Editing Dynamic positioning (section)

==Comparison between position-keeping options==
Other methods of position-keeping are the use of an anchor spread and the use of a jack-up barge. All have their own advantages and disadvantages.
{| class="wikitable" width="100%"
|+ Comparison of position-keeping options <ref name=Intro/>
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| style=";width:33.3%;background:#efefef;" align="center"|'''Jack-up barge'''
| style="width:33.3%;background:#efefef;" align="center"|'''Anchoring'''
| style="width:33.3%;background:#efefef;" align="center"|'''Dynamic positioning'''
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!'''Advantages'''
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*No complex systems with thrusters, extra generators and controllers.
*No chance of running off position by system failures or blackouts.
*No underwater hazards from thrusters.
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*No complex systems with thrusters, extra generators and controllers.
*No chance of running off position by system failures or blackouts.
*No underwater hazards from thrusters.
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*Maneuverability is excellent; it is easy to change position.
*No anchor handling tugs are required.
*Not dependent on water depth.
*Quick set-up.
*Not limited by obstructed seabed.
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!'''Disadvantages'''
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*No maneuverability once positioned.
*Limited to water depths of 175 meters.
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*Limited maneuverability once anchored.
*Anchor handling tugs are required.
*Less suitable in deep water.
*Time to anchor out varies from several hours to several days.
*Limited by obstructed seabed (pipelines, seabed).
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*Complex systems with thrusters, extra generators and controllers.
*High initial costs of installation.
*High fuel costs.
*Chance of running off position in case of strong currents or winds, or due to system failures or blackouts.
*Underwater hazards from thrusters for divers and [[Remotely operated underwater vehicle|ROV]]s.
*Higher maintenance of the mechanical systems.
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Although all methods have their own advantages, dynamic positioning has made many operations possible that were not feasible before.

The costs are falling due to newer and cheaper technologies, and the advantages are becoming more compelling as offshore work enters ever deeper water and the environment (coral) is given more respect. With container operations, crowded ports can be made more efficient by quicker and more accurate berthing techniques. Cruise ship operations benefit from faster berthing and non-anchored "moorings" off beaches or inaccessible ports.