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Wind farms (1 Viewer)

Tyke

Well-known member
Isn't the Geothermal plant up & running?:-

http://www1.eere.energy.gov/geothermal/hawaii.html

Seems the obvious solution for people living on a volcano!

"They're usually planted in an area that's already wasteland"

Heard that word before-it usually means anywhere with no houses or roads on it.

"There's a couple of non-starters for ya..."

Says it all.

Colin
 
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Ilya Maclean

charlatan
wind farms - facts, figures and emotions

Agree totally with what Alison says regarding need for hard fact over emotion, and have a couple of points to make.

Firstly, Alison - correct me if I'm wrong but I don't follow your arguments about Ferrybridge Power station requiring the entire country to be covered by wind farms to generate equivalent power. It generates 2 GW of energy. I’m fairly sure it is each turbine rather than an entire wind farm that generates 2 MW of energy. Therefore only 1,000 turbines would be needed, e.g. a square of c. 32 x 32 turbines. Spaced 500 m apart, that would require an area of only 16 km x 16 km (15.5 x 15.5 if the turbines are at each corner and you ignore the area taken by rotor blades). OK, maybe add a bit to that figure if you want to account for non-windy days and the fact that turbines keep breaking down, but still nowhere near John O’Groats to Dungeness.

Secondly, and partly in response to Mark Duchamp, obtaining the fact is easier said than done. I’ve been involved a great deal with the science of wind farm impacts on birds (I wrote the baseline report for the proposed Greater Gabbard Offshore Wind farm, the biggest offshore wind farm in the UK to date if it gets the go-ahead, and have worked a lot on collision risk modelling). The energy companies do give you quite a lot of grief and pressure to sway things their way, but nothing like the grief and pressure from JNCC and the RSPB (who review the reports) to swing it the other way! There are two key issues. (1) To what extent do wind farms result in bird mortality due to disturbance / displacement / habitat loss. (2) To what extent to the rotor blades result in direct mortality. The first is hard to assess, as it requires a thorough understanding of the extent to which displaced birds reduce the survival of birds in neighbouring areas (trust me this is near on impossible to work out). The second is hard to assess as even a very minor error (1-2%) in estimates of the extent to which birds avoid wind farms, results in estimates of mortality varying by 100 - 200%. Avoidance rates are very hard to measure as the entail observing birds when visibility is suitable, whereas most collisions are likely to occur in poor weather / visibility. The main point I'm trying to make with the latter is that view any estimates of mortaility with a great deal of skeptism!
 

Collster

Well-known member
Hi Ilya, welcome . What are your views with regards to windfarms built in the vicinity of schedule 1 raptors( with a very small uk population)? Seems it goes on in Wales, yet when you try to get answers from the local Council you are greeted with a wall of silence. I take on board what you say about mortality rates through collisions, but as you say its hard to measure, so figures could easily be higher than predicted couldnt they. My main concern with possible windfarms in this area is that all potential sites are going to impact on schedule1 raptors that hunt over the moors or forests. Just to accomadate these things huge tracts of forest has been clearfelled, displacing birds such as Goshawk. These birds are going to find it hard to gain another territory as other suitable areas are already occupied.With regards to the size of area needed for windfarms , you havent included the land area taken up by roads, quarrying and of course the miles of pylons
 

Tyke

Well-known member
Ilya Maclean said:
Agree totally with what Alison says regarding need for hard fact over emotion, and have a couple of points to make.

Firstly, Alison - correct me if I'm wrong but I don't follow your arguments about Ferrybridge Power station requiring the entire country to be covered by wind farms to generate equivalent power. It generates 2 GW of energy. I’m fairly sure it is each turbine rather than an entire wind farm that generates 2 MW of energy. Therefore only 1,000 turbines would be needed, e.g. a square of c. 32 x 32 turbines. Spaced 500 m apart, that would require an area of only 16 km x 16 km (15.5 x 15.5 if the turbines are at each corner and you ignore the area taken by rotor blades). OK, maybe add a bit to that figure if you want to account for non-windy days and the fact that turbines keep breaking down, but still nowhere near John O’Groats to Dungeness.

Secondly, and partly in response to Mark Duchamp, obtaining the fact is easier said than done. I’ve been involved a great deal with the science of wind farm impacts on birds (I wrote the baseline report for the proposed Greater Gabbard Offshore Wind farm, the biggest offshore wind farm in the UK to date if it gets the go-ahead, and have worked a lot on collision risk modelling). The energy companies do give you quite a lot of grief and pressure to sway things their way, but nothing like the grief and pressure from JNCC and the RSPB (who review the reports) to swing it the other way! There are two key issues. (1) To what extent do wind farms result in bird mortality due to disturbance / displacement / habitat loss. (2) To what extent to the rotor blades result in direct mortality. The first is hard to assess, as it requires a thorough understanding of the extent to which displaced birds reduce the survival of birds in neighbouring areas (trust me this is near on impossible to work out). The second is hard to assess as even a very minor error (1-2%) in estimates of the extent to which birds avoid wind farms, results in estimates of mortality varying by 100 - 200%. Avoidance rates are very hard to measure as the entail observing birds when visibility is suitable, whereas most collisions are likely to occur in poor weather / visibility. The main point I'm trying to make with the latter is that view any estimates of mortaility with a great deal of skeptism!

Hi Ilya-what an interesting post-weve been waiting for someone with your background!!
So with apologies for getting in before you respond to VB -hope you don't mind a few questions.

On your Ferrybridge numbers-surely a 2MW turbine only GENERATES 30% of it's gross capacity ( see BWEA website for estimated load factor) So to replace Ferrybridge' 1900MW of GROSS capacity ( load factor 40%) would take this number of 2MW turbines :-
2000 x .4 divided by 0.3 divided by 2 =1333 turbines. You get around 4 turbines per ha...so thats 333 ha-or 823 acres.

In view of your opinion that the displacement effect on wildlife is "near impossible to work out", and that avoidance rates & therefore collision rates are "very hard to measure"....what credance is to be placed on the EIA for any significant array of turbines in known breeding/assembly/feeding areas for wildlife?

Do you have a view on the failure to assess the cumulative effect of wind farms in a given environmental catchment ( as I understand it EIAs deal only with each location-which is how Planning authorities review them ). The xamples I have in mind are :-
* The proposals on the Isle of Lewis
* The burgeoning proposals in Northumberland ( see another BF thread on this)
* The proposals for Liverpool Bay-6 schemes in Planning which will total 2200MW...say 900 turbines in total.
* Thames Estuary, where Greater Gabbard may be joined by London Array , Thanet & Gunfleet to total 2000MW-say 800turbines.
* The idea floated by the Greater Gabbard developer Airtricity , that this scheme may become part of a line of a 2000 turbine super grid stretching to the coast of Holland.-how for example did your work on Greater Gabbard comment on the wider effect of these proposals?

Thanks
Colin
 

Ilya Maclean

charlatan
Hi Colin

You're probably entirely right about the required number of turbines and spacing. I'm not an expert on energy loadings. Was just trying to do a quick “back-of-envelope” calculation to make the point that the requisite for the entire the country to be covered by wind farms is pessimistic. Also, I know spacings are closer than 500 m (just took figure from original post).

I do claim to know more about EIAs etc though. The cumulative impacts point is a very important one. In some of the older EIAs it was almost entirely ignored, as each EIA was considered on its own merit. In the more recent ones the issue is given a fair amount of attention, largely due to pressure from EN/JNCC & the RSPB and the realisation that cumulative impacts will become increasingly important. My colleague who took the lead on this had no end of difficulties trying to assess this for the Greater Gabbard. There are two problems with it at present. Firstly, there are no uniformly adopted approaches (something very typical of EIAs generally) leading to widely different conclusion as to its effects. Secondly, cumulative impacts are very hard to assess for much the same reasons as it is difficult to assess the effects of displacement on bird mortality. SNH do offer some standard guidelines in a report they published (I have a copy if you want), but the report lacks detail on birds as it covers all aspects of cumulative impacts on wind farm EIAs. It also hasn't been in place that long (last revised April 2005) and its advice is not universally adopted. A PhD, funded by SNH at Glasgow University to look at exactly these issues has recently been advertised, so expect further developments in due course (although probably not soon enough). Hope this answers some of your questions.

Cheers

Ilya
 

Ilya Maclean

charlatan
In reply to valley boy.

See previous post about area - I know I didn’t take account of roads and pylons, but power stations have roads and pylons too! Actually my opinions on wind farms and raptors are mixed and lie outside my main area of expertise, which is offshore wind farms, so don’t take everything I say as gospel. The mortality rates could easily be higher as well as lower. Typically, as I understand it, a scenario-based approach is taken, with the worst case (as well as better) scenarios presented. However, there is also an additional level of uncertainty when dealing with raptors (also important for other species) as the extent to which they are moving through the area as opposed to being territorial as this also has a major impact on estimates of mortality. I couldn’t really comment on how realistic the facts and figures on raptors are though, except to emphasise the uncertainty. With regards to clear-felling forests for wind farms. Again mixed opinions. Other raptors - e.g. merlins and peregrines prefer more open areas, than goshawks and after all, goshawks are a partially introduced species. Not saying wind farms aren’t bad, and if wrongly sited are likely to cause high raptor mortality, but on the whole raptors have been doing fairly well since DDT banned. Also, climate change isn’t too great for birds either. I think I’ll sit on the fence when it comes to opinions…J
 

Tyke

Well-known member
"Hope this answers some of your questions."

Thanks Ilya-they are certainly honest answers!

I'm particularly struck by these comments:-


"The cumulative impacts point is a very important one..... There are two problems with it at present. Firstly, there are no uniformly adopted approaches (something very typical of EIAs generally) leading to widely different conclusion as to its effects. Secondly, cumulative impacts are very hard to assess for much the same reasons as it is difficult to assess the effects of displacement on bird mortality.....SNH do offer some standard guidelines in a report they published , but the report lacks detail on birds as it covers all aspects of cumulative impacts on wind farm EIAs. It also hasn't been in place that long (last revised April 2005) and its advice is not universally adopted."

My conclusion is that past & current wind farms have been & are being erected without any accurate knowledge of their effects on wildlife-particularly for birds.

The incidents at Smola are therefore not a surprise.

Thanks again for your honesty.

Colin
 
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Barred Wobbler

Well-known member
Tyke said:
Hi Ilya-what an interesting post-weve been waiting for someone with your background!!
So with apologies for getting in before you respond to VB -hope you don't mind a few questions.

On your Ferrybridge numbers-surely a 2MW turbine only GENERATES 30% of it's gross capacity ( see BWEA website for estimated load factor) So to replace Ferrybridge' 1900MW of GROSS capacity ( load factor 40%) would take this number of 2MW turbines :-
2000 x .4 divided by 0.3 divided by 2 =1333 turbines. You get around 4 turbines per ha...so thats 333 ha-or 823 acres.

In view of your opinion that the displacement effect on wildlife is "near impossible to work out", and that avoidance rates & therefore collision rates are "very hard to measure"....what credance is to be placed on the EIA for any significant array of turbines in known breeding/assembly/feeding areas for wildlife?

Do you have a view on the failure to assess the cumulative effect of wind farms in a given environmental catchment ( as I understand it EIAs deal only with each location-which is how Planning authorities review them ). The xamples I have in mind are :-
* The proposals on the Isle of Lewis
* The burgeoning proposals in Northumberland ( see another BF thread on this)
* The proposals for Liverpool Bay-6 schemes in Planning which will total 2200MW...say 900 turbines in total.
* Thames Estuary, where Greater Gabbard may be joined by London Array , Thanet & Gunfleet to total 2000MW-say 800turbines.
* The idea floated by the Greater Gabbard developer Airtricity , that this scheme may become part of a line of a 2000 turbine super grid stretching to the coast of Holland.-how for example did your work on Greater Gabbard comment on the wider effect of these proposals?

Thanks
Colin


Colin. I'm dipping into the board to post for the first time in about a year just to correct a minor but significant detail in your reply.

You'd get about 4 turbines to the square kilometer (possibly 1 0r 2 more), not 4 to the hectare, as I'm sure you realise, so for 1333 turbines you would need 330 square kilometres or 129 square miles. A huge area.

I also believe your load factor for a major coal station to be low at 40%. the industry always worked on 70%, but you may have more up to date figures on this than I have, specific to Ferrybridge.

Working at 70% these figures would increase to 2,333 turbines, requiring 583 square kilometres of land.

Ilya also stated that conventional power stations require roads as well as wind farms do, but a conventional power station gets by with a mile or two of road. A windfarm of 583 square kilometres with turbines spaced in rows 500m apart taking up a square of 24 km on a side (assuming this is possible and there are no topographic reasons why they cannot be spaced so tightly - highly unlikely in practice) would require service roads stretching 1159km in total, or 720 miles of 5m wide track or road. A large area of land (6 square kilometres) as well as material, further fragmenting the habitat.
 

Ilya Maclean

charlatan
Quoting from the BWEA website:

"A typical wind farm of 20 turbines might extend over an area of 1 square kilometre, but only 1% of the land area would be used to house the turbines, electrical infrastructure and access roads; the remainder can be used for other purposes, such as farming or as natural habitat".

Leave others to do the calculations....

Cheers

Ilya
 

Barred Wobbler

Well-known member
Ilya Maclean said:
Quoting from the BWEA website:

"A typical wind farm of 20 turbines might extend over an area of 1 square kilometre, but only 1% of the land area would be used to house the turbines, electrical infrastructure and access roads; the remainder can be used for other purposes, such as farming or as natural habitat".

Leave others to do the calculations....

Cheers

Ilya


I bow to you the expert and return to my exile. However I would point out that the BWEA are reknowned for their selective use of facts. To use only the footprint of the tower as a basis for land use is disingenuous in the extreme and you would get nowhere near 20 of the large 2 and 3MW turbines that are being erected these days in one square kilometer. Go out and look for yourself and do not leave others to do the calculations.
http://www.stopturbines.com/
Farewell.
 

Steven Astley

Well-known member
More and more greenbelt land is being eaten up by out of town shopping centres, sport centres, cinemas etc. often on SSSI

They abuse space and encourage yet more car useage with there massive carparks and lack of provisions for public transports.

So I find hard to protest against a renewable energy source on the grounds of local loss of habitat. When they are much worser less worthy building schemes abusing this.
 

Tyke

Well-known member
Steven Astley said:
More and more greenbelt land is being eaten up by out of town shopping centres, sport centres, cinemas etc. often on SSSI

They abuse space and encourage yet more car useage with there massive carparks and lack of provisions for public transports.

So I find hard to protest against a renewable energy source on the grounds of local loss of habitat. When they are much worser less worthy building schemes abusing this.


But they don't build Tesco Stores or Cinemas on pristine upland peatlands....well not yet anyway.

But they do build wind farms in such places.

I don't see much difference in the "worthiness" of either.

Colin
 

Tyke

Well-known member
Ilya Maclean said:
Quoting from the BWEA website:

"A typical wind farm of 20 turbines might extend over an area of 1 square kilometre, but only 1% of the land area would be used to house the turbines, electrical infrastructure and access roads; the remainder can be used for other purposes, such as farming or as natural habitat".

Leave others to do the calculations....

Cheers

Ilya

Now you worry me Ilya.

One-this is innacurate-look at the turbines per unit area for any built assembly of significance.

Two-the whole area swept by the blades, and occupied by the infrastructure presents disruption & potential barrier to its erstwhile native inhabitants.The peatland communities- plants & inverts-have been DUG UP-& replaced by concrete.Is this not an adverse environmental impact? Would you not include it in any report you prepared? By the BWEA definition, you would calculate the area of a forest from the total cross section of it's tree trunks & ignore the canopy!.

Colin
 
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Tyke

Well-known member
Alan Seaton said:
Colin. I'm dipping into the board to post for the first time in about a year just to correct a minor but significant detail in your reply.

You'd get about 4 turbines to the square kilometer (possibly 1 0r 2 more), not 4 to the hectare, as I'm sure you realise, so for 1333 turbines you would need 330 square kilometres or 129 square miles. A huge area.

I also believe your load factor for a major coal station to be low at 40%. the industry always worked on 70%, but you may have more up to date figures on this than I have, specific to Ferrybridge.

Working at 70% these figures would increase to 2,333 turbines, requiring 583 square kilometres of land.

Ilya also stated that conventional power stations require roads as well as wind farms do, but a conventional power station gets by with a mile or two of road. A windfarm of 583 square kilometres with turbines spaced in rows 500m apart taking up a square of 24 km on a side (assuming this is possible and there are no topographic reasons why they cannot be spaced so tightly - highly unlikely in practice) would require service roads stretching 1159km in total, or 720 miles of 5m wide track or road. A large area of land (6 square kilometres) as well as material, further fragmenting the habitat.

Hi Alan-nice to hear from you again. Thanks for looking over my shoulder.
Yes-I screwed up-too fast on the keyboard without thinking!!. Ha should be Sq Kms.

RE: Ferrybridge load factor-this is my reference :-

http://66.249.93.104/search?q=cache...rybridge+load+factor&hl=en&gl=uk&ct=clnk&cd=3

Cheers
Colin
 

Steven Astley

Well-known member
Tyke
Bolton Wanderers Reebok Stadium and adjoining shopping centre was built on SSSI mossland.
A local housing development destroyed beech woodland that had wood warblers, redstarts etc that can not be replaced overnight.
huge carparks, shopping centres have a more detrimental affect on the local enviroment than wind farm buildings.
 
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Ilya Maclean

charlatan
Wasn’t trying to make any value based judgement or make a controversial point by posting the quote and I certainly wasn’t implying anything about impact due to basal area of turbines and implying anything by not doing the calculations. Was literally just quoting the website to give a rough figure of turbine densities and leaving the calculations to others because I was about to leave the office. Also, I don’t work on onshore wind farms, only offshore ones where peat loss etc is less of a problem. I don’t like basing judgements on half baked evidence, and tend to refrain from doing so. However for what its worth my own thoughts are this (pleased bare in mind that I haven’t researched any of this very carefully – a lot less carefully than I would for a report anyway!)

(1) wind farm turbine densities – I’ve never sat down and worked this out, nor have attempted to research this, but having seen a lot of wind farms, particularly offshore, 4 turbines per square kilometre seem a little low, and 20 nearer the mark, but probably a little high. Might have missed it by skim reading, but didn’t notice the http://www.stopturbines.com/ website saying anything explicitly about turbine densities, and with a name like that could also likely to be at least as biased as the BWEA website.

(2) Impacts due to presence of structures. These are likely to be entirely species dependent and may also change through time due to habituation. Small passerines such as meadow pipits etc that typically fly below the rotor blades are probably not that badly affected except due to the loss of habitat at the base of the wind farm including the concrete structure, which as I understand it covers much less of an area than the rotor blades sweep, and thus the analogy to forest canopy isn’t entirely correct. Not an expert on onshore wind farms though and anybody wishing to know more would do well to check Steve Percival’s reports and other publications. Larger species – divers / scoters etc at sea and raptors on land are badly affected over entire wind farm and Danish studies such as that by my friend Ib Krag Petersen show that displacement can occur in a buffer zone up to 4 km or more from the wind farm itself.

(3) Roads etc – will be wind farm dependent as the layout of wind farms is not universal, but will obviously result in some habitat loss. Disturbance due to maintenance traffic, particularly offshore for sensitive species such as divers and common scoter is also a problem.

(4) Climate change is also a major problem for birds. Have a quick look at http://news.bbc.co.uk/1/hi/sci/tech/3879841.stm, or have a look at Sarah Wanless’s many publications on the catastrophic declines in seabirds due to climate change if you want the full un “popularised” story.
 
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bkrownd

Well-known member
Tyke said:
Isn't the Geothermal plant up & running?:-

http://www1.eere.energy.gov/geothermal/hawaii.html

Seems the obvious solution for people living on a volcano!

There is one geothermal plant. Sometimes it even runs near full capacity.
The other geothermal project was protested by angry residents, and finally
IIRC their land was bought out. One of the problems with the geothermal
projects is they were trying to drill them in undeveloped forest near housing
subdivisions. (The active volcano has some of the most heavily populated areas
of the island.) Power generation is always a heavy industry, with the associated
headaches. In the case of geothermal, it is a mining industry, and you know
how popular those are.

Most of the wind farms are located on ranch land where the native habitat was
annihilated long ago. They're small beans now, but expanding. The major
criticism of the wind farms so far has been that people don't like to see the red
aircraft hazard lights in their precious viewwwww. :stuck: Cows don't care about
the view, and ranchers like the extra money. Out of sight, out of mind.

I don't know if the wind farms will ever surpass the geothermal plant, but there
is plenty of ranch land to plant them on. Both together might...or might
not...someday come near the capacity of the traditional oil-fired plants.
Probably not, since energy demand is growing very very fast here.
 
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Tyke

Well-known member
Steven Astley said:
Tyke
Bolton Wanderers Reebok Stadium and adjoining shopping centre was built on SSSI mossland.
A local housing development destroyed beech woodland that had wood warblers, redstarts etc that can not be replaced overnight.
huge carparks, shopping centres have a more detrimental affect on the local enviroment than wind farm buildings.

Sure thing-all bad news!
Colin
 

Tyke

Well-known member
".... I don’t like basing judgements on half baked evidence, and tend to refrain from doing so. However for what its worth my own thoughts are this (pleased bare in mind that I haven’t researched any of this very carefully – a lot less carefully than I would for a report anyway!).....but having seen a lot of wind farms, particularly offshore, 4 turbines per square kilometre seem a little low, and 20 nearer the mark,": Thames Array -270 turbines/ 245 sq kms. = 1.1 per Sq. km

Greater Gabbard-140 turbines / 102 sq. kms. = 1.4 per sq. km

Source- The Crown Estates website.


"Larger species – divers / scoters etc at sea and raptors on land are badly affected over entire wind farm and Danish studies such as that by my friend Ib Krag Petersen show that displacement can occur in a buffer zone up to 4 km or more from the wind farm itself."

Then I sure hope you & your counterparts know what you're doing & saying in the Thames Estuary EIAs.....but on the basis of these conversations it's hope rather than confidence.


"Climate change is also a major problem for birds"

Now then Ilya-of all the comments you have made this worries me most.
Yes of course climate change affects all species.That is not in dispute.
What is in dispute though is whether building wind farms in environmentally sensitive sites in UK ( & given the inadequate means of measuring their local environmental effect which you have identified) will make one jot of difference to climate change.
Therefore the equivalence which your statement implies between avian mortality resulting from wind turbines, and that resulting from climate change is very much to be questioned.
If you were an employee of a company with commercial interests in wind farms -of course I would understand completely your motivation for asserting that avian mortality from wind farms is justified because it will reduce that from climate change.
But I don't understand the relevance of this controversy to your stated involvement in attempting to produce balanced & accurate EIAs for offshore wind farm proposals.

"...after all, goshawks are a partially introduced species."

This is from your reply to VB Ilya which I have just re-read. Are you saying that Goshawk mortality has some sort of increased threshold of acceptability in your mind?
Could you explain what you meant please?

Colin
 
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