## 3 Use Case. CEDER-CIEMAT Microgrid
### Results
#### 3.5.1 Reducing Consumption of the Distribution Network  
Consumption from the distribution network can be reduced at any time of the day, in consecutive or alternate hours, depending on what is of most interest from the point of view of microgrid management.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**System** & **Performance (\%)** \\ \hline Lead-acid battery PEPA I & 83 \\ Lead-acid battery PEPA II & 80 \\ LFP Battery & 60 \\ Hydraulic system (Turbine/Pumps) & 32 \\ \hline \hline \end{tabular}
\end{table}
Table 7: Performance of generation sources and storage systems in the CEDER microgrid.  
From the point of view of this paper, consumption is reduced when it is above the CEDER average (40-60 kWh) and during hours with higher cost per kWh (higher pricing periods). These maximum pricing periods change from one month to the next, as shown in Figure 6. There are six different periods (P1, P2, P3, P4, P5, and P6) in the CEDER-CIEMAT tariff, and the price of each period is negotiated with the distribution company. Table 8 shows the Eur/kWh prices for each of these periods.  
The use case was carried out with data from 16 February 2023. So, the maximum charging periods are P1 (from 9:00 to 14:00 and 18:00 to 19:00) and P2 (from 8:00 to 9:00, 14:00 to 18:00, and 22:00 to 24:00). So, consumption will be reduced during those hours when it is above the CEDER average.  
Figure 7 shows the consumption data of the CEDER microgrid on 16 February 2023, without using the storage systems.  
There is above-average consumption between 8:00 (the start time of the working day at CEDER) and 15:00 (the end time of the working day at CEDER). Between 8:00 and 9:00  
Figure 6: Pricing periods according to CEDER’s electricity bill (Contract 6.1 TD).  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**P1** & **P2** & **P3** & **P4** & **P5** & **P6** \\ \hline
0.331692 € & 0.319483 € & 0.277395 € & 0.262635 € & 0.246811 € & 0.260134 € \\ \hline \hline \end{tabular}
\end{table}
Table 8: kWh prices (in euros €) for each period according to CEDER’s electricity bill (Contract 6.1 TD).  
Figure 7: CEDER microgrid consumption without using ESS (16 February 2023).  
and 14:00 and 15:00 correspond to the second most expensive pricing period (P2), and between 9:00 and 14:00 corresponds to the most expensive pricing period (P1).  
To reduce consumption, the ESSs are used according to their efficiency, i.e., first, the most efficient, then, the second most efficient, etc. According to step three of this methodology, to characterise the efficiency of the microgrid elements, the hierarchy of operation is as follows: Lead-acid battery PEPA I, Lead-acid battery PEPA II, LFP batteries, and Hydraulic system (Turbine/Pumps). The power generated by each of the storage systems to compensate for the power peak can be seen in Figure 8. The green line represents the total energy stored, which is the sum of the energy stored in PEPA I lead-acid battery (dark red line), the energy stored in PEPA II lead-acid battery (red line), the energy stored in the LFP battery (yellow line), plus the energy stored in the Pumping-Turbine system (blue line).  
Figure 9 shows the reduction of consumption using ESS, and there is a flatter consumption in the microgrid. The red line represents the consumption of the microgrid if energy stored systems were stopped, the yellow line represents the real consumption of the microgrid with energy storage systems working, and the green area is the energy saved due to the use of storage systems.  
Figure 9 also shows in green the energy savings obtained by reducing consumption in periods P1 (245.31 kWh) and P2 (43.07 kWh).  
Figure 8: Energy generated by ESS (16 February 2023).  
Figure 9: CEDER microgrid consumption using ESS (16 February 2023).