Maintenance

diagram only not to scale Maintenance the generator units are not normally manned and are remotely controlled each group of rotor units could be fitted with a current sheltered dock for workboats a helideck on each group will permit rapid evacuation of a casualty Stroma 3 security considerations may prefer inspection and maintenance access to be by helicopter only with no access being made available from the sea © clf anderson diagram only not to scale

Maintenance access roadways are installed during final commissioning Stroma 3 access roadways are installed during final commissioning equipment such as a mobile crane and HP water jetting equipment could be held on each group of generator units as required © clf anderson diagram only not to scale

diagram only not to scale Maintenance trash screens are self cleaning when the current changes direction Note: screen bars run horizontally not vertically as shown in this diagram the screens prevent access to the rotor by cetaceans, pinipeds and large fish each screen is designed to be easily lifted from its slot mounting and replaced inspection of underwater parts can be by ROVs (remotely operated vehicles) shellfish accretions can be removed using high pressure water jetting robots © clf anderson diagram only not to scale

© clf anderson diagram only not to scale Maintenance isolation gates open isolation gates closed conventional canal lock gates may be used isolation gates are moved at slack tide to allow maintenance on the rotor and the drive these gates would be kept closed until the unit is in place and fully commissioned power would then be immediately available to produce revenue © clf anderson diagram only not to scale

© clf anderson diagram only not to scale Maintenance isolation gates open gates may be made adjustable to control the entry flow isolation gates closed gate disk base top bearing high pressure water is pumped down the gate spindle to flush out grit and to lift the gate to allow it to be turned during slack tide reaction jets at the blade tips may be used to turn each gate floor of guide chamber these are the only underwater bearings in the whole device automatic gates can be used to close off the bypass channels © clf anderson diagram only not to scale

© clf anderson diagram only not to scale Maintenance this unit is in operation this unit is fully isolated if required, the isolation gates can be fully sealed using water bags to allow the water level in the guide chamber to lowered for extensive maintenance the water bags would be retained in place regardless of the state of the tide © clf anderson diagram only not to scale

© clf anderson diagram only not to scale Maintenance flow guides water-filled bags water bags alone may be used to isolate the rotor chamber thus saving costs © clf anderson diagram only not to scale

© clf anderson diagram only not to scale Maintenance the chamber may be provided with guide slots in the sides of the water passages isolation gates may simply be lowered into place when isolation is required high pressure water jets at the bottom edges of each gate will clear shellfish and weed from the guidance slots as it is lowered into place conventional canal lock gates may also be used © clf anderson diagram only not to scale