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Bardwell mill and a planning application

Bardwell mill and a planning application by Victor Reijs is licensed under CC BY-NC-SA 4.0

An application for housing estate

Evaluation application

• page 5: important to read "adversely affected".
  In American law this means:
  Environmental & Property Law: An action that causes identifiable harm or unreasonably interferes with the use, enjoyment, or structural soundness of a property or natural resource.
  What is the meaning in UK law?
• Section 5: the interpretation of the plan looks to be correct, when I read the proposal files myself.
• Section 6: for now I assumed the data and calculations of Bardwell Mill are correct. They incorporated the change of z0 (roughness length).
• Section 7: Nageli measured two configuration of fences: one called 'dichten Schilfwand' and the other 'lockeren Schilfwand' (Bild 2, 1953):
  
  'Dicht Schilfwand' is thus not 'Solid' it has an optical porosity of 15 - 20%!
  This porosity of will change the calculated wind behavoir behind the object.
• Section 9 (as mentioned in the text): I think that comparig things should be done during daylight/working hours (or between 09:00 and 17:00) so not for 24h per day. The wind during night time is normally lower (diurnal variation of the wind). This will have impact on the (effective) milling hours.
  Here are windrose examples of a MET (KNMI-Cabauw) readings of a station in an open environment (z0 ~ 0.05m) for 8h working day or a 24h day:
  
• Please check first the influence of this 'Dichte Schilfwand' issue and the daylight/working hours.
• Section 10. So the question is, is an average 5% reduction in speed (averaged over the whle windrose: which is 14% in energy) an 'adversely affected" phenomenon? I would say yes, more than 10% energy is a lot.
  
• Section 10: I have not been able to find data about the trees that will be planted as part of the development.
  It is essential to know the green planning in this development.
  A tree (in fully leaved status and mature hieght) should be evaluated as an obstacle (as solid or as poreus [say with an optical porosity of 20%).
• The Dutch molenbiotoop method of The Hollansche Molen (https://www.molens.nl/sites/www.molens.nl/files/documenten/20220715_MEM_Biotoop%20Dossier%20Biotoopformule.pdf and https://www.archaeocosmology.org/eng/DHMformula.htm ) says that nothing should be heigher than de lowest position of sail tip within a cicrle of diameter of 100m.
  This is mainly not because speed reduction, but due to higher turbulence behind obstacles. As the development is certainly 100m to close the mill; this turbulence would badly effect the effectivecy of the mill and it will give larger stesses on the wings (and can cause over time metal fatigue).
• Here are the numbers when using the Dutch molenbiotoop method (cross section plan of the devlopement is here):
  
  EffH_dhm is maximum height (m) of a obstacle at that present development distance. x_dhm is the distance (m) that the obstacle with a height in the development should be placed.
  And all x_dhm are for all proposed houses too large; so the proposed houses should all be lower and/or more distant!!!
• A CFD of the development migth be important, as it is a relatively large development.
  How to conduct a CFD for a traditional windmill biotope can be seen here.

Quantification of speed reduction

Conclusions

• Please check first the influence of this 'Dichte Schilfwand' issue, the daylight/working hours and green planning.
• It is essential to know the green planning in this development.
• There is a 13% reduction in speed in the North-West region due to this proposed developent: which is 33% in energy. So an 'adversely affected" phenomenon.
  
• All max-house-heights (x_dhm) are too large; so the proposed houses should all be lower and/or more distant!!!
• A CFD of the development migth be important, as it is a relatively large development.
  

Acknowledgements

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