The Germansweek wind farm proposal is for 6 turbines with an installed capacity up to 9 megawatts (MW) of renewable electricity. With a capacity of this size in such a windy part of Devon, the project will meet the average needs of some 5480 households. This wind farm would also help offset the annual release of over 11,000 tonnes of carbon dioxide, the main greenhouse gas contributing to climate change, which would otherwise come from power stations burning fossil fuels. Furthermore, the Germansweek wind farm is expected to create 30 full time jobs and a further 6 support roles, with more than 100 jobs created during construction. The area within the site boundary is approximately 295ha of which approximately 0.85 ha will be used for the proposed wind farm. Minimal habitat will be lost as a consequence of the construction of the wind farm.
Recently, the UK Government has placed a 'Renewables Obligation' on all UK electricity suppliers to provide 12.5% of their electricity from renewable sources by 2010 and 15% by 2015 (Sustainable Development Commission, 2005). The generation of wind power continues at an outstanding level throughout the world. Worldwide, wind energy reached over 175,000 MW of installed capacity as of June 2010 and 1,900,000 MW of global capacity by 2020 was predicted based on accelerated development and further improved policies (World Wind Energy Association, 2010). In fact, wind energy continues to experience world growth rates of 20% per annum. It is now Government policy that 20% of the UK's primary energy will be generated by renewable energy by 2020 in line with European Union targets for the reduction of greenhouse gas emissions (GHG).
The proposed development site is located approximately 8.5 mile north east of Launceston, County Devon. Germansweek has an abundant wind resource with some of the highest average wind speeds of 6.9m/s. It is important that this resource continues to be harnessed for renewable energy adding to the development and capacity of the Southern UK wind industry. A wind farm will also help contribute to the regional economic growth of communities, while reducing the reliance and security of fossil fuels.
The population of the area is low density and dispersed, as is typical in rural farming areas. There is a number of working farming properties and associated residences in the vicinity of the proposed wind farm site.
Figure 1 The Germansweek wind farm proposalC:\Users\Tegratesla\Desktop\1.png
The proposal of Germansweek wind farm:
Six wind turbines
9MW of total power output
11628 tonne of CO2 emissions can be saved annually
£ 35,496,000 of generating costs per kWh of electricity for the project
Creation and safeguarding of jobs, e.g. manufacturing of wind turbines, construction, operation, maintenance and removal of turbines, research and monitoring
The operational wind farm will include the following key components:
Six reinforced concrete foundations
Crane hard-standing areas adjacent to each wind turbine
2km of 4m width permanent access roads from the site entrance to the turbines and ancillary development
Underground electrical and cabling linking each wind turbine with the site control building
A control building comprising of a control room, switch room, metering room, auxiliary transformer and welfare facilities
Ecology and nature conservation
Wind-farms might affect birds by increasing mortality rates through collisions, by disturbance of birds in their resting and feeding habitat, or by altering the amount of resting and feeding habitat. Large wind- farms may also produce a barrier effect, deflecting bird movements away from their intended tracks. The potential impacts can be divided into two subjects of expected impact, namely disturbance and collision risk.
Birds are likely to be displaced from foraging habitat by the disturbance caused by wind-farms in operation, in effect a loss of feeding habitat. They may become habituated to such disturbance over time, and it is even possible in some cases that once such habituation occurs, some species might benefit from increased amounts, or concentrations, of food in the vicinity of individual turbines or wind-farms. Thus short term and medium term effects of wind-farm development might differ, or effects may differ between species. Particularly sensitive bird species might never habituate to wind-farms and be permanently displaced from the area or continually disturbed from these areas.
There is the risk that birds will collide with the wind turbines in operation. This can affect wintering and staging migratory birds, which over-fly the wind-farm area every day over longer periods. Furthermore, it can affect a population of migrating birds, where a smaller or larger number of individuals over-fly the wind farm area once or twice a year. Besides, the illumination by navigational lights can attract the birds and subsequent increase in the risk of collision.
Bats are at risk from wind turbines, researchers have found, because the rotating blades produce a change in air pressure that can kill the mammals. Canadian scientists examined bats found dead at a wind farm, and concluded that most had internal injuries consistent with sudden loss of air pressure. Bats use echo-location to avoid hitting the blades but cannot detect the sharp pressure changes around the turbine. The scientists say wind farms are more of an issue for bats than for birds.
Noise comes from different sources during the construction, the operation and the removal phase. During construction, noise will be emitted, for instance, from transporting, pile driving, preparation for foundations, laying of cables. The noise generated by these sources, except mono-pile driving, will primarily be of low frequencies. If mono-piles are used as foundations for the turbines, pile driving will be used to construct them and this is likely to cause high noise levels.
The hydrology of the site is not considered to be adversely impacted by the proposed development. The effects on the hydrology are expected during the construction phase of the development. Minimal effects on the hydrology are expected during the operational phase of the development with a slight increase in impermeable areas contributing to surface runoff. The main potential impacts are during the construction phase, which can be controlled by adopting standard mitigation measures (EPD, 2006).
Greenhouse gas emission
Wind power avoids many of the environmental costs of conventional electricity generation, including reduction in air quality and the damage to the natural environment caused by acid rain from pollutants such as oxides of nitrogen (NOX) and sulphur dioxide (SOX). Electricity produced from renewable sources can displace electricity that would otherwise be generated from conventional fossil fuel power stations and reduces emissions. For each year of its operation, the wind farm would also directly prevent the emission of carbon dioxide (CO2). As such, the development would contribute both to improved air quality at a local and regional level and would also contribute towards achieving national targets to reduce carbon dioxide.
Landscape and visual
The physical effects on the landscape are the direct effects from the proposed wind farm on the site, which can alter the land cover, landscape features and the landscape character of the site. In addition, the operational activities associated with the proposal, including the movement of vehicles within the construction, operation and decommissioning phases, can extend the direct physical effects beyond the immediate site area.
The assessment of visual effects has been made through the Geographic Information System (GIS) analysis of agreed viewpoints, selected to represent the range of views and viewer types from where the proposed wind farm is theoretically visible and to determine whether the effects are likely to be significant.
Most of the problems of traffic will occur during the building phase. Dozens of truck movements will be needed to supply heavy machinery, road metal, concrete and building materials. The blades and towers are of extreme length up to 45 m and take some time to navigate the roads. Traffic delays would be expected at some times and should be tailored to local traffic requirements. Damage to the roads can be expected and should be remedied by the operator. Dust and noise from the road traffic may also be a problem. Local roads are sometime improved by the operator by removing difficult curves, road widening and improving the road surface to enable heavy truck movements to use the roads without disruption.
Due to the earth excavation and road works there will be a range of erosion problems if the area experiences serious rainfall. Dust from exposed cuttings may also be problematic. This may result in a problem downhill with landslips or streams carrying additional silt and its resulting flooding consequences.
The blades can create flicker in two ways. Sunlight reflecting off the blades will occur at certain angles of the sun and windmill. This can create a strobe effect in affected areas which can be some distance away. With the sun behind them, the turning blades can cast moving shadows across nearby houses and landscape. Although generally affecting residences nearby, the strobe effect can be difficult to block out.
There is anecdotal evidence that wind farms attract tourists. In addition, the construction and maintenance of access roadways for the turbines would undoubtedly attract residents and tourists who enjoy activities such as hiking, camping, birding, and snowmobiling.
Visual impactC:\Users\Tegratesla\Desktop\building-wy change.jpg
Figure 2 Viewshed of wind farm with 7km radius
Viewpoint is chosen from within a 7km radius from the wind farm. These are carefully chosen to provide a representative sample of views towards the wind farm site in a 360O radius.
Country house site
Any field drainage encountered and disturbed during construction will be repaired prior to reinstatement. During construction of the turbine foundations, temporary drainage and silt traps will be installed. In the event that a storm drainage system is required, a Sustainable Drainage System (SuDs) should be incorporated into the scheme.
Spill kits should be stored on site containing absorbents and booms to address any fuel spillages as a result of refuelling vehicles. The storage of fuel on site should be restricted any requirement to store fuel should be within appropriate containment facilities.
Any concrete required is likely to be mixed off site, in the unlikely event there is a requirement for onsite mixing this should be carried out within containment to prevent release into the environment.
All contractors should be trained in the handling of hazardous substances, pollution prevention and in the use of pollution prevention equipment. All construction works will be undertaken with reference to relevant Pollution Prevention Guidelines (PPG).
Noise restrictions need to be set into the consent process to protect local residents from problematic noise. Typical ambient noise will need to be measured before project construction begins. If possible, noise should be limited to agreed limits and if outside that level, turbines either automatically de-rated or shutdown. Typically complaints would be handled by the local governing body, but residents may be able have agreement to raise the problem directly with the operator. Low frequency and particular tonal noise has been identified and may be problematic at levels lower than prescribed noise limits. Also, restrictions of operating times may need to be set into the consent decision limiting night work which could disturb neighbours.
References and Appendix
Barrios, L. and Rodriguez, A. (2004). Behavioural and environmental correlates of soaring-bird mortality at on-shore wind turbines. Journal of Applied Ecology 41: 72-81.
Barrios, L. and Rodriguez, A. (2007). Spatiotemporal patterns of bird mortality at two wind farms of Southern Spain. In: De Lucas, M., Janss, G.F.E. and Ferrer, M. (Eds.), Birds and Wind Farms. Quercus, Madrid, Spain, pp. 56-72.
Iglesias, G., Castellanos, P. and Seijas, A. (2010). Measurement of productive efficiency with frontier methods: A case study for wind farms. Energy Economics 32 (5): 1199-1208.
Dirksen, S., Spaans, A.L., Van der Winden, J. (1998). Nocturnal collision risk with wind turbines in tidal and semi-offshore areas. In Ratto, C.F., Solari, G. (Eds) Wind Energy and Landscape. Balkema, Rotterdam, pp 99-108.
Environmental Protection Department (2009). Environmental Considerations and Mitigation Measures for Sewage Pumping Station. [Online] Available at: http://www.epd.gov.hk/epd/english/environmentinhk/eia_planning/guide_ref/egn_6.html [Accessed 2 December, 2010]
Leddy, K.L., Higgins, K.F. and Naugle, D.E. (1999). Effects of wind turbines on upland nesting birds in conservation reserve program grasslands. Wilson Bulletin 111: 100-104.
Richard B. (2008). Wind farms put pressure on bats. Environment correspondent, BBC News website. [Online] Available at: http://news.bbc.co.uk/1/hi/sci/tech/7581990.stm [Accessed 28 November, 2010]
RSPB (2004). Climate change and birds. RSPB information sheet. [Online] Available at: http://www.rspb.org.uk/Images/Climate%20change%20and%20birds_tcm5-56407.pdf [Accessed 28 November, 2010]
Sustainable Development Commission (2005). Wind Power in the UK. [Online] Available at: http://www.sd-commission.org.uk/publications/downloads/Wind_Energy-NovRev2005.pdf [Accessed 3 December, 2010]
Thelander, C., Smallwood, K, Rugge, L. (2003). Bird Risk Behaviours and Fatalities at the Altamont Pass Wind Resource Area. [Online] Available at: http://www.nrel.gov/docs/fy04osti/33829.pdf [Accessed 2 December, 2010]
World Wind Energy Association (2010). Gigawatt added in First Half of 2010. [Online] Available at: http://www.wwindea.org/home/index.php?option=com_content&task=view&id=281&Itemid=43 [Accessed 2 December, 2010]
World Wind Energy Association (2009). World Wind Energy Report. [Online] Available at: http://www.wwindea.org/home/images/stories/worldwindenergyreport2009_s.pdf [Accessed 2 December, 2010]
A performance profile for Germansweek wind farm