## 3 Results and Discussion
The only meters capable of measuring this value are the classic Zennio monitoring and automation tool, along with the Mk10A smart meter, as shown in Figure 12. This capability is one of the reasons the EDMI model is widely applied to the Greek distribution system as the main metering device [20,28]. Regarding accuracy, Zennio KES-Plus is more precise as a monitoring tool, but the variation is negligible at 12 kVAr after testing. Consequently, the EDMI module appears to have the best performance, as shown in Table 4.  
For the final step, the two main units applied in the Greek distribution systems are tested and directly compared and illustrated in Figure 13. As mentioned previously, the EDMI Mk10A has the best mean accuracy, and it is the most affordable and practical device to install as an energy meter; hence, it is widely adopted in energy metering applications. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**A/A**} & **Landis\&Gyr** & **EDMI** & **ELControl** & **ABB** & **Zennio** \\  & **MM2000** & **MK10A** & **Microvi93** & **DMTME** & **KES-Plus** \\ \hline
1 & N/A * & 0 & 0 & 0 & 0 \\
2 & N/A & 1.5 & 1.1 & 1 & 1 \\
3 & N/A & 3.2 & 2.8 & 2.7 & 4 \\ \hline
4 & N/A & 6.5 & 6.3 & 7.9 & 7 \\
5 & N/A & 9.7 & 9.2 & 11.2 & 9 \\ \hline
6 & N/A & 16.1 & 16.3 & 18.5 & 13 \\
7 & N/A & 17.9 & 18.1 & 24.4 & 17 \\
8 & N/A & 19.3 & 19.6 & 26.4 & 19 \\
9 & N/A & 19.4 & 19.8 & 27.1 & 20 \\ \hline
10 & N/A & 19.6 & 20.1 & 27.8 & 21 \\
11 & N/A & 20.1 & 20.7 & 30 & 23 \\
12 & N/A & 21.4 & 24 & 35.3 & 24 \\
13 & N/A & 22 & 24.8 & 36.4 & 25 \\
14 & N/A & 22.5 & 25.4 & 37 & 26 \\
15 & N/A & 23.5 & 27.3 & 40.3 & 27 \\
16 & N/A & 24.3 & 28.7 & 41.7 & 28 \\ \hline \hline \end{tabular}
* Values are not available as not measurable by the module  
\end{table} 
Table 3: Total positive reactive power consumption (Q+) in KVAr for the 4 modules. Figure 12: Reactive power (Q\(-\)) for the EDMI smart meter and the Zennio analyzer. As it can be seen, all values have a normal increasing trend, so testing was conducted as expected, without any faults. Even though a typical meter measures only the real power in a commercial building, reactive power caused by inductive or capacitive loads is sufficient and should be computed as well, since it causes voltage drops, excessive heat and power losses, as shown in Figure 14[20, 29]. Hence, the adoption of smart meters will let the supplier know the kind of power they provide, adjust pricing according to load forecasting[16] and, most importantly, prevent electricity theft. A smart meter can allow for an additional setting, now unavailable to most customers: the utilization of electric vehicles. As power management strategies can now be applied by the user even from a smartphone application, load demand is decreased; hence, the EV can be charged sufficiently, without power drops affecting the building energy requirements[13, 14, 15, 16, 17, 18, 19, 20]. When the consumer demands more power for home appliances, e.g., air-conditioning during peak hours, the smart meter reduces the power output of the EV charger to avoid overload, while still providing adequate energy, in a completely automated sequence. \begin{table}
\begin{tabular}{c c c c c c} \hline
**A/A** & **MM2000** &
\begin{tabular}{c} **EDMI** \\ **MK10A** \\ \end{tabular} & **Microup3** & **ABB** & **KES-Plus** \\ \hline
1 & N/A * & 0 & N/A & N/A & 0 \\
2 & N/A & 50 & N/A & N/A & 43 \\
3 & N/A & 144 & N/A & N/A & 139 \\ \hline
4 & N/A & 240 & N/A & N/A & 239 \\
5 & N/A & 327 & N/A & N/A & 326 \\ \hline
6 & N/A & 428 & N/A & N/A & 431 \\
7 & N/A & 504 & N/A & N/A & 510 \\
8 & N/A & 553 & N/A & N/A & 560 \\
9 & N/A & 581 & N/A & N/A & 585 \\ \hline
10 & N/A & 610 & N/A & N/A & 615 \\
11 & N/A & 656 & N/A & N/A & 660 \\
12 & N/A & 684 & N/A & N/A & 700 \\
13 & N/A & 720 & N/A & N/A & 730 \\
14 & N/A & 748 & N/A & N/A & 760 \\
15 & N/A & 777 & N/A & N/A & 790 \\
16 & N/A & 808 & N/A & N/A & 820 \\ \hline \end{tabular}  
* Values are not available for the 3 meters  
\end{table}