Environmental Engineering Reference
In-Depth Information
As already mentioned, Sicily has also still active the Piano Casa, providing
volumetric prizes for demolition and rebuilding according to green building
techniques.
5.4.4
A Benchmark for the Elaboration of Performance Standards
to Improve the Current Regulatory Framework
From the analysis of the energy consumption in buildings of the Sicilian Region,
not surprising that the peak comes during the summer season in the hours of major
irradiation. Such data can be essentially connected to the climate features of Sicily
that comprises different climatic zones, but is characterized by very hot summers
all over the region.
Considering that in the national regulatory framework in Italy the energy effi-
ciency techniques are related to consumptions and comfort requirements during
the winter season, due to two different reasons. On one hand, the knowledge about
thermal modelling of buildings concerning hot climates is more difficult, on the
other, the European countries that are more attentive to environmental issues and
energy efficiency are in northern Europe.
Therefore, the measures to improve energy efficiency of buildings to be
included in the regional guidelines in Sicily have been defined based on a scientific
study elaborated by the eERG group of the polytechnic university of Milan (Italy)
within the project Passive-On.
15
The reference document is entitled Passivhaus for southern Europe -Guidelines
for the design (end use Efficiency Research Group, eERG
2007
) has revealed that
it is generally possible to limit without too much difficulty the thermal loads in
Southern Europe countries bringing the demand of net useful energy demand for
heating and cooling to 15 kWh/m
2
year, while the demand of primary total energy
(rooms heating, domestic electrical appliances, lighting and sanitary hot water) is
equal to 120 kWh/m
2
year. All this to keep a summer operational temperature
equal to 20 C in winter and below 26 C in summer.
What results from the analysis is that the cooling thermal loads can often be
covered with only passive measures (external insulation, solar screens, evaporative
cooling, etc.).
Even if the Italian Passivhaus inherits many of the concepts of the German
Passivhaus, the study has evidenced the need to modify some detail specifications.
In general the Italian mild climate allows reaching the comfort and the energy
limits of the Passivhaus standard using less constraining for what concerns:
• The insulation of opaque surfaces: while a typical German Passivhaus requires
25-35 cm of insulation external coating and 30-40 cm on the roof, in Milan
(latitude:4528
0
38
00
28 N; heating degree days: 2404; cooling degree days: 482;
15
Research and dissemination project within the SAVE Intelligent Energies program, developed
between 2005 and 2007, aiming at the promotion of passive houses in hot climates proposing to
analyze the way to extend the passivhaus design concept to Southern Europe.
