Markieta, Michael; and Carver, Steve
Regular visitors to the Scottish hills cannot have failed to notice the increasing environmental influence of renewable energy in recent years. Windfarms now feature prominently in views from many of our most iconic ‘wild’ mountains, a trend likely to accelerate with the Scottish Government’s tight timetable to generate all of Scotland’s power needs with low carbon technologies. If many more large onshore windfarms now look inevitable, then the question of how best to minimise their environmental impact arguably gains greater urgency. Is it possible both to develop and to conserve the large areas of scenic wild landscape for which Scotland is notable in a European context? Where are the areas which if developed would minimise the extent of intrusion on the remaining uninfluenced landscape? A new study by Steve Carver and Michael Markieta of the Wildland Research Institute  at the University of Leeds aims to address this question.
The team summarise their work for UK Hillwalking  here, with links to the interactive mapping they’ve been using to determine landscape impacts.
We’ve all seen the headlines. We’ve all seen them sprouting up across the mountain landscape, cluttering the horizon as we look out from our favourite hill. We’ve all had those well-worn debates with friends and colleagues across the dinner table or down the pub over a pint as to why they are a good or a bad thing. We all know we have to do something about our insatiable demand for electrical energy, but what we don’t know is just how much impact wind turbines have and will have on our landscape. What we do know is that wind energy is having a significant impact on the Scottish landscape and that this is set to increase over the next few years as more wind farms are constructed. The SNP are firmly committed to increasing investment in the renewable energy sector and have set a target for Scotland to generate 100% of its energy requirements from renewable sources by 2020. Although the renewable mix is likely to include hydro, wave and tidal power it is likely that the bulk of the burden in reaching this ambitious target will fall on the shoulders of wind, both onshore and offshore, because this is where the engineering challenges are better understood and the investment:returns ratio is most profitable. This can only mean one thing… more turbines on the hills and along our coasts.
‘The area of the Scottish countryside that is free from visual influence caused by built development declined from 41% in 2002 to 28% in 2009’
A recent analysis carried out by Scottish Natural Heritage  (SNH) showed that the area of the Scottish countryside that is free from visual influence caused by built development declined from 41% in 2002 to 31% in 2008. More recently still, this figure has now declined to 28% in 2009. While this figure is based on all built structures (airports, roads, railways, pylons, urban areas, etc. and importantly existing wind turbines) it is an alarming trend and one that potentially masks the contribution to this erosion of landscape character and values that is due to wind energy developments. Earlier work by SNH showed that in the central Highlands the amount of land free from impacts caused by road and rail access, plantation forestry, hydro power and electrical transmission lines declined rapidly between 1860, 1950 and 2000. Government claims that “Scotland has the potential to become the Saudi Arabia of renewable” backed by the 100% renewable target has surely given a green light to further expansion of wind energy over the next few years. Such a trend is not without its detractors and questions have been raised in Parliament by the John Muir Trust  on this.
Meanwhile, other aspects of the Scottish economy depend heavy on tourism with estimates ranging from £5-10billion from 15million visitors per year with figures set to increase by almost two fold by 2020. Of course, some of this revenue is from people visiting cultural centres like Glasgow and Edinburgh, but many of Scotland’s visitors come for the landscape whether it’s to walk, climb, sail, play golf, fish, shoot or just enjoy the magnificent countryside from bus or car. A key characteristic of the Scottish countryside is its wildness; the qualities of which are most strongly expressed in those areas that are dominated by natural or near-natural vegetation, lack of human intrusion from built structures and the rugged, challenging and remote nature of the land. Recent surveys on behalf of SNH in 2007 and 2010, respectively, have reported that 91% of Scottish residents think that it is important to have wild places and 98% thought that wild land in Scotland should be protected.
‘Where are the areas which if developed would minimise the extent of intrusion on the remaining uninfluenced landscape?’
It would seem that 2020 is a significant date here in both respects; as an ambitious target for renewable energy generation and a hopeful one for tourism revenue. However, there seems to be an obvious conflict, one that implies that more wind turbines will mean a bigger impact on the landscape and potentially, therefore, less tourism. Research currently underway at the Wildland Research Institute at the University of Leeds is attempting to provide some of the answers as to exactly how existing and planned wind farms are impacting on Scotland’s landscape. The work attempts to provide greater information about the cumulative effects of wind turbines in the Scottish landscape, such as how many turbines are visible, how much of them can be seen given the terrain and exactly big they look . As already discussed, the extent of Scotland’s landscape that is unaffected with a view of modern human artefacts is decreasing rapidly and the effect of wind turbines needs to be accurately monitored. Our analysis takes into account all turbines in the various stages, including those already built as well as those in approved, planned and scoping stages. The basic aim of this study is to identify areas where further development of Scotland’s wind energy potential will not mean further erosion of the landscape quality and further reduction of the 28% figure.
See Figure 2 as an interactive map on Maptube here. 
To do this we make extensive use of computer mapping techniques and digital map data together with a technique known as “viewshed” analysis to map the turbines’ zone of visual influence (ZVI). Generally, a viewshed analysis is performed to identify the areas from where a turbine can be seen or not seen. The results show the areas that are within or outwith the ZVI as a map like the one shown in Figure 1. With modern computing techniques, a viewshed for over 4200 wind turbines in Scotland can be computed in a matter of hours, rather than days or weeks or even months. Currently, 71% of Scottish countryside is without a view of an installed turbine. However, if all the wind turbines that are currently approved or in the planning or scoping phase are built, then this figure will fall to 49%. Added to the existing visual impact from other human artefacts reported in the SNH work, then it is unlikely that many areas of the Scottish landscape will be free from visual influence by the 2020 date. However, logic dictates that there must be some places where a wind farm could effectively be hidden from view, so that those areas currently without a view of a turbine or other human artefact are either not adversely affected or reduced further still. By utilizing careful application of the viewshed analysis, we can reverse engineer the primary outputs (where you can and can’t see a wind turbine) to check if there are any areas which can be further developed so as to not further reduce the amount of the remaining uninfluenced landscape.
Early indications are that there are very few areas that can be further developed without reducing the remaining uninfluenced landscape. This begs a further question: where are the areas which if developed would minimise the extent of intrusion on the remaining uninfluenced landscape? Inherently, the question is rooted in humanistic perception of acceptable levels of cumulative impacts. For discussion’s sake, the top 10% lowest impact zones are shown above (Figure 2). These are located mainly around existing wind farms, such as Whitelee Wind Farm, as well as various offshore areas.
Figure 3 interactive version here. 
Figure 4 interactive version here. 
We have also run a similar analysis for areas in Scotland that are protected for their exceptional biodiversity or landscape value. The total land area protected for its biodiversity (including Natura2000 sites, National Nature Reserves, etc.) is actually very large and consequently the analysis reports that there are very few areas (Figure 3) that do not have a view of these protected areas. However, fewer areas of Scotland are covered by landscape designations (National Parks and National Scenic Areas) and therefore the viewshed analysis reveals much larger regions (Figure 4), mainly in Aberdeenshire, which do not have a view of a protected landscape.
‘Further renewable energy developments in Scotland need to be carefully sited to avoid conflict with landscape policy and tourism potential’
While the results for the biodiversity and landscape areas are different, there is an important point to be made here, namely that the biodiversity areas are often quite fragmented whereas the landscape areas are not. Biodiversity can be found across a range of scales from your local pond to whole landscapes, but in the long run the resilience and sustainability of that diversity depends on the connectivity and unfettered state of natural ecosystems and processes, and that these require large areas to be natural in. So, in the long run it is actually quite difficult to separate biodiversity from landscape as logic dictates that high biodiversity tends to produce beautiful and natural looking landscapes, while large, unmodified landscapes gives nature room to flourish, such that the two remain mutually inclusive. The important take home message here is that policy and decision making on wind energy in Scotland needs to take into account the cumulative impacts of not only the wind turbines on the Scottish landscape, but also the protected areas for their exceptional biodiversity or landscape characteristics and values. The problem here is that while the area within protected high value landscapes is remarkably beautiful, the viewshed from within and into the protected landscape area extends way beyond the boundary. In essence, the value of the National Park or NSA is detracted by any tall wind turbines outside of boundary that are visible, but also within the viewshed of the protected area. Results suggest that 58% of the installed wind turbines are visible from a designated protected landscape and if wind turbines in all stages of development are taken into consideration, this figure may well increase to something like 62%.
Interactive map of Wildness Quality here. 
It is our opinion that further renewable energy developments in Scotland need to be carefully sited to avoid conflict with landscape policy and tourism potential. There is no perfect solution, so we will probably have to accept some level of compromise both from a landscape and biodiversity perspective. While what we are doing here attempts to provide a technical response to a complex social (landscape values and climate change) and economic (energy vs tourism) problem, it is clear that the answer is essentially a spatial one and the kind of methods described can provide the information base on which better informed decisions and policy can be made.
Michael Markieta and Steve Carver
Wildland Research Institute , University of Leeds
URL to article: https://www.wind-watch.org/documents/damage-limitation/
URLs in this post:
 Wildland Research Institute: http://www.wildlandresearch.org
 UK Hillwalking: http://www.ukhillwalking.com/news/item.php?id=62670
 Image: https://docs.wind-watch.org/Braeriach.jpg
 Scottish Natural Heritage: http://www.snh.gov.uk
 John Muir Trust: http://www.jmt.org
 Image: https://docs.wind-watch.org/viewshed-analysis.jpg
 Image: https://docs.wind-watch.org/lowest-impact-zones.jpg
 See Figure 2 as an interactive map on Maptube here.: http://maptube.org/map.aspx?s=DGxXpxEjHLSiRCSMEJPApcHAp1bAoTjd
 Image: https://docs.wind-watch.org/viewshed-analysis-biodiversity.jpg
 Image: https://docs.wind-watch.org/viewshed-analysis-landscape.jpg
 Figure 3 interactive version here.: http://maptube.org/map.aspx?s=DGxXpod4y0qVZyXBCSwKXBwKdWwKE4
 Figure 4 interactive version here.: http://maptube.org/map.aspx?s=DGxXppEky0qWBJfBCJwKXBwKdWwKE4
 Interactive map of Wildness Quality here.: http://maptube.org/map.aspx?s=DGxXppVkHLSnMJmcEJDApcHAp1bAoTjd