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ESTIMATION OF HEAT DEMAND IN BUILDINGS
HERENA TORIOPPRE, SS 10/11
OLDENBURG
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05.05.2011 SS 10/11 2
CONTENTS• INTRODUCTION
– ENERGY SITUATION IN BUILDING SECTOR
• PHYSICAL PRINCIPLES– HEAT TRANSFER– MOISTURE TRANSFER
• ENERGY BALANCES– STEADY STATE BEHAVIOR– DYNAMIC BEHAVIOR - THERMAL INERTIA
• CALCULATION METHODS– MONTHLY METHOD– SIMPLIFIED METHOD
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05.05.2011 SS 10/11 3
• ENERGY CONSUMPTION IN GERMANY
Energy consumption by sectors (Germany)
Households, 45%Transport, 28%
Industry, 27%
Source: VDEW-Materialien: Endenergieverbrauch in Deutschland, 2002
Space heating,
81%
Domestic hot water demand,
13%
Lighting, 5%
ENERGY SITUATIONINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 4
Others 8%Electricity 4%
Distric heating 7%
Carbon 2%
Gasoil 36%
Natural gas 43%
• FUELS USED IN GERMANY TO SUPPLY THE SPACE HEATINGDEMAND
Renewables are here!
Source: VDEW-Materialien: Endenergieverbrauch in Deutschland, 2002
ENERGY SITUATIONINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 5
IN GERMANY EnEV - “Energie-einsparverordnung”:– Limits the maximal energy demand for buildings according
to their constructive details– Establishes a calculation method for the energy demand of
a building -> basis for comparison– Defines different building “categories” according to their
energy consumption
ENERGY SITUATIONINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 6
ENERGY SITUATION
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 7
Heat demand:• Typical building: 80 – 300 kWh/m2a
• “Low Energy house” : 40 – 79 kWh/m2a
• “Three-liters house”: 16 – 39 kWh/m2a
• “Passive house”: max. 15 kWh/m2a
• “Zero-Energy house”: 0 kWh/m2a
ENERGY SITUATIONINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 8
ENERGY SITUATIONINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
– Approved July08 -> Jan 09
– Application to new buildings
RENEWABLE ENERGY HEAT STANDARD “EEWärmegesetz”:
• Biogas 30%• Solar: 15%, 0.03-0.04m2coll/m2living area • Others (biofuels, wood, geothermal or environmental heat) 50%
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ENERGY BALANCE IN A TYPICAL BUILDING
Transmission losses
Ventilation losses
Solar heat gains
Internal gains
Heat supplied by heating system
0%
20%
40%
60%
80%
100%
Cold bridges %Ventilation losses %Transmission losses %
Biggest energy saving potential!!!
GENERAL BALANCESINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 10
• BUILDING ENVELOPE: Heat losses can amount up to 75% of total heat losses
Roof 19%External walls
20%
Floor to crawl space 9%
Windows 52%
Percentage of heat losses through different constructive parts of the envelope
BASIC USED SOLUTION: Reduction of the major heat losses using better materials in the building envelope
Moving to energy efficient buildings…
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
GENERAL BALANCES
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• CONDUCTION
Tin
Tout
λmaterial [W/mK]
dmaterial [m]
[m2K/W]
∑= layerwall RRlayerl
layerlayer
dR
λ=
∑==
layer
layerwall
wall dRU
λ
11
[m2K/W]
[W/m2K]
)(, outinwallwallwallT TTAUQ −⋅⋅=
T
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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05.05.2011 SS 10/11 12
∑ ++==
elayer
layer
i
wallwall
hd
hR
U11
11
λ
[W/m2K]
Superficial heat transmission coefficient: [0 -100 W/m2K]
• Floor to unheated basement
• Roof in summer conditions• Roof under winter conditions!
T
TRANSMISSION LOSSES: Conduction + convection
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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Geometric thermal bridgeMaterial caused thermal bridge
Source: Maas
• DEFINITION: Places on the envelope where, during the heating period, higher heat flows and lower inner surface temperatures occur.
• CAUSES:
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFERTHERMAL BRIDGES
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05.05.2011 SS 10/11 14
Ψ = Coefficient of losses throughthermal bridge, [W/mK]
f = (superficial) Temperature factor , [-]
Θsi= surface temperature inside wall
Θe = exterior temperature
Θi = indoor temperature
f=0 -> exterior temperature
f=1 -> indoor air temperature
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFERTHERMAL BRIDGES• CHARACTERISATION:
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Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFERTHERMAL BRIDGES
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Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFERTHERMAL BRIDGES
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VENTILATION (CONVECTION) LOSSES
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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VENTILATION LOSSES• Definition: Energy losses due to the exchange of an air flow
between the building and the surroundings• Characterization: measured in h-1 = represents the portion of
the total (heated) building volume exchanged in one hour• Causes:
– Air leakages in the building envelope: constructive problem / solution
– Health and Safety reasons: necessary to allow pollutants leave the living space
According to building typology (residential, office buildings, hospitals…) minimum air exchange rates have to be assured
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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VENTILATION LOSSES
Source: Recknagel
Tight envelope (n50<3h-1)
Untight envelope (n50> 5h-1)
Regulable Ventilation units
Window open up without cross ventilation
Window open up with cross ventilation
Window open without cross ventilation
Window open with cross ventilation
Air exchange
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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05.05.2011 SS 10/11 20
VENTILATION LOSSES
TYPICAL VALUES for a non efficient old building: 1,5 – 2 h-1 or even higher (through air leakages in envelope)
According to EnEV (Energieeinsparverordnung) in Germany:
Mech.vent.: 0,4Air leakages: 0,2
Air leakages: 0,6Air leakages: 0,7Values allowed in EnEV, h-1
Efficient building with mechanical ventilation system
Efficient (proven tight) building without mechanical ventilation system
Non efficient building
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
HEAT TRANSFER
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• Transport mechanisms:– DIFFUSION– CONVECTION
(ventilation)– (SORPTION)
1 - 2 liters/day person
2 people house: ca. 2liters/day person
4 people house: ca. 4liters/day person
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFER
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Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFER
Air temperature
Max
imal
wat
erco
nten
tin
air
9.4g
10°C
7.9g
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INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
CARRIER (MOLIERE) DIAGRAM
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INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
CARRIER (MOLIERE) DIAGRAM1.- 100%RH, 20°C,14.5g/kg
2.- 100%RH, 10°C,7.5g/kg
3.- 70%RH, 20°C, 7g/kg
4.- 85%RH,17°C, 7g/kg
Air density ≈ 1.2kg/m3
Dew point temperature
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Source: Maas
Air temperature
Rel. humidity
Dew
poin
t tem
pera
ture
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFER
Air temperature
Rel. humidity
Dew
poin
t tem
pera
ture
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INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERSUPERFICIAL TEMPERATURETHERMAL BRIDGES
External wall - corner
Indoor air temp. 20°C
70%RH
SurfacetemperaturesMax. relative humidity
Outdoor air temp. -15°C
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INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERMOLD GROWTH
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05.05.2011 SS 10/11 28
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFER
Relative humidity, %
Pro
babi
lity
of g
row
th
Surf. temperature, °C
Pro
babi
lity
of g
row
th
HUMIDITY TEMPERATURE
MOLD GROWTH
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05.05.2011 SS 10/11 29
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERWATER CONDENSATION
MOLD GROWTH
Rel. Humidity
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05.05.2011 SS 10/11 30
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFEREXAMPLEMold growth is more restrictive condition Rel.
Humidity
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05.05.2011 SS 10/11 31
Source: Maas
Description DescriptionDescription Unit Unit
Temperature
Heat conductivity
Thermal resistance
Heat flow
Heat transm. Coeff.
Partial vapor pressure
Material transm. Coeff.
Vapor diffusivity
Resistance to vapor diffusion
Vapor diffussion flow
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERDIFFUSION
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Air
Insulation
Concrete
Metal
Bitumen
Source: Maas
material
air
material
material
air
air
material
aird
d
ZZ
δδ
δ
δμ ===
[-]dmaterial=dair
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERDIFFUSION
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05.05.2011 SS 10/11 33
Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFER
40 (50/400)Wood
Tight(100000000)
Alu-foil
5-1030-100
InsulationKorkPU foams
70-150Concrete
μMaterial
DIFFUSION - EXAMPLE
1086
472281
g
g = 0.421 g/m2h
[m h Pa / kg]
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Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERCONVECTION - EXAMPLE
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Source: Maas
Ps = 1170 Pa
R = 462 J/kgK
Ps = 139 Pa
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERCONVECTION - EXAMPLE
Vh,buil=50m3 ; n=0.8 h-1
Vvent=40m3/h (=Vh,buil*n)
Ti=20°C, RH=50%
Te=-10°C, RH=80%
-10°C 1.15
1.15 263.15304.3
and
and
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Source: Maas
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERCOMPARISONCONVECTION - DIFFUSION
g
Aint,walls=22.5 m2
n = 0.8 h-1
Outside: 80% RH, -10°C
Inside: 50% RH, 20°C
g = 0.421 g/m2h
9.47 g/h304.3 g/h
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Source: Maas
Humidity production
Req
uire
dai
r exc
hang
eRel. humidity
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
MOISTURE TRANSFERCONVECTION:Air exchange
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Qv
In order to keep
the room temperature
at a constant acceptable value
Energy Supplied = Heat Losses - Energy Gains
STEADY STATE
Transmission losses
Ventilation losses
Solar heat gains
Internal gains
Heat supplied by heating system
“Passive gains”“Active gains”
QT
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
ENERGY BALANCES
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TRANSMISSION LOSSES
– INCLUDING THERMAL BRIDGES
– TOTAL TRANSMISSION LOSSES
)(,,, outinienvienvenvT TTAUQ −⋅⋅Σ=
)()( ,,, outinenvtbienvienvbuilT TTAUAUQ −⋅⋅Δ+⋅Σ=
envelopetbienvienvbuildingT AUAUH ⋅Δ+⋅Σ= ,,, [W/K]
[W]
[W]
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL LOSSESenv,i = walls, floor, roof,
windows
(separately for each of them)
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nVH builhV ⋅⋅= 34.0,
)( outinVV TTHQ −⋅=
VENTILATION LOSSES
76.0, ⋅= bruttobuilh VV
Heat capacity of air [Wh/m3K]
[W/K]
HEATED volume of the building [m3]
According to the German regulation EnEV, can be simplified:
n = air exchange rate [h-1]
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL LOSSES
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TOTAL LOSSES (TRANSMISSION+VENTILATION)
– Transmission Losses
– Ventilation Losses
– Total Losses
)()()( ,,, outinToutinenvtbienvienvbuilT TTHTTAUAUQ −⋅=−⋅⋅Δ+⋅Σ=
)( outinVV TTHQ −⋅=
)()( outinVTlosses TTHHQ −⋅+=
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL LOSSES
[W]
[W]
[W]
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WINDOWS– Upane = 3 – 0.6 [W/m2K]
-> great influence on heat demand
– SHGC, g = 0.5 – 0.8 [-]-> great influence on
cooling demand
– ε = 0.84– εlow = 0.2 !!!
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL LOSSES + GAINS
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05.05.2011 SS 10/11 43
Qv
Energy Supplied = Heat Losses - Energy Gains +- Energy Stored
ENERGY BALANCE - DYNAMIC BEHAVIOR
Transmission losses
Ventilation losses
Solar heat gains
Internal gains
Heat supplied by heating system
QT
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
ENERGY - DYNAMIC
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0
500
1000
1500
2000
2500
3000
Woo
d
Gla
ss
Min
eral
insu
latio
n
Foam
gla
ss
San
d
Bric
k
Alu
min
ium
Con
cret
e
Wat
er
rho
[kg/
m3]
0
1000
2000
3000
4000
5000
Woo
d
Gla
ss
Min
eral
insu
latio
n
Foam
gla
ss
Sand
Bric
k
Alum
iniu
m
Con
cret
e
Wat
er
c [J
/kgK
]
Specific heat capacity
density
Source: Wikipedia
iiiisto dAcC ⋅⋅⋅= ρ
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
ENERGY - DYNAMICTHERMAL MASS
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0
1
2
3
4
5
Woo
d
Gla
ss
Min
eral
insu
latio
n
Foam
gla
ss
San
d
Bric
k
Alu
min
ium
Con
cret
e
Wat
er
lam
bda
[W/m
K]
Source: Wikipedia
THERMAL MASS
0
500
1000
1500
2000
2500
3000
Woo
d
Gla
ss
Min
eral
insu
latio
n
Foam
gla
ss
San
d
Bric
k
Alu
min
ium
Con
cret
e
Wat
er
rho
[kg/
m3]
0
1000
2000
3000
4000
5000
Woo
d
Gla
ss
Min
eral
insu
latio
n
Foam
gla
ss
Sand
Bric
k
Alum
iniu
m
Con
cret
e
Wat
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c [J
/kgK
]
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL MASS237
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05.05.2011 SS 10/11 46
Tem
pera
ture
Thickness
Concrete Insulation
Source: Maas
Tem
pera
ture
Specific heat capacity
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
ENERGY - DYNAMICTHERMAL MASS
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05.05.2011 SS 10/11 47
Sola
r rad
iatio
nO
utdo
orTe
mpe
ratu
re
Source: Maas
U-Value[W/m2K]
Mass[kg/m2]
Out
door
Tem
pera
ture
Ene
rgy
flow
Time of day
Specific heat capacity
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
ENERGY - DYNAMICTHERMAL MASS
Sola
r ra
diat
ion
6cm
40cm
43.5cm
26cm
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05.05.2011 SS 10/11 48
TOTAL LOSSES (TRANSMISSION+VENTILATION)
– Transmission Losses
– Ventilation Losses
– Total Losses
)()()( ,,, outinToutinenvtbienvienvbuilT TTHTTAUAUQ −⋅=−⋅⋅Δ+⋅Σ=
)( outinVV TTHQ −⋅=
)()( outinVTlosses TTHHQ −⋅+=
Tin is the indoor desired temperature: regarded as a CONSTANT value,typically set between 19 and 21°C for the heating period.
For which time-step do we apply this
equation?
Depends on the data we have for the
outdoor temperature…
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[W]
[W]
[W]
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05.05.2011 SS 10/11 49
TOTAL LOSSES
• Tout represents MONTHLY mean values• tM represents the number of days of the month considered
24)()( ⋅⋅−⋅+Σ= MoutinVTmonthstTTHHQ
losses
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
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05.05.2011 SS 10/11 50
• gi represents the energy transmissivity of the window glass; typically is around 0.6
• FF represents the % of glass against frame in the window area; typically is around 0.7
• Fs represents the % of shadowing over the glass• Gwindow represents the incident solar radiation onto the
window, in Wh/m2
windowsFiwindowsmonthswindowsSolar GFFgAQ ⋅⋅⋅⋅Σ=,
SOLAR HEAT GAINS
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
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WINDOWS, 52% of total losses:1. Avoid heat losses -> Better insulation materials:
- Uw= 3 - 0.6 W/m2K
2. Increase solar heat gains -> Orientation- Highest solar irradiation on the south façade,
high potential for solar heat gains -> maximize glazed surface facing south
- North façade receives very few solar irradiation, low potential for solar gains and high heat losses through windows -> minimize glazed surfaces
Single or two pane window
Three pane window filled with Ar/Kr
Yearly variation of solar path in the sky
Does not require much more planning effort. Typ. In efficient houses
Requires integral planning of the building integrated into its environmentTyp. Approach passive houses
INTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
THERMAL LOSSES + GAINS
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• Internal heat gains depend on the use pattern of the building: office, hospital, residential…
• For residential buildings: constant hourly value of 5 W/m2, per m2
useful area in the building
MtAQ Nmonthsgains ⋅⋅⋅Σ= 245int_
INTERNAL HEAT GAINS
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
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05.05.2011 SS 10/11 53
– Simplification:
– Actually, not all energy gains can be “used”:
• η depends on the heat storage capacity of the building structureand its materials, which is a function of ρ [kg/m3], c [Wh/kgK], d [m], A [m2] of the material:
gainswindowsSolarlossesh QQQQ int_, −−=
)( int_, gainswindowsSolarlossesh QQQQ +−= η
iiiisto dAcC ⋅⋅⋅= ρ
ENERGY DEMAND
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
[Wh/a]
[W/K]
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– Types of building constructions according to its heat capacity
• LIGHT– Csto/A < 50 Wh/m2K
• HEAVY– Csto/A > 130 Wh/m2K
– η = 0.9 for light buildings– η = 0.95 for heavy buildings
)( int_, gainswindowsSolarlossesh QQQQ +−= η
ENERGY DEMAND
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
[-]
[-]
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– BUILDING WITH ZONES AT DIFFERENT TEMPERATURES:
• German Norm: gives correction factors, Fx, that have to be applied to obtain the HT corrected of the building
0.6- Floor to ground- Walls and floor to unheated crawl
space
0.5Walls and roofs to unheated rooms
1Outside wall, window, roof, floor
Fx [-]Building part
envelopetbwallwallT AUAUH ⋅Δ+⋅Σ=
envelopetbxwallwallT AUFAUH ⋅Δ+⋅⋅Σ=
ENERGY DEMAND
MONTHLY METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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• Tout represents mean DAILY values• Sets up a “heating limit” (15°C), above which no space heating is
required. For this conditions (Tin-Tout)=0• Below the “heating limit”, (Tin-Tout) is calculated and added up to
give a value of the “degrees-day”
∑ −=z
outint TTG1
15/20 )(
TOTAL HEATING DEMANDDEGREE-DAYS
DEGREE-DAYS METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Kd/a]
[°Cd/a]
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TOTAL HEATING DEMAND
)( int, ernalwindowssolarlossesh QQQQ −−= η
tVTdayslosses GHHQ ⋅+Σ= )( MoutinVTmonthstTTHHQ
losses⋅−⋅+Σ= )()(
windowsFiwindowsmonthswindowsSolar GFFgAQ ⋅⋅⋅⋅Σ=,
)( int ernalsolarhlosses QQQQ −−= η
windowsFiwindowsnorientatiowindowsSolar GFFgAQ ⋅⋅⋅⋅Σ=,
Ngains AQ ⋅= 22int_MtAQ Nmonthsgains ⋅⋅⋅Σ= 245int_
DEGREE-DAYS METHODINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
[Wh/a]
[Wh/a]
[kWh/a]
[Wh/a]
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– The equations for steady state conditions are not valid here!!!-> Energy stored in the building structure plays a role
– FREEware available (Hourly simulations):DOE2, eQUEST, ePLUS (http://www.doe2.com/ )
Much more accurate results
×Require the description of the HVAC system as INPUT×Time demanding to learn how to work with them: weather
data for Stüdl Hütte, etc… may not be in database
DYNAMIC TOOLSINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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• STATIC (simplified) METHODS & SOFTWARE: – Based on the steady-state simple equation -> quite simple
calculations
Depends only on (rough) CLIMATIC data and the BUILDING ENVELOPE -> Does not require the description of the HVAC system as INPUT
×Much more rough results
– Examples: “DEGREE-DAY Method” and Monthly simplified method in EnEV http://www.uni-
kassel.de/fb6/bpy/de/index.html
STATIONARY METHODSINTRODUCTION PHYS. PPLES. ENERGY BALANCES CALC. METHODS
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05.05.2011 SS 10/11 60
THANK YOU FOR YOUR ATTENTION!!!THANKS FOR YOUR
ATTENTION!!!!!!
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EXAMPLE• AN = 147m2 ; Vbrutto = 580 m3
• Awalls = 209.34 m2; Afloor = 88.2 m2; Aroof = 88.2 m2
• Awindows: S 15 m2; E/W 10m2; N 5.5 m2
• Uwalls = 0.45 W/m2K (walls); Ufloor-roof = 0.3 W/m2K (floor and roof); Uwindows = 1.4 W/m2K (windows)
• Utb = 0.1 W/m2K• n =0.6 h-1
• Windows: Ff= 0.7; Fs=0.9;g=0.58; • Heavy building
T 19°C
Orientation Solar radiation
[j] [kWh/m²]Nord 136
Süd 349
Ost 220
West 220
• G19/10 = 2750 °Cd/a (Hamburg)
10m
7.35m
3.0m
3.0m