Aberthaw Tidal Power Station

2021 Outline Design by Edward Grist

(9) Operation and Maintenance

Contents
  1. Control Rooms
  2. Shore to Barrage load transit
  3. Preparing load for transit
  4. Load offload at Barrage
  5. Repair and Maintenance
  1. Control Rooms
    Data signals allow the monitoring and control of power generation, shipping, and security. This data is transmitted to each of two interconnected Control Rooms situated in a high-security zone above workshops at each end of the barrage (shown in yellow). This provides essential redundancy.
  2. diagram of Barrage with bascules raised
    Barrage with bascules raised to form a controllable dockside water level
  3. Shore to Barrage load transit
    Most day-to-day goods will be delivered using the roadway tunnels beneath a shipping channel after passing through shore-based security. Deliveries to barrage buildings or Machine Halls will then be made using the 5m wide peripheral access roads.
    Some items, including the very large, are able to be off-loaded onto the secure dockside area from a ship. Both of the shipping channels can be used for this purpose. The very largest, the two hundred and forty turbine-generator (T-G) boxes, have to be delivered to the Aberthaw dockside using the 54 metres wide shipping channel. T-G box deliveries will occur mainly during the barrage construction stage. Other large items can use this route throughout the operational life of the barrage.
    The special arrangement for T-G box delivery to the barrage is illustrated in the following figures. It starts at the land-based dockyard where the T-G box has been delivered. The 'baseplate' machine used to transport the MFU off the barge is in size, load carrying capability and speed of operation not unlike that of the tunnelling machine load used in the construction of the London Crossrail.
  4. Preparing load for transit
    diagram of preparation for transit 1
    Base frame loaded onto two barges diagram of preparation for transit 2
    Support platform added diagram of preparation for transit 5
    T-G box added


    diagram of preparation for transit 2
    Base frame firmly fixed to the barges diagram of preparation for transit 4
    Baseplate for T-G box added diagram of preparation for transit 6
    Ready for shipment to the barrage


  5. Load offload at Barrage
    diagram of load offload 1
    En route to the barrage


    diagram of load offload 3
    The ramp is lowered and an offload wedge is added. The T-G box is offloaded using dockside winches. The barrage crane then lifts the T-G box, the wedge is removed and the T-G box lowered onto the dockside.
    diagram of load offload 2
    The T-G box arrives in the shipping channel. Both bascules are then raised and the water level adjusted to the desired level by pumping in or out as appropriate. The two barges are secured preparatory to commencement of bascule offloading.
    diagram of load offload 4
    T-G box as delivered to the dockside of the Shipping Transit Channel


  6. Repair and Maintenance
    diagram of central Workshop

The Central Workshop and Dockside Workshop-Stores

Repair and maintenance activities are mainly carried out in the Central Workshop that is situated mid-estuary as shown. Work can also be undertaken in the store areas adjacent to the Aberthaw and the Minehead shipping channel docksides.
The Central Workshop has the capability of responding promptly to machinery breakdowns and provides a base for routine maintenance. Supporting this work are two main cranes - normally housed in dockside workshop buildings on opposite sides of the estuary.
The working floor in the Central Workshop is 18m wide and 70m long. Workshop maintenance and repair activities are carried out at barrage roadway level.