Environmental Engineering Reference
In-Depth Information
Table 6.1
Limits for EPI for class C buildings as function of the climatic zone and of the ratio S/V
EPI
L
(kWh/m
2
)
Ratio S/V
(m
2
/m
3
)
Climatic zone
AB
C
D
E
F
B600
HDD
B601
HDD
B900
HDD
B901
HDD
B1,400
HDD
B1,401
HDD
B2,100
HDD
B2,101
HDD
B3,000
HDD
[3,000
HDD
B0.2
8.5
8.5
12.8
12.8
21.3
21.3
34
34
46.8
46.8
C0.9
36
36
48
48
68
68
88
88
116
116
The application of these standards is not easy and is beyond the scope of this
chapter, although an example of the application of the standards UNI TS 11300 to
a case study can be found in (Tronchin and Fabbri
2012
).
The above-recalled standards provide techniques for the calculation of the
specific energy use for heating and hot water production of a building. This spe-
cific energy is the ratio of total energy used over the total built-up area/volume.
This ratio is named Energy Performance Index (EPI) and is compared to a limit
numerical value EPIL, devised by the Italian Legislative Decree
311/06
.This
comparison allows determining the energy performance class of a building.
The values of EPIL are given by the Legislative decree
311/06
as a function of
the climatic zone in which the building is located, of the Heating Degree-Days
(HDD) defined by the norm ISO 15927-6 (
2007
) and of the ratio S/V, where S is
the total dispersion surface and V is the gross volume of the building.
These values are listed in Table
6.1
.
As both the EPI and the EPIL are known, the energy performance class is found
according to Table
6.2
.
6.3
Active Measures for Energy Efficiency: BAC Efficiency
Class in Residential Building
The European Standard EN 15232 defines the BAC efficiency classes. The stan-
dard presents two methods to evaluate the effects of building automation and
management functions on the energy performance of a building:
• the ''detailed method'', requiring a complete knowledge of the characteristic of
the building and of the installed lighting, and HVAC systems;
• the ''BAC Factors method'', allowing a quick but less accurate estimation of the
impact of the BACS and TBM systems on the energy performance of the
building in a reference period of 1 year.
Here, only the BAC Factors method is taken into consideration. According to
this method, the influence of BAC and TBM systems on the energy performance of
buildings is evaluated using two different numerical factors, called respectively
''BAC factor for thermal energy'' and ''BAC factor for electrical energy''. These
