As most European countries have procedures for hearings of interest groups, potential conflicts of interest are well known. Apart from various lobbying organisations, primary conflicts of interest concern: ship traffic, air traffic, defence and fishing interests.
Some areas may definitively be excluded from consideration for use for offshore wind power at the pre-planning phase. These are major ship lanes, areas close to airports, oil & gas pipelines, cable routes, raw material deposits, military restricted areas and areas of importance in relation to fauna, e.g. IBAs. However, most other suitable sites will confront a number of potential conflicts of interests with other uses and users of the locations.
The subject of ships is, according to the CA members [17], the most important subject in relation to conflicts of interest. The reasons for this seem to be the following:
ship lanes represent a siting limitation factor, as certain areas will be prohibited for use as offshore wind farms where established shipping lanes demand it. Furthermore, locations where ships may lay anchor to enter harbours, must be avoided.
offshore wind farms must be marked
properly and effectively, in accordance with national or international
guidelines (IALA 1984, IALA 2000 [xxiii]), however painting and illumination
/signal lights may have negative visual impact, which could lead to increased
public resistance (see Section 3.1.3).
As collision risk analyses for all offshore wind projects is a mandatory part of the EIA, valuable information is and will be available from these studies, see for instance background reports to [xiv] and [xvii]. [18]
Currently a large study and collision risk analysis is being carried out for the German Bight, and in general such risk studies and additional information on damage mechanisms are called for in order to investigate the issue of marine traffic safety and offshore wind farms more closely.
The main problem does not appear to be the civic air traffic, although certain areas will be prohibited by Civil Aviation Authorities, either national (CAA in the UK) or international (ICAO), for use as offshore wind farm sites where protection of air navigation demands this. Military issues incl. radar are dealt with in Section 3.2, below.
The requirements posed by helicopter teams seem to be the most important concern, e.g. rescue helicopter teams, who might have to access the offshore wind farms in heavy weather. As the sites are covered by quite heavy turbulence, helicopter manoeuvres within the area are difficult, making marking lights and ability to switching off all turbines immediately a serious safety issue.
In order to minimise the risk of collision with naval or air traffic, authorities put different requirements on blade painting and marking lights for the different countries involved. In most cases some kind of nacelle lights are required as a minimum, following the standards for onshore turbines and other high buildings.
In Germany, for instance, buildings larger than 100 m must have marking lights, and colours on the blades are mandatory for wind turbines larger than this size.
The use of good navigation equipment like radar and GPS [19] should make it less important to paint turbines in bright and shining colours. This issue has been a subject of negotiation for some sites, and is standard in other European countries.
In Denmark research is going on in order to find the most appropriate colour for towers, seen from a visual point of view the goal is to make the turbines appear as neutral as possible in relation to the surrounding nature.
The general conclusion is that turbines must be marked properly and effectively in accordance with national and/or international guidelines in order to minimise risk of collision with ships, low flying aircraft or helicopters. However, painting and illumination/marking lights may have negative consequences for the visual impact and increase the risk of collision with birds, both subjects resulting in the fact that the public acceptance of the farm may decrease. [20]
Therefore the safety issue should be well balanced with the environmental impacts, and the consequences of marking lights etc. on visual aspects and bird interests should be thoroughly investigated in the EIA.
Military area restrictions disqualify a number of feasible sites from being developed. Especially for Sweden and Finland this is considered problematic, as areas owned by the military cover a significant amount of the areas potentially used for offshore wind power. In both cases practical solutions for co-existence between military and wind power are called for, but a solution must come through the political system.
As an example of the importance of and need for political solutions, the British Ministry of Defence has objected to chosen sites on land and offshore as it is believed they would interfere with low flying aircraft, even though these sites were not in close vicinity to military airports or equipment, but apparently just due to the fact that the height of the turbines represents a danger in itself [xxiv].
Also the issue of disturbance of radio and radar signals has been a subject of negotiation in some countries, and in general the issue of radar is approached with much concern, as the disturbance of radar signal from offshore wind farms may become a serious obstacle to future development.
Based on result from preliminary Swedish studies [xxv] the following conclusions can be drawn, as an illustration of the potential problems and mitigations:
o the movements of the blades are registered by the radar as false echoes, giving rise to several dots on the operators screen, which may be confused with the echoes from an aircraft.
o For experienced radar operators this disturbance should be easily handled when the radar installation is not situated within the wind farm, and if the exact coordinates of the wind turbines are known, the radar system/operator should be able to compensate from the false signals.
o If the turbines are stopped, there will be no disturbance of the radar system.
As an example of measures to mitigate wind turbines effect on radar systems
and decrease the collision risk, it can be mentioned that in the UK, whenever
relevant, wind farms will be equipped with radar reflectors/intensifiers and
fog signalling devices, as specified by the Department of Environment,
Transport and the Regions [xvi].
However, the subject of radar a radio signal disturbance is still a key area of concern, e.g. in the UK where a BWEA working group has recently been convened to address the concerns of defence and aviation authorities collectively.
General conclusions:
It can be concluded that although solutions seem to be available, it will be important for the development of large-scale offshore wind farms that the subject of interference with radar and radio systems is more closely investigated, as the potential effects are system- or country-specific.
The conclusions from the following studies may contribute with valuable information:
A UK study carried out by Ministry of
Defence, undertaking a number of trials to determine the extent of interference
with radars from wind turbines, but these data have not been published yet.
A BWEA working group has been convened to address this issue.
The Swedish study concerning impacts on radar and radio systems will be finalised this year (2001).
Restrictions to fishing rights from offshore wind power are bound to be an area of conflicting interests as the fishermen will lose trawling ground and possibly areas for pot fisheries. Up to now this conflict has not excluded any projects from being carried through, but financial compensation must be given to the fishermen, often without much evidence that fishing is actually reduced. This conflict appears to be especially problematic for France, where the fishing lobby is very strong and do not hesitate to block harbours, if they feel their interests threatened, but such problems may also occur elsewhere since the fishermen are generally well organised all over Europe.
In order to minimise impacts on fish, and thereby reducing the risk of conflicts with fishermen, it is recommended to
avoid construction of wind farm in sensitive spawning areas, areas with species of commercial or conservation importance and areas with a very high value for fisheries
avoid construction during important breeding, nursery or feeding periods
carry out site-specific and species-specific monitoring studies in order to investigate the effect of offshore wind farms on fish, e.g. investigate if foundations may indeed serve as natural reefs, as indicated from previous studies (Vindeby), thereby increasing fish life, and investigate the consequences on fish population/fishing possibilities when fishing is restricted within and in the vicinity of the wind farm.
Ornithological associations are also a very strong lobby in most European countries, and negotiations are often carried out to define whether or not an area can be used for wind power.
In order to minimise potential impacts on birds and the resulting conflicts with ornithologists, the general conclusions about avoiding designated areas (including IBAs) and major migration paths should be followed. The layout of the farm and of the individual turbines (painting, illumination, size etc.) should also focus on minimising impacts on birds. Case studies/monitoring programmes should be carried out with the aim to investigate the effects of offshore wind farms on birds and bird populations, and furthermore generic studies concerning mitigating measures should be carried out.
The fact that not all Important Bird Areas have yet been officially designated, makes large-scale planning more difficult, and it should be in the interests of both the offshore wind turbine industry, ornithologists and EU/national nature protection societies and institutions that the borders of such areas are well-defined and well-known. Furthermore, guidelines for the proximity of an offshore wind farm to an IBA would be useful.
The siting of offshore wind farms may interfere with existing raw material deposits. As these deposits are well known already, this should however not lead to any significant conflict of interests. It is furthermore believed that offshore farms do not exclude extraction of, for instance, oil in the same area one CA member mentions that there may be possible synergies from simultaneous energy production in offshore wind farms and raw material extraction.
Seismic site surveys and historical records investigation during the planning phase prior to the decision of the exact location of the turbines should avoid possible conflicts of interest. Specific areas of archaeological interest should be avoided. If, however, for instance a wreck is found during installation, this may lead to a serious delay of the whole project. Measures must therefore be taken to avoid such incidents by carrying out the investigations necessary in the EIA.
The general conclusion is that conflicts of interest are restricted to areas already known in the planning phase, thus severe conflicts of interest which could stop a project can theoretically be avoided through careful, open planning. However, regarding radar no final conclusions can be drawn yet, calling for additional national investigations, as the disturbance effect may vary from country to country.