Between the Isle of WIght and Purbeck, to the south of a line from Durlston to St. Catherine's Point.  The map here shows the position.

Approximately 200 sq. km, or about the size of the whole of the Isle of Purbeck.

The developer is owned by Eneco Holding N. V., an energy company owned by 61 Dutch municipalities including Rotterdam, The Hague, and Dordrecht. More info here.

It is not known yet how many turbines would be used, but 133 to 333 is a reasonable estimate based on what Eneco has published. The number depends upon the individual power rating of the turbines, and the overall power output of the farm, neither of which has been fixed yet.  The turbines will be roughly 700-1000m apart.

The height of the turbines is unknown. A range of 150 to 205m (490 to 673 feet) is plausible. The only thing we know for sure (from Eneco's scoping report) is that Eneco stated a maximum height of 205m, and a maximum rotor diameter of 176m. To put this in context, Salisbury Cathedral is 123m tall, and the “Gherkin” in London is 180m tall – both less than the possible size of a Navitus Bay turbine. More info here.

It is much bigger than any operating offshore windfarm anywhere in the world. Until the middle of February 2012, the world's largest operating windfarm was off Thanet, but it has only a third of the power rating of the Navitus Bay proposal. The Thanet farm has 100 turbines 115m tall in an area of 35 sq. km, so it is much smaller than this proposal. Also, the Thanet farm is better located off a solitary headland, rather than in a bay, which reduces the length of coastline that it affects.  The biggest operating windfarm is now off the coast of Barrow in Furness. It is still significantly smaller than the Navitus Bay proposal.

The seabed zone for this windfarm was allocated by the Crown Estates, who benefit financially from the development.  Provisionally, the zone was chosen to be in Lyme Bay because that is a bigger area with fewer shipping movements and more shallow water, but the MoD exercise area prevented  the selection.  As a result, the zone was chosen to be here.

There are so many consultations these days that most people do not have time to contribute to them.  But this development is worthy of your attention.  Yes, your opinions will count, and there is still time to influence the outcome. Go to this page to see what you can do.

Yes, the turbines would be potentially visible from Portland to Ventnor – provided the weather conditions permit and you have an unobstructed view towards the farm. Because the coast is elevated along much of its length, and because the turbines are so tall, the curvature of the Earth has a limited effect on what you can see from the hills and cliff tops. Refer to the more detailed local descriptions of visibility for more information on this. Durlston Country Park, Durlston Bay and parts of Swanage would have the best views of the farm.

As an example, from Durlston, the farm may span over two and a half times the width of the whole Isle of Wight, and each turbine would appear to be over twice its height. Since the closest turbines would be only half the distance of the Isle of Wight, they would be visible more frequently than the island. From Bournemouth, although the farm is further away, the closest turbines would still look twice as tall as the Needles cliffs area. In short, the farm would be clearly visible whenever the weather permits, which is frequently in this area.

It is unlikely. For example, the Dutch government plans windfarms more than 24km from the coast (compared with 13km), and the German government, more than 30km (see also the comments here). At these greater distances, the turbines have much less visual impact. If you want to compare development areas across Europe, have a look at the 4coffshore.com database here.

It is planned with a 50 year lifespan, but it is likely to be re-equipped half way through its life. At that point, there may be a desire to use bigger turbines than those originally installed. At the end of its life, there will be provisions to decommission the site and return everything to its original state, although some disturbance to the seabed may remain depending on the type of foundation used.

Briefly, the area is poorly chosen in a region of great natural beauty, the proposed shape of the windfarm does not minimize its visual effect, and its scale is too large.  It also lies in an area of intense marine activity and high tourist attraction. See the longer discussion on this page.

It is very difficult to predict the economic effect of a windfarm because there are so many factors involved. Some people would almost certainly benefit from the windfarm, but others may suffer. Tourism is an important industry for the region, and there is a risk that it might be adversely affected. Prior experience with windfarms in other areas may not be helpful, as the Navitus Bay windfarm is much bigger than anything that has been built before so close to a major tourist centre.

Placing many obstacles in the open sea obviously decreases the safety of navigation.  However, the turbines are normally highly visible and will have navigation lights at night.  Search and rescue efforts may be hampered by the cluttering of radar returns, and helicopter operations close to the turbines would be more risky than out in the open sea.  These issues are common to all offshore windfarms but the high density of traffic, especially pleasure craft, and strong currents in this area amplifies the risks.

That is the current intention. However, there are safety concerns. The air inside the windfarm and downwind of it would be turbulent and variable when the farm is operating, which may affect yachts under sail. The tidal stream in the area is up to 2.5 knots, so loss of power inside the farm can quickly lead to a potential collision with a turbine tower (the blades are too high off the water to be a concern for most yachts). Furthermore, the water surrounding the turbines may be too deep for a small boat to anchor securely. Radar will be adversely affected by the farm, although GPS and VHF should work. It may be a bold skipper who decides to navigate the farm in a Force 6 on a Spring tide at night.  If you have any experience with GPS, compass and radar operations inside windfarms, we would be interested in your observations.

The scientific data on bird mortality and change in behaviour caused by offshore windfarms are incomplete.  Unfortunately, this proposal is on the line of an important migration route, so many different species, with different flight patterns, will traverse the area. It is possible to stop the turbines during times of migration, but predicting the correct times may be difficult. The effect of changes in mortality on populations depends hugely on the species.  For example, many seabirds are long-lived, slow breeders with few predators.  Even a small change in mortality rates can affect their populations.  On the other hand, small land birds tend to be short-lived, fast breeders with lots of predators, such as cats and cars.  Their populations would be less sensitive to a few turbine collisions.  Seabirds may actually benefit from the presence of windfarms because of improved fish stocks.  If you have any specialist knowledge of these issues, we would be pleased to hear from you.