Civil Engineering Reference
In-Depth Information
Energy Performance of Buildings:
A Comparison of Standard Assessment
Methods
R. Pernetti, L. Magnani and A. Magrini
Abstract Regarding energy performance assessment of existing building, the
European Standards EN ISO 13790 and EN 15316, adopted at national level in
Italy by Technical Standards UNI/TS 11300 (part 1 and 2), allow different
approaches and simplification levels for defining some representative input
parameters determining uncertainties in the results. Therefore, the reliability of
calculated energy performance could be affected. The analysis has been supported
applying a set of refurbishment actions on some representative cases of common
national residential building stock, comparing the energy performance obtained
with different calculation methods allowed by National Technical Standards and
laws. The results show how these differences can lead to uncertainties about the
class definition.
Nomenclature
Internal floor area of the conditioned space [m
2
]
A
f
b
tr,x
Temperature correction factor [-]
Global energy performance index (EP
H
? EP
w
) [kWh/(m
2
EP
gl
year)]
Energy performance index in the heating season [kWh/(m
2
EP
H
year)]
EP
H, env
Energy
performance
index
in
the
heating
season
for
building
envelope [kWh/(m
2
year)]
EP
H, L(2010)
Energy performance index target for the new construction from
2010
EP
w
Energy performance index for domestic hot water production [kWh/
(m
2
year)]
Q
l,e
Emission subsystem thermal losses [MJ]
Q
H,gn
Total heat gains for the heating mode [MJ]
Q
H, ht
Total heat transfer for the heating mode [MJ]
Q
H, nd
Building energy need for continuous heating [MJ]
