environmental statement - Rotherham's Online Application for ...

Meteorological Monitoring
2.17 Wind farm performance would be remotely monitored using a permanent
meteorological mast, the location of which is shown on Drawing
HJB/681/PA05, together with a System Control and Data Acquisitions
(SCADA) system that would monitor the individual turbines. Anemometry
equipment including wind speed and direction measurement equipment
would be positioned near the top of the mast on booms. The mast would
be up to 80m tall and a typical specification is depicted on Drawing
HJB/681/PA09. A slim-line lattice tower would be used. It is, however,
envisaged that the final choice of anemometer mast type would be agreed
through an appropriate planning condition, and presented in the CMS.
Turbine Foundations
2.18 It is proposed that reinforced concrete gravity foundations would be used
for the proposed turbines. This foundation type is typically an inverted T
shape consisting of a large square pad with a protruding upstand that lies
flush with the reinstated ground level. The excavation in which the turbine
foundation is cast would be backfilled with suitable stone, placed and
compacted over the foundation. The subsoil and topsoil stripped prior to
foundation excavation would be retained and reinstated around the base
of the turbine tower when backfilling has been completed. The turbine
towers would be connected to the foundation by a „foundation ring‟ cast
into the foundation, or alternatively by „holding down‟ bolts, again cast into
the foundation. Stability for the turbine is provided through both the weight
of the foundation and the material replaced and compacted over it. The
final foundation design will depend on the results from detailed ground
investigation, though it is currently expected that most turbines will not
require piled foundations. Although considered unlikely, detailed ground
investigation may reveal that piling or roch anchors may be necessary.
2.19 A typical turbine foundation is shown on Drawing HJB/681/PA11. Detailed
design specifications for each foundation would depend on site-specific
factors such as ground conditions, the specific turbine model selected and
various other engineering issues. Nevertheless, turbines of the size
proposed typically require a square concrete base with dimensions of
approximately 19 x 19 square metres. Including the protruding upstand,
the overall depth of the foundation would be around 3.5 metres. Each
turbine foundation would comprise up to 400 cubic metres (or 720 tonnes)
of concrete and approximately 40 tonnes of reinforcing steel. Following
construction of the foundation and the placing of the structural backfill, the
layer of subsoil and topsoil originally excavated from the turbine foundation
area would be reinstated.
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Penny Hill Wind Farm
Environmental Statement