Net ZEB Case Studies - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 474

showed that the true temperature of the office was closer to 26 °C. The
assumption was also made that the louvers would remain open during
winter, which is usually not the case.
These hypotheses should not have a large impact on the determination of
the different operational periods as the maximum air temperature of the
model in summer is close to the measured values. However, by looking at
the energy use for ceiling fans over three years, the real period of use can be
identified. As stated previously, the air-conditioning is almost never used in
thebuilding. Theperiod ofuseoftheair-conditioning defined during design
(January to mid-March) is therefore substituted by a period where ceiling
fans are used. It was found that the real period of use of the ceiling fans is
a little longer than the one predicted during design (the ceiling fans are still
used in early May).
These observations on ENERPOS demonstrate that several uncertainties
can appear during design and in the models. User behavior remains the
main challenge for the building performance simulations. In order to have
a better understanding of the user behavior, particularly with regard to
thermal comfort, a field study including a thermal comfort survey has been
conducted ontheoccupants ofENERPOS and ispresented in Section 7.5.12.
7.5.12 Thermal Comfort Experimental Study
7.5.12.1 Purpose and Methodology
An extensive field study has been conducted on the ENERPOS building in
order to investigate thermal comfort in an energy-efficient building under
tropical climate (Lenoir, 2013; Lenoir, Garde, and David, 2011). The
purpose was to compare physical measurements with thermal sensation
votes in the offices and the classrooms of the building and to compare these
results with different approaches, namely the comfort zones proposed by
Givoni that were used to assess thermal comfort during the design process
of the building.
The methodology followed for this experimental feedback was similar to
that of previous studies conducted on the thermal comfort of building
occupants (Hwang, Lin, and Kuo, 2006; Kwok and Chun, 2003). The
occupants of the building were asked to answer a thermal comfort survey,
developed by the PHASE laboratory at the University Paul Sabatier in
Toulouse (France), during the course of the ENERPOS research project