Careys Building & Civil Engineering was appointed as the Civil Balance Of Plant (CBOP) contractor to construct Bruckana Wind Farm which spans 678 hectares across Kilkenny, North Tipperary, and Laois. The scheme generates enough electricity to supply approximately 20,000 homes with renewable electricity.
The wind farm was a high-profile project and was the site of the Bord Na Mona Clean Energy Hub Launch in October 2013. Site logistics presented a considerable challenge due to the remote location and the tight timeframe of the project, requiring us to undertake special logistic planning to secure the supply of materials for the project.
The project involved construction of reinforced concrete (RC) turbine foundations, a permanent metrological mast, a 38kV electricity substation, a 38kV overhead transmission line, and an extension to the Lisheen substation that accommodates the grid connection of the Bruckana wind farm. Our team upgraded the existing road network to enable delivery of turbine components by constructing an off-site road and updating the M8 Junction 4 slip lane. We also constructed 11km of on-site roads, 15 crane hardstandings, and 14 RC turbine foundations. The required drainage included over 27km of swales and ditches, three permanent pumping stations, and drainage outflow from the site (monitored by Fisheries Ireland).
Throughout the works a variety of construction techniques were used to value engineer the project, providing the optimum solution for the client. Temporary and permanent road construction was carried out using traditional and floated road techniques throughout the site. Peat depths on site varied between 0.5m and 7m deep and therefore the 14 turbine foundations were constructed using soil exchange leanmix solutions and driven precast pile solutions. We worked closely with the Siemens Design Team in the design, construction, and post pour phases of the turbine base construction.
Careys worked with the client, WTG supplier foundation design teams value engineer and the 28 WTG foundation designs for the site, resulting in the construction of a mixture of soil exchange spread foundations and compression piled bases consisting of 52 precast piles, designed for a safe working load of 1006kn.
Each turbine foundation consisted of a monolithic 640m3 concrete pour carried out over 10 hours. Each pour consisted of 6 different concrete mixes and slump classes, and 70% GGBS was used in the approved design mixes to control the heat of hydration in the mass pours.
The site was subject to Bord Na Mona IPPC licences covering peat production and harvesting activities as well as comprising multiple conservation areas which required close monitoring throughout the works.
Our team team liaised closely with North Tipperary County Council, Kilkenny County Council, and the M8 maintenance contractor to ensure the works were coordinated successfully across both local authorities and the National Roads Authority. Given the remote location of the site, this co-ordination was essential in ensuring that materials could reach the construction site on time, preventing costly delays to the programme.
Throughout the works we worked closely with our consortium partner GaeltecKTL, as they are responsible for the Electrical Balance and Power (EBOP) package on site.