oOn 15th November Teignbridge District Council launched the third part of its consultation on the Local Plan. This third part of the consultation covers Renewable Energy, Gypsy and Travellers and Residential Sites Options. The consultation closes on 24th January 2022. The renewable energy part of the consultation covers site options for wind energy as well as policies in respect of wind and solar energy.
ACT plans to respond to the sites and policies for wind and solar energy. We encourage you to do this direct to TDC. We also welcome your views and comments, so we have included a facility for you to do this.
We believe that renewables are an essential part of the overall effort to remain below the climate tipping point, caused by temperature rise of more than 1.5oC. For more information on Climate Change please refer to Why this is an Emergency. To read about actions needed, please see our Energy & Built Environment webpage.
When responding to the TDC online consultation, each wind site has a number of criteria against which free text can be entered. You can also comment on policies associated with the potential solar areas identified for Teignbridge.
To help you see all the information provided by the consultation, as well as other related information, we have extended our Local Plan mapping data web page to cover proposed wind sites. Please read the instructions first to learn about how to use this data and how to enter comments you’d like to share with ACT against each site.
Although solar PV, especially with Li Ion battery storage has its part to play, this is mainly for smaller behind-the-meter applications. Ideally rooftops or ground mounted close to buildings. The following headings therefore represent our current views on the Part 3 consultation for wind. We welcome your input on this.
Why we need local wind
In order to stand any chance of restricting global temperature rise to 1.5˚C above pre-industrial levels everyone needs to cut their greenhouse gas emissions as fast as possible. According to Our World in Data 73.2% of global greenhouse gas emissions are attributable to burning fossil fuels to generate energy. To rapidly reduce emissions from energy production we all need to:
- Reduce energy consumption, i.e. cut out waste and reduce non-essential consumption.
- Increase the efficiency of the devices/processes that use this energy, e.g. A rated or higher.
- Electrify transport, heating and industrial processes as these are the main consumers of fossil fuels. Electrification is currently the most effective way to decarbonise energy as renewables become more widely deployed.
Electrification of transport and heat will increase electricity demand, if sufficient low carbon generation isn’t added, this could cause the Carbon Intensity of grid electricity to increase, the opposite of what is needed. This is because more gas will be used to supply the additional energy needed.
The first wind farm in the UK was opened at Delabole in Cornwall in 1991. Between 2009 and 2020 wind energy in the UK grew by 715% , but most of that generation is on-shore in Scotland and off-shore, mainly the east coast of England. These are a long way from Teignbridge involving electricity transmission losses.
On-shore wind is a mature technology, which is also currently the cheapest source of electricity and has one of the lowest Carbon Intensities. It is needed as part of the energy mix and can be deployed now.
Teignbridge currently has negligible wind generation, but has significant solar generation in the sunnier summer months. In winter, just as energy is needed for electrified heating (e.g. heat pumps), the local Carbon Intensity of the electricity supply is at its highest. If supply and demand were better matched for more of the time, Teignbridge’s Carbon Footprint would be reduced. Wind generation is highest during the colder months.
How much of Teignbridge’s demand could be generated
The consultation estimates that an additional 10,000 homes would require 66GWh of electricity per year, so each home is estimated to consume 6.6MWh of electricity per year. If this level of consumption were repeated across all homes in Teignbridge after full electrification of heating and transport, then annual demand would be in the region of 462GWh.
The University of Exeter has estimated the generation from the sites identified in the consultation would be 217GWh using a mix of 1MW and 2MW wind turbines, this would be 47% of Teignbridge’s estimated electricity demand.
Wind turbines are designed for an IEC wind class from I for the strongest winds through to IV for the lowest wind speeds. The site with the strongest winds in Teignbridge has class II winds, most are III or IV. Turbines designed for class I winds have much smaller rotors and towers than those designed for class IV for the same power rating.
We believe that it would be more effective to place higher rated turbines at sites with the strongest wind classification. This is not only more cost effective but also minimizes some of the potential adverse impacts of having wind turbines in Teignbridge. We believe such an approach would probably meet or exceed all of Teignbridge’s estimated electricity demand.
We have placed turbines in line with the consultation to illustrate their potential impacts. Using Local Plan mapping data web page, you can see the example turbines placed to comply with various restrictions. Two example scenarios can be selected, those specified by the consultation (default scenario) and fewer higher rated turbines. We have done this to illustrate the reduced noise impact of these higher rated turbines.
Proximity to Housing- Noise from wind turbines
Modern wind turbines are remarkably quiet compared to a decade or more ago. We have provided visual outlines where the sound power from the turbines is just lower than 45dBA, 40dBA and 35dBA. The noise level inside a quiet library is 35dBA, 40dBA is the level in a quiet rural area when the wind is not blowing. When placing turbines on the maps, the default noise level at neighbouring properties is set to be less than 40dBA.
Many of the proposed sites have a relatively high ambient noise level, often from road traffic and proximity to built up areas. While an ambient day time noise level in some location may well be 35dBA or less, this is quite unusual in the vicinity of the proposed sites and would need to be considered if and when these sites are developed.
Noise from wind turbines is site and wind speed/direction dependant, so the mapping circles we have provided are only indicative. More detailed and specific measurements will be made as part of any and every turbine application, so the local community will have the ability to comment.
The UK comprehensive guidelines for Assessment & Rating of Noise from Wind Farms quotes the following from the WHO:
“Few people are seriously annoyed during the daytime at noise levels below around 55dB(A)Leq outdoors. Noise levels during the evening and night should be 5 to 10dB lower than during the day”
Ecological and Land Use Impacts
The main ecological concern of wind turbines relates to bats and birds. For both bats and birds there are mitigation solutions, which suggests that a strategy of monitoring and mitigation is likely to be effective.
Apart from the relatively small loss of land needed to support a wind turbine and gain maintenance access, there are no other significant impacts to land use or its ecological value.
Bats
Exeter University undertook research on the interaction between bats and wind turbines for DEFRA by monitoring a number of wind sites, a range of wind conditions and recording bat fatalities. More accessible references, are:
- https://www.nature.scot/doc/bats-and-onshore-wind-turbines-survey-assessment-and-mitigation
- https://www.bats.org.uk/news/2016/09/bats-and-wind-turbines-research-project
- https://www.exeter.ac.uk/news/research/title_551128_en.html
- https://www.nature.com/articles/s41598-021-82014-9
It seems that some relatively simple mitigation measures can allow wind turbines to generate most of the time:
- Turbines only turned off when there is a high risk to bats (example low wind, summer evenings), turbines can now have this automated.
- Ongoing monitoring to refine the circumstances when turning off needs to occur.
- Absence of bats at the pre-construction stage is not a good indicator of their absence during turbine operation. Subsequent mitigation is more likely to be effective than pre-construction surveys.
- There are devices that emit an ultrasonic signal, which effectively blocks the bat’s radar, so they do not approach the turbine. This is mounted on the turbine
Birds
Several references suggest there are much higher numbers of bird deaths in general from cats, collision with windows and traffic compared to deaths from wind turbines.
This reference discusses both bats and birds. It suggests that large birds are more at risk than smaller ones. It reports Norwegian research where turbines with one blade painted in a contrasting colour has dramatically reduced fatalities.
Infrastructure and Highways Impacts
These include site access during construction, especially for larger turbines. The consultation states that these will be considered on a case by case.
Connection to the electricity network is a key factor. There does not appear to be much consideration for this in terms of site selection. We have included mapping information on current electricity distribution/transmission lines and sub-station.
The distribution network operator Western Power Distribution (WPD) has been made aware of these potential sites. This information should allow them to better consider strategic network reinforcement, something they are not currently required to do by the regulator Ofgem.
Landscape and Heritage Impacts
Undoubtedly most wind turbines will have a visual impact. Like electricity pylons, roads and housing developments, they are manmade structures in the natural environment. The question we need to answer is what the balance is between the benefits and the detriments.
To minimise their visual impact, wind turbines are painted white or grey to blend into the sky when viewed from the ground. The lower part of the mast can be painted to allow this to blend into the surrounding’s natural structures. For safety reasons wind turbines need to be visible from overhead low flying aircraft.
We are more likely to accept new structures that are familiar to us, like roads and housing. This despite them having a greater detrimental visual, ecological and of course greenhouse gas emission impact compared to wind turbines. Road and housing are also more likely to persist for a lot longer than wind turbines, if eventually we are able to generate our energy from other low Carbon technologies. We could also limit wind turbine deployment if we become more careful about how much energy we consume and distribute energy better.
Other Notes
This space is made available in the on-line consultation for making comments on the benefit and impact of wind turbines not covered above.
We believe that if we are to avoid the existential threats resulting from Climate Change, on-shore wind turbines will be necessary. They are by far the most effective renewable technology available to us now. Nothing comes without a degree of negative impact, we need to minimise the impact of wind turbines. The consultation materials list many of these safeguards, you can also read general references to these on the internet, e.g. for on-shore wind.
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