AESTHETIC IMPACT FROM WIND PARKS Dr Theocharis Tsoutsos, Assistant Professor Zacharias Gouskos, Stefanos Karterakis, Elpida Peroulaki ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

In the most islands the development of WPs was gradual Most of the negative opinions due to: the noise the aesthetic impacts ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

LANDSCAPE & WIND PARK DESIGN ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

1. Α: Avoid homogeneously structured spatial backgrounds Β: Prefer texture zones 2. Α: Αvoid skyline & distinctive lines Β: Prefer below the horizon 3. Α: Αvoid less structured areas Β: Prefer rich built structures 4. Α: Avoid annoyance outside the defined zones Β: Adjust within the existing zones ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

WIND PARK SITING  In straight line or curved Rows along terrain features (ridges, coast-lines, etc) - In parallel lines Same distance between WTs in different rows Distance between the rows larger than distance between WTs ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

In small clusters In simple geometric shapes/patterns, e.g. as 3 WTs in a row or in equilateral triangle “Randomised” siting No rows or shapes ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

VISUAL AND TECHNICAL DESIGN OF THE WIND PARK ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

WT TOWER Tower operation: elevation of the WT above the ground The designers put the tower last in the design priority ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

THE NACELLE COVER The cover: - hides the mechanical parts from view - protects the maintainers - reduces the noise level ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

NUMBER OF BLADES 2-bladed WTs seem to produce annoying unusual visual effects 3-bladed WTs give the impression of visual balance ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE The absence of symmetry is more intense when the blades are motionless

CONTRUCTION MATERIALS AND COLOUR Color and material can contribute in the invisibility of WTs The appropriate color is selected according to the area Often is suggested the use of neutral wrap to minimize the reflection ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

ORDER The visibility zone in a distance about 10 times the turbines height; although visible the WTs, may not be intrusive The way we view WTs in the landscape, close or not, strongly reflects the need for order; many of the negative commends on the aesthetic of WTs are expressed as disorder in the landscape ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

MOTION The motion extends the visual zone influenced by WTs. In 2,5 km, it is the motion rather than the size of the WT that draws the eye. The motion can highlight the WT in distances ≥8 km. The motion communicates “usefulness”, because WTs operate doing their job. The inoperative WTs are, often, considered as source of visual annoyance. ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

VISUAL DENSITY AND UNIFORMITY Visual uniformity: the visual impression of a “uniform whole” created by a cluster of WTs with the same design characteristics (tower, nacelle, blades). Significant parameter of uniformity: WT rows to have uniform density and the WTs of a row to be in the same distance. ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

AUXILIARY INSTALLATIONS Should: 1.Be constructed with natural indigenous materials to be harmonized with the landscape 2.Site them below the horizon line (e.g. off the horizon line on a ridge). ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

FENCING, ROADS, LIGHTING Unnecessary fencing of the WPs isolates them giving a threatening & hostile character Visual impact can be also caused from flashing lights particularly annoying during the night Usually the most annoying piece (except of the WP itself) are the access roads ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

AESTHETIC DIRECTIVES ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE 1. Visual uniformity 2. Avoid fencing 3. Minimize or avoid roads 4. Underground transmission grids 5. Limit auxiliary installations 6. Remove of non operating WTs 7. Avoid bluffs 8. Control of ground erosion and protection of the local flora 9. Remove of useless objects 10. Periodic cleaning

METHODS TO ESTIMATE THE VISUAL IMPACT OF WPs ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

Spanish method Contains: 3D analysis of the WP and the surround area in order to get simulated pictures application of estimation of visual annoyance in neighboring settlements  ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

Visibility coefficient from the village (α) Division of the village in parts n : parts of the village with different views of the WP X i : number of WTs visible in the area WM: total number of WTs  Visibility coefficient of the village from the WP (b) It counts the number of the visible houses from each WT ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

 Visibility coefficient of the WP if this will be considered as oblong (c) C = ν. n ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

sideParameter ν front1,00 diagonal0,50 along0,20 Number of WTs Parameter n 1-30, , , ,05 >301,10 Distance coefficient between the park and the village(d) Distance xCoefficient d x<500m1,00 500<x<6000m1,05-0,0002. x 6000m<x (if the park is visible) 0,10 ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

Population coefficient of the village (e) Inhabitan ts Coefficient e >3001, , , , , ,20 00,00 Partial assessment (PA) PA = a. b. c. d. e Partial assessment Effect 0,00-0,10minimum 0,10-0,30low 0,30-0,50medium 0,50-0,70significant 0,70-0,90Very significant 0,90-1,00high ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

Total assessment Population coefficient of those people who permanently affected by the view of the WP vs the total population of the area. C: total coefficient of population’s influence ΝΗ m : population of the village m ΝΤΗΕ: total population of the area ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

METHODOLOGY FOR THE DEFINITION OF THE VISUAL LIMITS (Shang & Bishop) Three parameters: 1. Relevant size of the WT 2. Visual contrast of the WT 3. Atmospheric dispersion It uses the following tools: GIS Image processing software (e.g. Adobe Photoshop, POV- Ray etc) Linear deterministic models Internet ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

DEFINITION OF THE RELEVANT SIZE OF THE WT This method refers to “size” as an observer can understand by comparing it with another with similar size. Steps: 1. Construction of a simplified model of WT in the software POV- Ray (tower height 50 m, diameter 1-2 m, ρότορας with 3 blades 26 m each) 2. Rotation of the blades for 15 images in black background by using POV-Ray. ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

3. Copy of the 15 designed WTs in the real picture of the area by using Adobe Photoshop 4. Combination of 15 simulated photos, in order to present the rotation of the blades in a GIF file, which simulated the motion ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE DEFINITION OF THE RELEVANT SIZE OF THE WT

Τhe results of the poll converge in an average size 4.02 (= 153 pixels) 20% larger than the size of the static WT (=130 pixels). Based on the image scale is estimated the ratio pixels:m 2 so is estimated the relevant size of the WT in m 2 (parameter Μ). Τhe size is defined by: S=Μ*(arctan(1/d)*60) 2 ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE DEFINITION OF THE RELEVANT SIZE OF THE WT

DEFINITION OF THE COLOR CONTRAST BETWEEN WT AND ENVIRONMMENT The difference in color is estimated by: ΔΕ*abs=[(ΔL*) 2 + (Δa*) 2 + (Δb*) 2 ] 1/2 where: ΔΕ*αbs : the absolute difference in color ΔL* : the difference in the luminosity Δa* and Δb* : the differences in the color parameters a* and b* of the model CIELAB (Robertson, 1977) The average color difference per pixel (ΔΕ*abs) was 34 and expressed % ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

DEFINITION OF THE IMPACT OF THE ATMOSPHERIC DISPERSION Equation Cozman & Crotkov (1997) C’= Ce -βd + S(1-e -βd ) Where C’: luminosity of the object C: luminosity of the object without dispersion S: luminosity of the sky β: reduction coefficient; β value is 0,00008 d: the distance of the object from the observer ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

DEFINITION OF THE IMPACT OF THE ATMOSPHERIC DISPERSION If C 1 is the luminosity of the WT and C 2 of the environment the initial contract (%) will be : (C 1 - C 2 )x100/256 or finally C d = C i e -βd Where C d is the understood contrast in depth d, C i the initial contrast in d=0 and d the distance (m). ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

DEFINITION OF THE VISUAL LIMITS Τhe visual limit (Shang & Bishop) is expressed through the probability: Prob = 1 / (1 + e -Z ) where Ζ can be referred on: 1. Tracing without information 2. Recognition with no information 3. Recognition with previous information 4.Average visual impact with previous information ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

EL-ZAYAT WP 100 ΜW 77 WTs; 1,3 ΜW each WT height: 60 m Distance between rows: 15D Distance between WTs 3,5D ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE WINDPRO SIMULATION MODEL

Visual simulation of the WP from point Β ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

CONCUSIONS The general public acceptance and the implementation of the project depends critically on the potential damages in the landscape and the environment The siting and the rational design of a WP is major for the wind energy exploitation The rational design as concerns WT (color, material. size, etc), but also the rational arrangement are important, although there is no ‘hi-tech’ dye or material, which wipes off the WT ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

Nowadays exist efficient methods to estimate the visual annoyance from WTs The visual simulation of the project could assist in the optimum design, but also in the satisfaction of many observers ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE

THANK YOU FOR YOUR ATTENTION! ENVIRONMENTAL ENGINEERING DEPT TECHNICAL UNIVERSITY OF CRETE