Acco di g
to
Scie ce
Di ect,
the
hospital’s
a ual
cooli g
dema d
is
about
1,000
MWh.
A
hospital
i
ce t al
Swede
fou d
a
u usual
way
to
meet
its
summe
cooli g
eeds
by
sto i g
s ow
f om
wi te
a d
usi g
it
mo ths
late .
The
Su dsvall
Regio al
Hospital
uses
a
la ge
s ow
sto age
system
desig ed
to
p ese ve
wi te
cold
u til
the
wa me
mo ths.The
Su dsvall
hospital
has
a
floo
a ea
of
190,000
squa e
met es.
Acco di g
to
Scie ce
Di ect,
the
hospital’s
a ual
cooli g
dema d
is
about
1,000
MWh,
with
a
maximum
cooli g
powe
equi eme t
of
1,500
kW.
The
local
autho ities
we e
looki g
fo
a
cooli g
solutio
that
fitted
e vi o me tal
ta gets
a d
atio al
egulatio s.The
fi di gs
of
the
p oject
we e
published
i
a
2001
esea ch
pape
by
Kjell
Skogsbe g
a d
Bo
No dell
i
Cold
Regio s
Scie ce
a d
Tech ology.
A
la ge
s ow
sto age
a ea
The
s ow
sto age
facility
was
built
i
1999.
It
cove ed
a
a ea
measu i g
140
met es
by
60
met es
a d
had
a
total
capacity
of
60,000
cubic
met es,
equal
to
about
40,000
to es
of
s ow.At
the
begi i g
of
the
p oject,
o ly
about
half
of
the
total
sto age
capacity
was
expected
to
be
used.
The
sto age
a ea
was
built
as
a
shallow
pit
with
a
wate tight
asphalt
base.The
system
was
desig ed
to
slow
dow
the
atu al
melti g
of
the
s ow.
A
laye
of
wood
chips
was
placed
ove
the
sto ed
s ow
to
act
as
the mal
i sulatio .
Acco di g
to
the
epo t,
this
educed
atu al
melti g
to
about
20%
to
30%
of
the
total
s ow
volume.The
esea che s
also
studied
how
much
i sulatio
was
eeded
to
keep
the
s ow
available
th ough
the
summe .
Thei
simulatio s
focused
o
a
30,000-cubic-met e
s ow
sto age
facility.
How
s ow
ca
sto e
cooli g
S ow
a d
ice
melt
at
0°C,
a d
melti g
equi es
a
sig ifica t
amou t
of
heat.
Heat
f om
the
su ou di gs
is
abso bed
as
the
s ow
melts.
This
mea s
that
the
sto ed
s ow
ca
act
as
a
sou ce
of
cooli g
whe
its
meltwate
is
ci culated
th ough
a
cooli g
system.The
esea che s
looked
at
the
amou t
of
heat
eeded
to
wa m
ice,
melt
it
a d
the
wa m
the
esulti g
wate .
This
i volved
the
heat
capacity
of
ice,
the
heat
of
fusio
of
wate
a d
the
heat
capacity
of
wate .The
hospital
system
used
meltwate
athe
tha
di ectly
ci culati g
the
s ow.
Wate
f om
the
s ow
sto age
was
pumped
to
the
hospital.
Afte
the
wate
helped
cool
the
hospital,
the
wa me
wate
was
se t
back
to
the
s ow
sto age
a ea.
This
c eated
a
cycle
i
which
the
sto ed
s ow
supplied
the
cooli g
while
g adually
melti g.
A
sto age
a ea
of
140×60
m
with
a
capacity
fo
60,000
m3
(40,000
to s)
of
s ow
was
co st ucted
i
1999.
Impo ta ce
of
i sulatio
Without
i sulatio ,
the
sto ed
s ow
would
ot
have
lasted
th ough
the
summe .
The
esea che s
calculated
that
a
u i sulated
30,000-cubic-met e
s ow
pile
would
have
disappea ed
by
Ju e
17.
That
would
have
bee
well
befo e
the
e d
of
the
hospital’s
cooli g
seaso .They
the
compa ed
the
esults
whe
sawdust
was
used
as
i sulatio .
With
a
0.10-met e
laye
of
sawdust,
about
12,169
cubic
met es
of
s ow
emai ed
i
the
simulatio .
With
a
0.20-met e
laye ,
about
19,040
cubic
met es
emai ed.
The
thicke
laye
pe fo med
bette
because
it
educed
heat
t a sfe
f om
the
su ou di g
e vi o me t
i to
the
s ow.With
0.20
met es
of
sawdust,
the
maximum
atu al
meltwate
ate
was
calculated
at
77.4
cubic
met es
pe
day.
This
occu ed
towa ds
the
e d
of
Ju e.The
study
co cluded
that
with
the mal
i sulatio ,
the
sto ed
s ow
could
cove
the
hospital’s
cooli g
dema d
f om
May
to
August.
How
cooli g
was
do e
ea lie
The
esea che s
also
oted
that
people
had
used
ice
fo
cooli g
lo g
befo e
mode
ef ige atio .
I
a cie t
G eece,
ice
was
collected
f om
lakes
a d
ive s
a d
sto ed
i
buildi gs
i sulated
with
mate ials
such
as
sawdust.
Simila
methods
we e
used
i
Eu ope
a d
No th
Ame ica
u til
cooli g
machi es
became
commo
i
the
ea ly
20th
ce tu y.Japa
had
also
developed
seve al
fo ms
of
s ow
a d
ice
cooli g.
T aditio al
Himu os
a d
Yukimu os
used
sto e
o
woode
buildi gs
to
sto e
ice
o
s ow
alo gside
food
such
as
vegetables
a d
f uit.
A othe
Japa ese
method,
k ow
as
the
All
Ai
System,
cools
ai
th ough
di ect
co tact
with
s ow.
Othe
s ow
sto age
ideas
The
esea che s
also
looked
at
seaso al
s ow
sto age
studies
i
othe
places.
I
Ottawa,
Ca ada,
esea che s
exami ed
whethe
s ow
emoved
f om
st eets
a d
public
a eas
could
be
t a spo ted
to
a
la ge
s ow
deposit
a d
sto ed
fo
late
cooli g.O e
p oposed
deposit
had
a
volume
of
90,000
cubic
met es
a d
was
cove ed
with
a
eflective
a d
i sulati g
laye .
The
study
fou d
that
ci culati g
meltwate
was
the
most
effective
way
to
ext act
cold.A othe
possibility
was
sto i g
s ow
i
u de g ou d
ock
cave s.
Such
systems
could
be
built
i
u ba
a eas
a d
could
educe
the
dista ce
ove
which
s ow
would
eed
to
be
t a spo ted.The
study
also
oted
a
p oblem
with
s ow
collected
f om
cities.
U ba
s ow
ca
co tai
high
levels
of
polluta ts,
mea i g
the
meltwate
may
eed
to
be
co t olled
a d
t eated.
