## 5 Results  
The hardware and software components of the IMBPC HVAC system were designed and implemented by researchers of the University of Algarve, in a partnership with the spin-off company EasySensing, Intelligent Systems (Faro, Portugal), and an HVAC installation and maintenance company, Rolear, Ltd. (Faro, Portugal). Having available the components, the IMBPC HVAC system was installed in building 7 of the Gambelas Campus of the University of Algarve, located in Faro, Portugal. Figure 24 shows an overview of the experimental setup used. As can be seen, the rooms under remote monitoring/control SPWS devices incorporated measuring the activity (movement), state of windows/doors, air temperature and relative humidity, and mean radiant temperature (walls temperature). An intelligent weather station provided the measurement and forecasts of the solar radiation and air temperature and relative humidity. The Mitsubishi Variable Refrigerant Flow (VRV) systems (PUHY-250 YMF-C external units and  
Figure 23: Displays and history. PEFY-P63 VMM internal units) are controlled and monitored by a TAC Vista BMS, which executes in a dedicated PC. The IoT platform, including the execution of the predictive models and the predictive control loop are executed in another PC, in our laboratory, located in a different building of the campus. Rolear technicians installed the IMBPC system in one week of work, starting on 14 May 2015. The intelligent weather station (see Figure 25) was installed on the terrace of the building, and the SPWS devices (see Figure 26) in adjacent Rooms 2.12, 2.11 and 2.13 of the building. As the rooms were nearby, no SPWS transmitter was need. Afterwards, the central node, the interface to the BMS and the IoT platform were installed. All systems were tested, making sure that all components had the correct behaviour. Data were acquired in the period between 14 May 2015 00:05:00 + 01:00 and 6 June 2015 12:00:00 + 01:00, corresponding to 23 days and 6768 samples). The atmospheric data were collected by the intelligent weather station, the room data were obtained using the SPWS devices, and the HVAC data were obtained using the BMS interface software. After the data acquisition period, the predictive models were designed. The experiments took place at the end of June, when the rooms were used for exams rather than for regular classes. Three adjacent rooms were employed. Room 2.12 was under IMBPC HVAC control, while Rooms 2.11 and 2.13 were under normal control. Rooms 2.12 and 2.13 have the same area, while Room 2.11 has an area double that of the others, possessing two air conditioners. Both experiments, which took place on different days, assumed two schedules, from 9 h to 13 h 5 m, and between 16 h to 18 h 5 m. Table 3 shows the energy (in kWh) spent in the three rooms, for the 4 occupation periods. In this table, the term _Priors_ denotes the time where the HVAC is operating before the start of all occupations (i.e., in the periods \(\left[ \begin{array}{cc}t_{op}&t_{oe}\end{array} \right]\)), in order to maintain thermal comfort within the scheduled occupation. The column labelled _Schedules_ denotes the energy spent for the four scheduled periods, and the last column denotes the total energy spent. Notice that in Tables 3 and 4 the values assigned for Room 2.11 are the sum of the corresponding values for each air conditioner. Figure 24: Overview of the experimental setup. TCP: Transmission Control Protocol; IP: Internet Protocol. Figure 26: (**a**) Programming one SPWS; (**b**) installing one SPWS. Figure 25: Installation of the intelligent weather station. As can be seen, due to the fact that the IMBPC tries to maintain thermal comfort during the occupation periods, more energy is spent by this approach. As we are considering four scheduled occupations, the energy spent in the prior periods is much larger than a unique, larger period, would - use. Note also that there is a significant savings of energy within the occupation periods. In terms of costs, as shown in Table 4, the situation changes.