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Page 1: Abu Dhabi Climate

2 W

eath

er D

ata

The

achi

evem

ent o

f sus

tain

able

des

ign

goal

s re

ly o

n an

alys

es th

at a

re

heav

ily

depe

nden

t up

on

the

wea

ther

. H

ence

, an

ac

cura

te

and

com

preh

ensi

ve w

eath

er d

ata

set m

ust b

e us

ed fo

r all

eval

uatio

ns.

Mor

e th

an o

ne w

eath

er d

ata

set

is a

vaila

ble

for

Abu

Dha

bi:

the

IWE

C

wea

ther

dat

a, a

rtific

ially

gen

erat

ed M

eteo

norm

Dat

a, m

easu

red

data

fro

m a

n In

stitu

te a

nd m

easu

red

data

from

Tra

nsso

lar.

Due

to

the

impo

rtanc

e of

sol

ar r

adia

tion

in t

his

clim

ate,

the

dire

ct a

nd

diffu

se p

ortio

ns o

f the

sol

ar ra

diat

ion

wer

e ev

alua

ted

and

com

pare

d. A

s on

e ca

n se

e, t

he I

WEC

dat

a is

the

�“w

orst

-cas

e�” s

cena

rio f

or t

wo

reas

ons.

Firs

t, th

e in

tegr

al o

f ann

ual r

adia

tion

is th

e hi

ghes

t com

pare

d to

the

oth

er d

ata

sets

and

sec

ond,

the

dire

ct r

adia

tion

perc

enta

ge

repr

esen

ts th

e �“w

orst

-cas

e�” s

cena

rio a

s w

ell.

Ta

ble

1: C

ompa

rison

of d

iffer

ent w

eath

er d

ata

sets

inte

rmed

iate

inte

rmed

iate

gl

obal

radi

atio

n lo

wgl

obal

radi

atio

n hi

gh

sim

ilar d

ata

char

acte

ristic

sAL

Ain

tota

l rad

iatio

n an

d be

am ra

tio is

hig

her i

n co

mpa

rison

to A

bu D

habi

cau

sed

by lo

wer

Dew

Poi

nt

Tem

pera

ture

due

to u

pcou

ntry

and

des

ert l

ocat

ion

radi

atio

n ra

tion

depe

nds

sign

ifica

nt o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tion

depe

nds

sign

ifica

nt o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tio d

epen

ds

min

or o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tio d

epen

ds

min

or o

n de

w p

oint

te

mpe

ratu

re

prop

er fo

r pro

ject

s w

ith

sim

ilar g

eogr

aphi

c lo

catio

n as

Al A

in in

M

iddl

e Ea

st(u

pcou

ntry

)

prop

er fo

r pro

ject

s w

ith

sim

ilar g

eogr

aphi

c lo

catio

n as

Abu

Dha

bi in

M

iddl

e Ea

st(n

ear b

y th

e se

a)

prop

er fo

r ?pr

oper

for a

ll pr

ojec

ts w

ith

requ

irem

ents

on

air a

nd

hum

idity

sign

ifica

nt s

easo

nal

char

acte

ristic

ssi

gnifi

cant

sea

sona

l ch

arac

teris

tics

min

or s

easo

nal

char

acte

ristic

sno

sea

sona

l ch

arac

teris

tics

inte

rmed

iate

inte

rmed

iate

diffu

se ra

tio to

hig

hdi

ffuse

ratio

to lo

w

TSE

Al A

inIN

STIT

UTE

Abu

Dha

biM

NAb

u D

habi

IWE

CAb

u D

habi

inte

rmed

iate

inte

rmed

iate

gl

obal

radi

atio

n lo

wgl

obal

radi

atio

n hi

gh

sim

ilar d

ata

char

acte

ristic

sAL

Ain

tota

l rad

iatio

n an

d be

am ra

tio is

hig

her i

n co

mpa

rison

to A

bu D

habi

cau

sed

by lo

wer

Dew

Poi

nt

Tem

pera

ture

due

to u

pcou

ntry

and

des

ert l

ocat

ion

radi

atio

n ra

tion

depe

nds

sign

ifica

nt o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tion

depe

nds

sign

ifica

nt o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tio d

epen

ds

min

or o

n de

w p

oint

te

mpe

ratu

re

radi

atio

n ra

tio d

epen

ds

min

or o

n de

w p

oint

te

mpe

ratu

re

prop

er fo

r pro

ject

s w

ith

sim

ilar g

eogr

aphi

c lo

catio

n as

Al A

in in

M

iddl

e Ea

st(u

pcou

ntry

)

prop

er fo

r pro

ject

s w

ith

sim

ilar g

eogr

aphi

c lo

catio

n as

Abu

Dha

bi in

M

iddl

e Ea

st(n

ear b

y th

e se

a)

prop

er fo

r ?pr

oper

for a

ll pr

ojec

ts w

ith

requ

irem

ents

on

air a

nd

hum

idity

sign

ifica

nt s

easo

nal

char

acte

ristic

ssi

gnifi

cant

sea

sona

l ch

arac

teris

tics

min

or s

easo

nal

char

acte

ristic

sno

sea

sona

l ch

arac

teris

tics

inte

rmed

iate

inte

rmed

iate

diffu

se ra

tio to

hig

hdi

ffuse

ratio

to lo

w

TSE

Al A

inIN

STIT

UTE

Abu

Dha

biM

NAb

u D

habi

IWE

CAb

u D

habi

An

nual

Bea

m; D

iffus

e R

adia

tion

816

863

607

889

1'36

01'

198

1'59

81'

060

0.00

500.

00

1000

.00

1500

.00

2000

.00

2500

.00

AA_T

SEA

D_D

LRAD

_IW

ECAD

_MN

Annual Radiation [kWh/m²]

Bea

mD

iffus

e

63%

58%

72%

54%

37%

42%

28%

46%

+33%

+14%

-12%

TSE

Inst

itute

IWEC

MN

Fi

gure

1: S

olar

radi

atio

n co

mpa

rison

A

vera

ge T

Am

bien

t

0.00

5.00

10.0

0

15.0

0

20.0

0

25.0

0

30.0

0

35.0

0

40.0

0

Jan

Feb

Mrz

Apr

Mai

Jun

Jul

Aug

Sep

Okt

Nov

Dez

Year

T_amb [°C]

AA_

TSE

AD

_DLR

AD

_IW

ECA

D_M

N

INST

Fi

gure

2: A

mbi

ent t

empe

ratu

re c

ompa

rison

A

vera

ge T

Dew

poin

t

0.00

5.00

10.0

0

15.0

0

20.0

0

25.0

0

30.0

0

Jan

Feb

Mrz

Apr

Mai

Jun

Jul

Aug

Sep

Okt

Nov

Dez

Year

T_dew [°C]

AA_

TSE

AD

_DLR

AD

_IW

ECA

D_M

N

INST

Fi

gure

3: A

mbi

ent d

ewpo

int c

ompa

rison

Page 2: Abu Dhabi Climate

3 O

utdo

or C

omfo

rt R

atin

g Th

e Pe

rcei

ved

Tem

pera

ture

(PT

) is

an

appr

opria

te m

easu

re t

o ra

te

outd

oor

com

fort

sinc

e al

l do

min

atin

g en

viro

nmen

tal

para

met

ers

are

cons

ider

ed.

The

fou

r m

ajor

clim

atic

par

amet

ers

that

affe

ct t

herm

al

com

fort

are:

- a

ir te

mpe

ratu

re

- air

hum

idity

- w

ind

spee

d

- mea

n ra

dian

t tem

pera

ture

Ad

ditio

nal

para

met

ers

incl

udin

g th

e in

sula

tion

prop

ertie

s of

clo

thin

g w

orn

and

the

activ

ity ra

te (s

ittin

g or

runn

ing)

are

par

t of t

he P

T eq

uatio

n as

wel

l. B

ased

on

thes

e pa

ram

eter

s th

e ou

tdoo

r co

mfo

rt m

odel

was

de

velo

ped.

Fi

gure

4: S

ketc

h - o

utdo

or c

omfo

rt p

aram

eter

s

In h

ot a

nd h

umid

clim

ates

, pe

rcei

ved

tem

pera

ture

s of

32°

C o

r lo

wer

are

ra

ted

as e

xcel

lent

for

out

door

com

fort,

not

ed i

n th

is r

epor

t in

gre

en.

Perc

eive

d te

mpe

ratu

res

betw

een

32°C

and

38°

C, n

oted

in y

ello

w, a

re ra

ted

hot

and

perc

eive

d te

mpe

ratu

res

abov

e 38

°C

indi

cate

s ve

ry

hot

tem

pera

ture

s, n

oted

in re

d.

The

annu

al P

T ev

alua

tion

is b

ased

on

the

data

der

ived

fro

m t

he I

WE

C

wea

ther

dat

a se

t for

Abu

Dha

bi (s

ee c

hapt

er o

n cl

imat

e an

alys

is).

Ta

ble

2: O

utdo

or c

omfo

rt c

ateg

ory

grou

ps

The

Perc

eive

d Te

mpe

ratu

re m

odel

ass

umes

tha

t pe

ople

will

adju

st t

heir

clot

hing

fact

or fo

r co

ld te

mpe

ratu

res.

The

follo

win

g di

agra

m d

emon

stra

tes

the

corr

elat

ion

betw

een

PT

and

clot

h fa

ctor

. Fo

r exa

mpl

e, p

eopl

e ch

oose

a

clot

hing

fact

or o

f 1 (f

ull b

usin

ess

suit)

for p

erce

ived

tem

pera

ture

s of

12°

C.

Fi

gure

5: P

erce

ived

tem

pera

ture

and

clo

thin

g co

rrel

atio

n

Page 3: Abu Dhabi Climate

Win

d Th

e Ab

u D

habi

wea

ther

dat

a se

t sho

ws

the

prev

ailin

g w

ind

from

nor

th-

wes

t (o

ff-se

a w

inds

). Th

is i

s co

nclu

ded

from

the

com

paris

on o

f tw

o w

eath

er d

ata

sets

(IW

EC a

nd m

easu

red

data

from

an

Inst

itute

), bo

th o

f w

hich

ind

icat

e th

e sa

me

north

-wes

t pr

evai

ling

win

d. S

ince

the

IW

EC

da

ta s

et is

the

mos

t ba

lanc

ed,

it w

as s

elec

ted

for

the

eval

uatio

ns t

hat

follo

w.

Abu

Dha

bi w

ind

data

set

sho

ws

high

ly fr

eque

nt a

nd s

trong

win

ds fr

om

the

sea

mai

nly

durin

g af

tern

oon

and

even

ing.

Suc

h of

f-sea

win

ds a

re

usua

lly h

umid

, whe

reas

at n

ight

and

in m

orni

ng h

ours

, dec

reas

ed w

ind

spee

ds a

nd fr

eque

ncie

s ar

e ch

arac

teris

tic fo

r Abu

Dha

bi.

Fi

gure

6: E

valu

ated

tim

e pe

riod:

24/

7 - I

WEC

dat

a

Fi

gure

7: E

valu

ated

tim

e pe

riod:

24/

7 - m

easu

red

data

from

Inst

itute

win

d ro

se: i

wec

_abu

_dha

bi

0

200

400

600

800

1000

1200

20°

40°

60°

80°

100°

120°

140°

160°

180°

200°

220°

240°

260°

280°

300°

320°

340°

v_W

ind

>0.5

m/s

v_W

ind

>3.5

m/s

v_W

ind

>6.5

m/s

v_W

ind

>9.5

m/s

v_W

ind

>12.

5 m

/s

wes

tea

st

sout

h

nort

h

Fi

gure

8: E

valu

ated

tim

e pe

riod:

1pm

to 9

pm (A

FTER

NO

ON

/EVE

NIN

G)

– IW

EC d

ata

win

d ro

se: i

wec

_abu

_dha

bi

0

200

400

600

800

1000

1200

20°

40°

60°

80°

100°

120°

140°

160°

180°

200°

220°

240°

260°

280°

300°

320°

340°

v_W

ind

>0.5

m/s

v_W

ind

>3.5

m/s

v_W

ind

>6.5

m/s

v_W

ind

>9.5

m/s

v_W

ind

>12.

5 m

/s

wes

tea

st

sout

h

nort

h

Fi

gure

9: E

valu

ated

tim

e pe

riod:

9pm

to 5

am (N

IGH

T) –

IWEC

dat

a w

ind

rose

: iw

ec_a

bu_d

habi

0

200

400

600

800

1000

1200

20°

40°

60°

80°

100°

120°

140°

160°

180°

200°

220°

240°

260°

280°

300°

320°

340°

v_W

ind

>0.5

m/s

v_W

ind

>3.5

m/s

v_W

ind

>6.5

m/s

v_W

ind

>9.5

m/s

v_W

ind

>12.

5 m

/s

wes

tea

st

sout

h

nort

h

Fi

gure

10:

Eva

luat

ed ti

me

perio

d: 5

am to

1pm

(MO

RN

ING

) – IW

EC

data

Page 4: Abu Dhabi Climate

Perc

eive

d Te

mpe

ratu

re P

sych

rom

etric

Cha

rts

Eval

uatio

n Th

e di

agra

ms

belo

w s

how

out

door

com

fort

(per

ceiv

ed t

empe

ratu

res)

ba

sed

on a

mon

thly

eva

luat

ion

of v

ario

us o

utdo

or c

omfo

rt st

rate

gies

. Th

e am

bien

t air

tem

pera

ture

is r

epre

sent

ed w

ith d

ots.

Th

e bl

ue, g

reen

an

d pi

nk d

ots

diffe

rent

iate

the

tem

pera

ture

s sp

ecifi

c to

the

mon

th

(bet

wee

n 6a

m a

nd 1

0pm

) fro

m th

e pe

ach

dots

, whi

ch r

epre

sent

the

air

tem

pera

ture

s in

the

rem

aind

er o

f the

yea

r. T

he c

olou

red

cont

our

lines

re

pres

ent p

erce

ived

tem

pera

ture

s sp

ecifi

c to

the

com

fort

stra

tegy

. Th

e ke

y is

alo

ng t

he r

ight

sid

e of

the

dia

gram

. W

hile

the

red

line

alw

ays

repr

esen

ts a

PT

of 3

8°C

, th

e ye

llow

32°

C,

etc,

not

e th

at t

he s

hape

of

each

line

cha

nges

as

com

fort

stra

tegi

es a

re a

pplie

d.

It is

hel

pful

to

first

und

erst

and

the

diag

ram

s fo

r th

e ba

se c

ase.

Fo

r ex

ampl

e, 6

4.7%

of t

he a

mbi

ent t

empe

ratu

res

in J

anua

ry w

ill yi

eld

a PT

belo

w 3

2°C

; th

is i

s gr

aphi

cally

sho

wn

by t

he b

lue

dots

fal

ling

belo

w t

he

yello

w c

onto

ur l

ine.

35

.3%

of

the

ambi

ent

tem

pera

ture

s in

Jan

uary

will

yi

eld

a P

T be

twee

n 32

°C a

nd 3

8°C

; thi

s is

gra

phic

ally

sho

wn

by th

e gr

een

dots

fal

ling

betw

een

the

yello

w a

nd r

ed li

nes.

Fi

nally

, 0%

of

the

ambi

ent

tem

pera

ture

s in

Jan

uary

will

yiel

d a

PT

abov

e 38

°C (

no p

ink

dots

). A

s th

e ye

ar p

rogr

esse

s, th

e nu

mbe

r of

am

bien

t tem

pera

ture

s yi

eldi

ng a

PT

abov

e 38

°C in

crea

ses

and

is s

how

n in

pin

k (s

ee J

uly

Base

Cas

e w

here

97.

3% o

f th

e m

onth

lies

abo

ve th

e re

d lin

e).

To

und

erst

and

the

impr

ovem

ent

caus

ed b

y co

mfo

rt st

rate

gies

suc

h as

sh

adin

g an

d ai

r mov

emen

t, co

mpa

re th

e sh

ape

of th

e co

ntou

r lin

es fo

r eac

h m

onth

. Fo

r exa

mpl

e, th

e PT

line

s m

ove

to th

e rig

ht w

hen

shad

ing

is a

dded

, so

tha

t fo

r an

am

bien

t co

nditi

on o

f 30

°C a

nd h

umid

ity r

atio

of

10 g

/kg

in

Janu

ary,

whi

ch y

ield

ed a

PT

abov

e 32

°C f

or t

he b

ase

case

, no

w y

ield

s a

PT b

elow

32°

C w

hen

shad

ing

is i

mpl

emen

ted.

Fu

rther

, co

nsid

er t

he

num

ber

of p

oint

s w

here

the

PT is

gre

ater

than

38°

C in

Jul

y (9

7.3%

). W

ith

the

addi

tion

of s

hadi

ng a

nd a

ir m

ovem

ent,

the

perc

ent

of t

he y

ear

whe

re

PT is

gre

ater

than

38°

C is

redu

ced

to 5

0.7%

, a d

ram

atic

effe

ct.

Figu

re 1

1: M

onth

ly p

sych

omet

ric c

hart

s

Page 5: Abu Dhabi Climate

4 O

utdo

or C

omfo

rt E

valu

atio

n As

des

crib

ed in

the

prev

ious

cha

pter

, the

out

door

com

fort

eval

uatio

n is

ba

sed

on p

erce

ived

tem

pera

ture

s: th

e in

crea

se o

f the

num

ber

of h

ours

m

ade

mor

e liv

able

ar

e pr

esen

ted

in

the

redu

ctio

n of

pe

rcei

ved

tem

pera

ture

s ab

ove

38°C

. In

thi

s ch

apte

r va

rious

met

hods

for

impr

ovin

g ou

tdoo

r th

erm

al c

omfo

rt ar

e de

scrib

ed

in

deta

il.

The

inte

ntio

n he

re

is

to

prov

ide

deta

iled

info

rmat

ion

and

eval

uatio

n fo

r ea

ch a

ppro

ach.

The

prin

cipl

es f

or e

ach

appr

oach

are

des

crib

ed b

y a

sket

ch a

nd e

xam

ples

. B

ase

Cas

e Sc

enar

io

The

base

sce

nario

for

the

per

ceiv

ed t

empe

ratu

re e

valu

atio

ns i

n th

is

repo

rt in

clud

es a

per

son

stan

ding

fro

m m

orni

ng t

o ev

enin

g (6

am t

o 10

pm)

on a

stre

et r

ecei

ving

ful

l so

lar

radi

atio

n an

d al

mos

t no

win

d (a

ssum

ed

aver

age

win

d sp

eed

of

0.1

m/s

). S

uch

a pe

rson

w

ill

expe

rienc

e ve

ry

hot

tem

pera

ture

s fo

r 31

.6

%

of

the

year

, ho

t te

mpe

ratu

res

for 2

4.8

% o

f the

yea

r and

com

forta

ble

outd

oor c

ondi

tions

on

ly 4

3.7

% o

f the

yea

r.

43.7

%

24.8

%

31.6

%

0%10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Bas

e C

ase

Perceived Temperature Level

PT >

= 38

32 <

= PT

<38

PT <

32

Eval

uatio

n pe

iod:

mor

ning

and

afte

rnoo

n (6

am to

10p

m)

Fi

gure

12:

Bas

elin

e ou

tdoo

r com

fort

Sh

adin

g st

rate

gies

Th

e be

st s

trate

gy t

o in

crea

se o

utdo

or t

herm

al c

omfo

rt is

a g

roup

of

trees

, fol

low

ed b

y a

shad

ing

devi

ce w

ith lo

w s

olar

tran

smitt

ance

. If t

he

shad

ing

syst

em c

an b

e re

mov

ed d

urin

g ni

ght t

imes

(op

erab

le s

hadi

ng)

the

bene

fit i

ncre

ases

, be

caus

e su

ch a

sys

tem

wou

ld a

llow

for

nig

ht

purg

e of

the

sol

ar e

nerg

y st

ored

in

mas

sive

stru

ctur

es l

ike

stre

ets,

fa

cade

s, e

tc.

Sha

ding

stra

tegi

es h

ave

the

pote

ntia

l to

be

depl

oyed

in

vario

us l

ocat

ions

. A

ll sh

adin

g op

tions

are

pas

sive

too

ls,

beca

use

no

addi

tiona

l po

wer

is

need

ed t

o ac

hiev

e th

e im

prov

emen

t in

out

door

co

mfo

rt. E

ven

retra

ctab

le s

yste

ms

coul

d w

ork

man

ually

. A

ir m

ovem

ent

The

air

mov

emen

t ap

proa

ch is

wor

th e

valu

atio

n as

wel

l, w

heth

er it

be

mec

hani

cally

gen

erat

ed o

r cr

eate

d by

the

win

d. A

ir m

ovem

ent h

as th

e po

tent

ial

to i

mpr

ove

com

fort

durin

g m

ost

seas

ons,

but

als

o de

crea

se

outd

oor

com

fort

durin

g th

e ho

ttest

and

mos

t hum

id m

onth

. The

refo

re a

wel

l th

ough

t ou

t sy

stem

nee

ds t

o be

dev

elop

ed.

The

phys

ical

prin

cipl

e be

hind

all

the

appr

oach

es is

to c

reat

e tu

rbul

ence

and

air

velo

city

, whi

ch w

ill

resu

lt in

hig

her h

eat t

rans

fer r

ate

of th

e bo

dy a

nd e

vapo

rativ

e co

olin

g at

the

skin

. H

ot a

nd h

umid

win

ds c

an c

reat

e th

e op

posi

te a

nd,

henc

e, n

egat

ive

effe

ct,

not

allo

win

g th

e bo

dy

to

evap

orat

e fo

r co

olin

g pu

rpos

es.

Figu

re 1

3: O

utdo

or c

omfo

rt to

ols

Page 6: Abu Dhabi Climate

Out

door

com

fort

mat

rix

The

outd

oor

com

fort

mat

rix s

how

s at

a g

lanc

e al

l ou

tdoo

r co

mfo

rt st

rate

gies

eva

luat

ed fo

r the

Lul

u Is

land

pro

ject

. Th

e ou

tdoo

r co

mfo

rt st

rate

gies

are

sub

divi

ded

into

the

mai

n pr

inci

ples

ho

w to

impr

ove

ther

mal

com

fort.

The

se a

ppro

ache

s ar

e:

- Sh

adin

g pr

inci

ples

-

Air m

ovem

ent

- C

ombi

natio

n of

sha

ding

and

air

mov

emen

t

Figu

re 1

4: O

utdo

or c

omfo

rt to

ol m

atrix

Shad

ing

from

M

ultip

le T

rees

Shad

ing

from

a

Sing

le T

ree

30%

Fix

ed

Shad

e

15%

Fix

ed

Shad

e

2% F

ixed

Sh

ade

Incr

ease

d A

ir M

ovem

ent a

nd

2% F

ixed

Sha

de

Incr

ease

d A

ir M

ovem

ent

Page 7: Abu Dhabi Climate

Air

Mov

emen

t D

efin

ition

/ D

escr

iptio

n Ai

r m

ovem

ent

is a

n im

porta

nt f

acto

r in

im

prov

ing

outd

oor

com

fort.

H

owev

er,

this

app

roac

h ne

eds

to b

e co

nsid

ered

tho

ught

fully

, si

nce

hum

id a

nd h

ot w

inds

will

actu

ally

dec

reas

e ou

tdoo

r com

fort.

Hen

ce, t

he

seas

onal

dep

ende

ncy

of t

his

appr

oach

nee

ds t

o be

con

side

red

and

inte

grat

ed in

to th

e de

sign

. G

ener

atin

g or

cat

chin

g w

ind

can

be a

chie

ved

with

var

ious

tech

nolo

gies

an

d tra

ditio

nal

met

hods

, lik

e fla

ps,

fans

, w

indt

ower

s,

defle

ctin

g w

inds

ails

, et

c. T

he p

hysi

cal

prin

cipa

l is

alw

ays

the

sam

e, w

hich

is

crea

ting

turb

ulen

ce a

nd p

rovi

ding

the

hum

an b

ody

the

chan

ce t

o lo

se

heat

mor

e ef

ficie

ntly

. B

est P

ract

ice

Exam

ples

Fi

gure

15:

The

win

d ca

tche

r ha

s a

long

tra

ditio

n in

thi

s re

gion

. A

lthou

gh t

he d

esig

n m

ay v

ary

in c

ount

ries,

the

maj

or p

rinci

ples

st

ayed

the

sam

e. T

his

tech

nolo

gy w

as u

sed

to c

ondi

tion

and

optim

ize

the

inte

rior

spac

es

whe

n am

bien

t co

nditi

ons

wer

e un

plea

sant

.

Fi

gure

16:

Ske

tch

– re

dire

ctio

n of

air

flow

due

to

build

ing

heig

ht

diffe

renc

e

Figu

re 1

7: A

ir m

ovem

ent

43.7

%51

.9%

24.8

%

20.7

%

31.6

%27

.4%

0.0%

10.0

%

20.0

%

30.0

%

40.0

%

50.0

%

60.0

%

70.0

%

80.0

%

90.0

%

100.

0%

Bas

e C

ase

Air M

ovem

ent

PT >

= 38

32 <

= PT

<38

PT <

32

13.3

% R

educ

tion

Eval

uatio

n pe

iod:

mor

ning

and

afte

rnoo

n (6

am to

10p

m)

Page 8: Abu Dhabi Climate

Fi

xed

shad

ing

syst

em (t

rans

mitt

ance

2%

, 15%

, 30%

) D

efin

ition

/ D

escr

iptio

n O

utdo

or s

hadi

ng i

s an

effe

ctiv

e ap

proa

ch t

o im

prov

e ou

tdoo

r co

mfo

rt es

peci

ally

in a

clim

ate

such

as

Abu

Dha

bi. A

n ef

fect

ive

shad

ing

syst

em

has

the

pote

ntia

l to

red

uce

very

hot

per

ceiv

ed t

empe

ratu

res

by m

ore

than

60

%.

How

ever

, a

low

tra

nsm

ittan

ce m

ater

ial n

eeds

to

be u

sed.

Su

ch lo

w t

rans

mitt

ance

can

be

achi

eved

by

laye

ring

diffe

rent

sha

ding

st

ruct

ures

or

usin

g op

aque

mat

eria

ls w

ith i

ncor

pora

ted

stru

ctur

e. A

sh

adin

g de

vice

with

hig

her s

olar

tran

smitt

ance

will

dec

reas

e th

e am

ount

of

com

forta

ble

situ

atio

ns.

Bes

t Pra

ctic

e Ex

ampl

es

Fi

gure

18:

A s

hopp

ing

mal

l in

Lisb

on fe

atur

es a

n ET

FE ro

of w

ith a

so

lar t

rans

mitt

ance

of a

bout

2%

for t

he e

xter

ior o

paqu

e la

yer.

This

is

ach

ieve

d by

2 w

hite

ETF

E fo

ils a

nd a

dditi

onal

coa

ting

betw

een

the

laye

rs.

Fi

gure

19:

The

his

toric

city

of D

amas

cus

is s

hade

d by

fixe

d sh

adin

g w

ith a

dditi

onal

pla

ntin

gs to

incr

ease

ther

mal

com

fort

.

Figu

re 2

0: S

hadi

ng

43.7

%

64.2

%60

.8%

52.5

%

24.8

%

23.9

%24

.9%

27.1

%

31.6

%

11.9

%14

.3%

20.4

%

0.0%

10.0

%

20.0

%

30.0

%

40.0

%

50.0

%

60.0

%

70.0

%

80.0

%

90.0

%

100.

0%

Bas

e C

ase

Shad

ing

2%Sh

adin

g 15

%Sh

adin

g 30

%

PT >

= 38

32 <

= PT

<38

PT <

32

Eval

uatio

n pe

iod:

mor

ning

and

afte

rnoo

n (6

am to

10p

m)

62.3

%

Red

uctio

n54

.7%

R

educ

tion

35.4

%

Red

uctio

n

Page 9: Abu Dhabi Climate

Tr

ee

G

roup

of t

rees

D

efin

ition

/ D

escr

iptio

n A

tree

has

a hi

gh p

oten

tial

to r

educ

e th

e pe

rcei

ved

tem

pera

ture

. H

owev

er,

one

sing

le

tree

has

limite

d sh

adin

g po

tent

ial.

For

the

perc

eive

d te

mpe

ratu

re e

valu

atio

n w

e as

sum

ed a

per

son

stan

ding

in th

e sh

ade

of a

tre

e be

twee

n 9.

00 a

nd 1

2.00

, w

here

as f

or t

he o

ther

hou

rs

the

pers

on i

s st

andi

ng i

n di

rect

sun

. Th

e tre

e sh

adin

g ap

proa

ch h

as

mul

tiple

ben

efits

. Th

e tre

e tri

es t

o ke

ep t

he c

ore

tem

pera

ture

on

a co

nsta

nt l

evel

to

surv

ive.

The

abs

orbe

d so

lar

ener

gy i

s us

ed f

or t

he

phot

osyn

thes

is p

roce

ss, w

hich

turn

s th

e ab

sorb

ed e

nerg

y in

to n

utrit

ion

and

oxyg

en.

As

the

tree

evap

orat

es w

ater

to

cool

the

lea

ves,

a s

elf-

cool

ing

prin

cipl

e, t

he r

adia

nt t

empe

ratu

re b

elow

the

tre

e is

red

uced

. Th

is e

ffect

is w

hat p

eopl

e pe

rcei

ve w

hile

sitt

ing

belo

w a

tree

. In

par

alle

l, a

grou

p of

tree

s w

ill s

hade

a p

erso

n al

l day

, sin

ce th

ey w

ill

be s

urro

unde

d by

man

y tre

es.

This

res

ults

in a

sig

nific

ant

incr

ease

in

ther

mal

com

fort:

Dur

ing

the

dayt

ime,

the

unb

eara

ble

cond

ition

s ar

e re

duce

d fro

m m

ore

than

80%

to o

nly

6.3%

per

yea

r. B

est P

ract

ice

Exam

ples

Fi

gure

21:

The

imag

e sh

ows

a lo

cal s

hadi

ng s

trat

egy

with

a tr

ee in

O

man

.

Fi

gure

22:

Thi

s pa

rk is

loca

ted

in R

onda

a c

ity in

the

sout

h of

Spa

in

with

a s

peci

al c

limat

e si

tuat

ion.

Alth

ough

Ron

da is

loca

ted

alm

ost

750

m a

bove

sea

lev

el,

the

clim

ate

show

s ve

ry w

arm

and

hum

id

clim

ate

situ

atio

ns.

Ther

efor

e th

e sh

adin

g pr

inci

ple

can

be f

ound

at

vario

us lo

catio

ns th

roug

hout

the

city

.

Fi

gure

23:

Tre

es

43.7

%

57.9

%

71.4

%

24.8

%

25.2

%

22.2

%31

.6%

16.9

%6.

3%

0.0%

10.0

%

20.0

%

30.0

%

40.0

%

50.0

%

60.0

%

70.0

%

80.0

%

90.0

%

100.

0%

Bas

e C

ase

Tree

Gro

up o

f tre

es

PT >

= 38

32 <

= PT

<38

PT <

32

Eval

uatio

n pe

iod:

mor

ning

and

afte

rnoo

n (6

am to

10p

m)

46.5

%

Red

uctio

n80

.1%

R

educ

tion

Page 10: Abu Dhabi Climate

Sh

adin

g an

d A

ir M

ovem

ent

Def

initi

on /

Des

crip

tion

A co

mbi

natio

n of

bot

h sh

adin

g an

d ai

r m

ovem

ent

syst

ems

is f

easi

ble

and

wou

ld re

duce

ver

y ho

t per

ceiv

ed te

mpe

ratu

res

by a

bout

50

%. T

he

resu

lts

show

ve

ry

clea

rly

that

du

ring

hot

and

hum

id

perio

ds

air

mov

emen

t is

not b

enef

icia

l (se

e Fi

gure

24)

. Th

is is

due

to th

e fa

ct th

at

the

shad

ing

optio

ns a

lone

red

uce

very

hot

tem

pera

ture

s by

mor

e th

an

60 %

, w

hile

the

com

bina

tion

of s

hadi

ng a

nd a

ir m

ovem

ent

achi

eves

a

redu

ctio

n of

onl

y 50

%.

Hen

ce,

a us

er

cont

rolle

d an

d se

ason

al

air

mov

emen

t de

sign

is

ne

cess

ary,

so

that

the

out

door

com

fort

stra

tegi

es d

o no

t co

unte

ract

ea

ch o

ther

.

Fi

gure

24:

Win

d ca

lend

ar

Bes

t Pra

ctic

e Ex

ampl

es

Fi

gure

25:

Ske

tch

of s

hadi

ng a

nd a

ir m

ovem

ent p

rinci

ple

Figu

re 2

6: S

hadi

ng a

nd a

ir m

ovem

ent

43.7

%

63.5

%

24.8

%

21.3

%

31.6

%

15.3

%

0.0%

10.0

%

20.0

%

30.0

%

40.0

%

50.0

%

60.0

%

70.0

%

80.0

%

90.0

%

100.

0%

Bas

e C

ase

Shad

ing

+ Ai

r Mov

emen

t

PT >

= 38

32 <

= PT

<38

PT <

32

Eval

uatio

n pe

iod:

mor

ning

and

afte

rnoo

n (6

am to

10p

m)

51.6

% R

educ

tion


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