Net ZEB Case Studies - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 405

minimum fluid flow for every loop, lighting and electrical appliances gains,
efficiencies of system components, deadbands and setpoints for heating/
cooling systems, thermo-physical properties of the envelope, and so on.
Figure 7.45 shows some examples of the sensitivity analysis results
obtained.
Fig. 7.45 Sensitivity analysis of GHP electricity consumption for heating
on (a) PID setup temperatures, (b) infiltration, and (c) tank setpoint
temperature
7.3.9 Conclusions and Lessons Learned
This section described an Italian case study of a net-zero energy house - the
Leaf House. A thermo-physical model of the LH was created in the TRNSYS
environment. Due to the fact that the active plant of the LH is particularly
complex, some assumptions were made to simplify the description of the
model (e.g., some recirculating nodes were not considered). During the
implementation of the model some limits of the tool in the description of
the real environment were observed. Nevertheless, the obtained calibrated
model is very reliable considering the results of the comparison between
monitored and simulated data. For strengthening the obtained results, an
SA on the main important parameters of the model was carried out; it
permitted observing parameters that play a major role in variations of
outputs. According to this experience we believe that the development of
a sensitivity analysis is an important step for obtaining a reliable model
and calibrating it. Attention must be paid to the selection of gains (e.g.,
occupation levels, lighting, and appliances) and other user-defined