iccsa08 petri wind

Renewable energy sources: the case of wind farms analysis

Renewable energy sources: the case of wind farms analysis

Massimiliano PETRI Silvana LOMBARDO

L.I.S.T.A. – Laboratorio di Ingegneria dei Sistemi Territoriali e Ambientali

University of Pisa, Department of Civil Engineering

[email protected]@ing.unipi.it


Italian state of the art

1) Lack of national guidelines

2) Systematic and strategic planning rarely applied

3) Local authorities limited to the approval or denial of private proposals

4) No shareable methodology.


Objective

To develop methods and techniques aimed to

produce systematic and integrated knowledge on

the possibility of production and sustainable use of

renewable energy sources.

General objective


Method Study area

In S.Luce Municipalities (in the Province of Pisa, in Tuscany Region):

• Poggio Nebbie hill• Prunicce hill


Method Some remarks

"Landscape" means an area, as perceived by people, whose character is the result ….

The assessment of wind turbine generators impact on the landscape is not simple, taking into account the meaning of landscape, as described in the first article of the European Landscape Convention:


The general methodology

Phase A

Analysis at the wide scale

Phase B

Local impact assessment of each possible locations


Method

Visual impact area identification (AVI)

Phase A1 - Analysis at the wide scale

Maximum visibility radius Rv

1. Visibility analysis based on existing wind farm (observers at three distances: 23, 20 and 17.5 km);

2. Human eye real perceptive capacity analysis;

3. Earth's curvature influence analysis;

4. Visibility analysis of data measured at Pisa Airport (correlation of visibility with relative humidity);


Method

Visibility analysis based on existing wind farm

1 23 km distance

2 20 km distance

3 17 km distance



Method

Earth curvature analysis

Expression of the Hydrographic Institute of Italian Navy:

D = 2.04 (e1/2 + E1/2 ) [m]

649 m s.l.m.

MVD - Maximum visibility distance

e = observer absolute heightE = target absolute height (wind turbine)

quote

DMV

e ED

e ED



Visibility analysis of data measured at Pisa Airport

Method

0

2

4

6

8

10

12

0 2000 4000 6000 8000 10000 12000 14000

distanza [m] .

alte

zza

[m]

.

30%40%50%60%70%80%90%100%

c100% 0.1390% 0.2580% 0.3770% 0.5060% 0.6350% 0.7540% 0.8730% 1.00

MVD MultiplierFactors

Correlation of visibility with relative humidity



Method

Visual Impact Area (AVI)


a radius of 25 km


Method

Environmental and socio-economic data analysis inside the AVI1) Wind maps2) National, regional and provincial prescriptive constraints;3) Environmental sensitivity relating to :

I. Fauna• Presence of migratory course• Presence of important wintering species

II. Flora• Presence of important species

III. Air (sound pollution, presence of buildings, etc..);IV. Soil and subsoil (geomorphologic and hydraulic dangerousness)V. Landscape and historic/architectonic public property

• Presence of landscape attractive/detractive elements;• Historical Index;• Shannon’s Index (landscape mosaic fragmentation level);• Hill’s Index (predominance of particular land use);• Sharpe’s Change Index (land use dynamics);• Visibility analysis (“visual frequency” and visual field analysis)

VI. Infrastructure (distance from roads and from the power station)



Method

Wind Maps

vel. media k cgennaio 5.408 1.655 6.050febbraio 7.213 1.759 8.102marzo 6.689 1.903 7.538aprile 6.393 2.126 7.219

maggio 6.612 2.005 7.461giugno 5.285 1.881 5.953luglio 8.440 2.025 9.525

agosto 5.324 1.486 5.891settembre 5.462 2.041 6.165

ottobre 7.291 1.313 7.910novembre 7.602 1.757 8.538dicembre 7.997 1.886 9.010

W = Cp (cf) * V3 * R2

mean speedmonth



Method

Visibility Sensitivity Analysis

Construction of the possible observers

Visibility analysis



Method


For each height level three Visibility Maps was calculated:

- Visibility of observers located in the main streets;- Visibility of observers located in the touristic and natural streets (pathways, streets for trekking, muletracks, etc..);

- Visibility of observers located in urban centers

DTM20 mt

120 mt

40 mtX mt

The visibility of the single generator can be also partial so it was calculated for different height levels (every 20 meters)



Method


“Horizontal” aggregation

0.150.350.5Weights

Drivers visibilityVisibility fromurban centers

Visibility frompathways

10.80

2R

“Vertical” aggregation



Phase B - Local impact assessment Method

“Height visibility levels” evaluation

A prototypical generator 100 meters high was simulated by means of a GIS software in each locations resulting from Phase A and every ten meters along each generator a target point has been located.For each cell inside the AVI the number of visible target points was calculated


Phase B1 - Local impact assessment Method

“Height visibility levels” evaluation

Poggio al Tiglio HillPoggio Castagnola Hill



Important observer points of view individuation

From the overlay of the visibility maps and the spatial distribution of observers inside the AVI, it was possible to identify the areas having a greater visual impact.



Landscape quality factors individuation and reconstruction

The landscape quality has been evaluated with the individuation of detractive and attractive landscape elements

Environmental Factors Criteria Data

Urban area built before 1954 Urban area built before 1878

Crumbling ruins Civil architecture of great value

Religious architecture Rural architecture

Tabernacles and isolated crosses Monuments

Architectonic domains

Anthropic elements

Others Parks Protected areas Nature reserves

Olive grove (and rows) Vineyard (and rows) Orchard (and rows)

Chestnut grove

Agricultural elements

Tree Rows Geologic high value elements

Ridge grasslands Rocky outcrops

Riparian associations

Att

ract

ive

elem

ents

Natural elements

Wood boundaries Shacks

Hothouses Power stations

Electrical boxes Filling station

Abandoned quarries Working quarriess

Special isolated buildings Cableways

Purification plants Chimneys

Anthropic elements

Others Main streets

Lan

dsca

pe q

ualit

y el

emen

ts

Det

ract

ive

elem

ents

Transport elements Railways



Landscape perceived quality reconstruction

For each observer we reconstructed the individual visual sceneby overlapping the visible area withdetractive and attractive landscape elements.


THE END

Massimiliano [email protected]

Silvana [email protected]

University of PisaDepartment of Civil Engineering

Thank you !!

iccsa08 petri wind

Technology