A Brace of Wind Farms

Windfarm Base

Following on from the successful completion of their Maesgwyn and Pant y Wal wind farms, Walters are pleased to announce the commencement of their third design and build wind farm in little over three years.

The wind farm, whose new site entrance is located just one mile from the Walters Hirwaun headquarters, is to be known as the Mynydd Bwllfa Windfarm and will comprise 9 turbines with a maximum tip to floor height of 125 metres. When connected to the grid, each turbine is expected to generate up to 2.5 MW.

The turbines are to be located at the top of the Rhigos Mountain which lies between the Aberdare and Rhondda valleys at an altitude of over 500m AOD – vertically some 300 metres above the new site entrance which Walters are currently constructing at its intersection with the busy A465 Heads of the Valleys Trunk Road. This extreme difference in altitude has provided one of the key challenges in designing the on-site roads.

Three principal constraints determined the design of the 4 km of access track and the similar length of on-site track:

  •  Turbine deliveries require maximum track gradients approximating to 1 in 10
  • Sustainability considerations required that the vertical alignment was developed to provide maximum recovery of excavated rock for use as road forming materials and
  • A relatively narrow land corridor provided restrictions with respect to horizontal alignment

Walters made full use of their in-house design department to engineer the proposed 8 km of access tracks within these tight constraints in order to optimise the roads construction. Additionally, the design and construction of the tracks and turbine bases needed to accommodate the various geotechnical challenges that presented. These included backfilled opencast mine workings, extensive peat bogs and abrasive sandstone deposits – all often occurring in the space of a few hundred metres.

The contract, including turbine erection and reinstatement, is expected to take up to 18 months to complete.