Z E M C H 2 0 1 2 I n t e r n a t i o n a l C o n f e r e n c e
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•
the buildings are recalculated with enough PV to meet the Minergie-A balance
•
the buildings are recalculated with enough PV to meet the Net ZEB balance
Table 2: Used primary energy factors
[MB2031 2009], [EnDK 2009].
SIA Merkblatt 2031
(non-renewable
primary energy)
Swiss national
factors
(primary energy)
f
EPnren
[-]
f
CH
[-]
CH-electricity, user mix
2.52
2.0
pellet
0.21
0.7
wood
0.05
0.7
district heating
0.79
0.6
Minergie-A does not include the operational energy for plug loads and lighting. Therefore,
plug loads and lighting are considered with an across-the-board value of 42.8
kWh
EPnren
/(m
2
a) for Net ZEBs. The size of the photovoltaic system is adapted to cover
both the demand for plug loads and lighting. This, of course, results in a higher value of
embodied energy for Net ZEBs.
Figure 5 shows the deviation of the operational energy and embodied energy in an
overall assessment for different building types. The upper pie charts show the
operational and embodied energy for the Minergie-A building with and without plug-loads
and lighting. The embodied energy share is between half and two thirds of the total
energy demand (figure 5, top left pie chart). Adding the operational energy for plug-loads
and lighting shifts the share to one third embodied energy and one third for plug-loads
and lighting and one third for thermal comfort systems (figure 5, top right pie chart). In
the case of Net ZEBs, the additional area of photovoltaic panels necessary to cover the
operational energy for plug-loads and lighting is considered in the calculation of
embodied energy. Net ZEBs shows only a slight change in the share of total energy
compared with Minergie-A including plug-loads and lighting (figure 5, bottom pie chart).
This comparison shows that the operational energy for plug-loads and lighting has a
major impact not only on the shares of the total energy demand, but also on the absolute
total energy demand. The total demand of Minergie-A buildings increases about 50%
when plug-loads and lighting are considered and by about 70% for Net ZEBs.
