MIO Intermediate
Coat and Plascothane 9000
Polyurethane Acrylic.
Khobab Wind Farm has announced the completion of its final wind turbine
foundation. All 61 of its wind turbine foundations have been completed
ahead of the schedule, on 5 December 2016.
Mike Byrd, national protective coatings
specification manager, Kansai Plascon.