STIEBEL ELTRON Heat pumps, Technical Manual

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EnErgy SavIngS ordEr EnEv [gErmany]
Energy Savings Order
the eU energy Performance of
buildings Directive obliged Member
states to translate measures regarding
energy and Co
2
reductions by
2006 into their national laws. the
eneV 2002/2004 already laid down
requirements for new buildings and
introduced the energy performance
certificate. Adhering to the required
limits meets the energy-technical
requirements for new residential
properties to obtain planning
permission [in Germany]. the
eneV 2007 introduces the energy
performance certificate for existing
residential buildings as well as for
non-residential buildings. the energy
performance certificate details the
energy-technical quality of a building
and retains its validity for ten years.
EnEV for residential properties
Calculation of the primary energy
demand Q
P
energy requirements made of
residential buildings and the system
technology employed are considered in
unison. this global approach enables
an overall statement appertaining
the building envelope and the
system technology to be established
and is based on the primary energy
which allows losses during energy
generation and transmission to be
taken into consideration. to calculate
the annual primary energy demand Q
P
and the system expenditure of energy
value e
P
, the annual heat demand
Q
h
of the building and the available
surface area A
n
must be known. the
system expenditure of energy value
e
P
, which has no dimension and
which relates to the primary energy
for heating, ventilation and DHw,
enables the assessment of the entire
system technology. Furthermore,
this parameter forms the basis for
calculating the annual primary energy
demand Q
P
of a building, and describes
the system efficiency. the lower the
system expenditure of energy value,
the greater the scope for the building
envelope, i.e. the physical building
characteristics. this highlights the
importance of the cooperation between
all engineers and all those involved in
the process.
Calculation of the primary energy demand
Effects of standards
Optional compensations between the building and the system
total energy demand
energy efficient version
energy inefficient version
ratio external surface area / volume (1/m)
Q
p,m
ax
= per
mi
ssible annu
al ener
gy
dem
and (k
w
h/
(m² p
.a
.)) r
el
ati
ve to t
he ar
ea of a
vail
able sp
ac
e
energy savings
calculation
system engineering
calculations
Calculating the structural
physical parameters
Max. annual energy demand
Annual heat demand
system expenditure of energy value
Primary energy
demand
Heating energy
demand
DHw
demand
system expenditure
of energy value
* (Q
tw
fixed value 12.5 kwh/m² p.a. acc. to eneV)
Q
P
= ( Q
h
+ Q
tw
* ) x e
P
( )
= + x
building
system