An uneasy co-existence!
We all know that the sea is shared and its traditional shipping and fishing users have had to concede that offshore energy in its many forms, those dredging for aggregate and others, are encroaching on their traditional freedoms. But with the dash for sustainable energy from wind and tide are we placing too many constraints upon those who believed that the right to an innocent passage was not unreasonable?
In many areas of the world, offshore wind farms are now proliferating. Indeed, a chart of the proposed arrays to be erected around the shores of North Europe shows an extraordinary area of the shallower seas reserved for these developments. And while it might be suggested that the fact that they are mostly in shallow waters means that shipping will be unaffected, this cannot be assumed. Many are so close to shipping routes that diversions will be necessary, implying some additional cost, while many wind farm arrays are in such proximity to shipping that there are clear safety implications. If anyone doubts this, let them just take a look at the proposals for the German Bight, where there appears to be far more sea reserved for these energy producers than that for shipping or fishing.
For some time, the promoters of offshore wind and wave energy schemes seemed genuinely to believe that the prior claims of shipping or fishing were unimportant. And to do them justice, once they have been made aware of concerns, in many cases they have tried to adjust their plans to give more room to shipping. But it is at least an argument that they have tended to minimise the real safety concerns of shipping, that putting large numbers of obstructions in the sea close to shipping routes is asking for trouble.
A good illustration of what might possibly happen is encapsulated in the latest Safety Digest of the UK Marine Accident Investigation Branch. In one of the cases, the dreadful dilemma of a containership Master is recounted, after he became disabled in close proximity to one of these wind farms, which was under construction. The vessel, described as a a large container ship was nearing her arrival port, but was unable to restart her main engine after it had been stopped as part of a pre-arrival check. The anchor windlasses were also being prepared for arrival, but before the weight could be taken off the windlass gears, the vessel experienced a complete blackout, because the bow thruster, which the Master was hoping to use to regain some control of his drifting ship, had overloaded the generator. It was one of those chapters of increasing disasters which must make shipmasters into very bad sleepers.
And what made it infinitely worse, aboard a disabled ship with no means of dropping an anchor, the big ship was being carried at nearly two knots towards the wind farm. The vessel came within 2.5 cables of the wind farm, when it was possible to restart the bow thrusters, and fortunately, being a wind farm under construction, there were two tugs attending the work barge on the site. These were quick enough to put lines aboard and tow the ship clear, where eventually it was anchored. It could have been a very nasty incident indeed, involving serious damage and pollution. It is worth remembering the fierce tides that race around many of these offshore banks, and the strong winds that have attracted the wind farm promoters to these seas.
And in the same Safety Digest, lest anyone think that this is just an improbable accident, there was the case of a fishing boat that ran full tilt into a wind farm installation barge, when its skipper became rather too preoccupied by fishing. Let us not be alarmist, but suggest that these sorts of accidents may well, just like higher electricity bills, become part of the progression to more sustainable offshore energy.
Source: Watchkeeper