## 3 Results and Discussion
Building B2 has been equipped with a VRF system. Considering the specific heating demand and the efficiency of the systems in Buildings B1 and B2, the specific energy consumed in each building is determined. With these values, applying the conversion factors of the Spanish Government, the specific primary energy \(\left(e_{\text{P}}^{RCZ}\right)\) and the emissions associated \(\left(gg_{H}^{RCZ}\right)\) with Buildings B1 and B2 are determined. In the case of Building B2, since it is a heat pump, the contribution of renewable energy \(\left(e_{\text{RE}}^{RCZ}\right)\) can be determined according to Equation (3). The results are presented in Table 13.  
Regarding primary energy consumption and emissions, the results obtained (Figure 7) indicate that in all cases, the primary energy consumed by the VRF system installed in Building B2 is lower than that consumed by the LTCB system installed in Building B1 throughout all heating months. Additionally, the emissions from the Building B1 system are higher than those from the Building B2 system. By analyzing actual energy consumption, building activity, and outdoor climatic conditions during specific periods, alongside the characteristics of the facilities and their operational parameters, an assessment has been conducted regarding (i) the energy efficiency of the systems, (ii) primary energy consumption, and (iii) emissions during the heating season of a University Center situated in a warm climate zone of Europe. The key findings are summarized below. This study provides a comprehensive assessment of Variable Refrigerant Flow (VRF) systems employed in a university building during winter, presenting a critical comparison with traditional HVAC technologies, such as natural gas-fueled boiler systems. The research reveals an impressive seasonal energy efficiency value of 5.349 for the VRF system, indicating substantial energy savings and significantly reduced environmental impacts. Specifically, the findings demonstrate a 67% reduction in primary energy consumption and a 79% decrease in greenhouse gas emissions per square meter, highlighting the effectiveness of VRF systems in meeting high winter heating demands, particularly in regions with continental climates, according to Spanish Primary Energy Factors (PEFs). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Month**} & \multicolumn{2}{c}{**B1**} & \multicolumn{2}{c}{**B2**} \\  & \(\mathbf{e_{\text{P}}^{RCZ}}\) & \(\mathbf{gg_{\text{SH}}^{RCZ}}\) & \(\mathbf{e_{\text{P}}^{RCZ}}\) & \(\mathbf{gg_{\text{SH}}^{RCZ}}\) & \(\mathbf{e_{\text{RE}}^{RCZ}}\) \\  & **(kWh/m2)** & **(kg/m2)** & **(kWh/m2)** & **(kg/m2)** & **(kWh/m2)** \\ \hline January & 50.56 & 10.65 & 21.11 & 2.91 & 31.33 \\ February & 45.88 & 9.66 & 19.77 & 2.72 & 28.16 \\ March & 42.75 & 9.00 & 16.63 & 2.29 & 26.96 \\ April & 29.07 & 6.12 & 7.35 & 1.01 & 20.03 \\ May & - & - & - & - & - \\ June & - & - & - & - & - \\ July & - & - & - & - & - \\ August & - & - & - & - & - \\ September & - & - & - & - & - \\ October & 4.37 & 0.91 & 0.58 & 0.08 & 3.13 \\ November & 38.47 & 8.10 & 12.67 & 1.75 & 25.20 \\ December & 27.06 & 5.70 & 9.11 & 1.26 & 17.66 \\ \hline \hline \end{tabular}
\end{table} 
Table 13: Summary of primary energy, emissions, and renewable energy of RE buildings.