# Improving the Efficiency of Energy Consumption in Buildings: Simulation of Alternative EnPC Models
## 4 Application to a Case Study
### Photovoltaic Unit Installation  
In order to reduce its annual energy consumption, the school used three ESCOs to perform energy audits to the buildings, so that they could collect all the necessary data to present the possible energy-efficient solutions to reduce energy consumption (Table 4). Figure 4: Building A (**left**) and B (**right**) of Escola do Canigo. \begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Consumption December 2018–November 2019**} \\ \hline
**Month** & **Electricity Cost (EUR)** \\ \hline December & 2251.01 \\ \hline January & 3136.30 \\ \hline February & 2940.70 \\ \hline March & 2825.46 \\ \hline April & 2338.09 \\ \hline May & 3390.52 \\ \hline June & 2525.65 \\ \hline July & 1910.95 \\ \hline August & 1448.13 \\ \hline September & 2510.50 \\ \hline October & 3426.72 \\ \hline November & 2821.21 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Electricity consumption of the Canico School. On the basis of the data and solutions obtained, the intention is to discover, through this paper, which of the three types of EnPCs is the best for this type of public building. Given the observation that the highest consumption of electricity occurs between 7:30 a.m. and 7:00 p.m., it was found that there is potential for the installation of a photovoltaic panel system, because the time interval of higher energy consumption for the buildings coincides with the periods of higher production by the system. Given the fact that the installation would have to operate in different time periods, such as the school period on working days, the school period on non-working days (holidays), and weekends, AREAM defined that a necessary condition for the system not to produce more energy than that consumed would be to scale the photovoltaic solar system to the minimum output, which is about 6 kW. After data collection and analysis, AREAM studied energy, economic, and environmental viability for energy production for self-consumption. In calculating the investment, the costs of acquiring the equipment for the installation of photovoltaic solar energy systems were taken into consideration. These systems, according to the manufacturers, have a durability of 20 to 25 years, during which they regularly guarantee the desired values for the power supplied. After performing all feasibility studies, AREAM (a private, non-profit association, recognized as being of public utility, whose mission is based on the promotion of knowledge, innovation, and cooperation in the fields of energy and the environment) suggested the installation of a solar photovoltaic system for self-consumption, without batteries, with a nominal power of 6 kW, which would occupy a roof area of between 45-50 sq. m, out of a total of 500 sq. m available. Another possible solution was the installation of an identical system with a higher power (between 15 kW and 30 kW), with the prior knowledge that there could be a surplus of energy produced that would have to be sold to the grid in certain situations (school and non-school operating periods). In addition to the implementation of the photovoltaic system, AREAM also found that the cost of active energy could be reduced by installing more efficient equipment, such as LED lighting in classrooms and other spaces, and that the possibility of using solar thermal panels to reduce energy consumption for hot water should also be looked into. The adoption of the proposed solution allows for a reduction in the energy costs in terms of the electricity bill. Figure 5 shows the comparison between total electricity consumption between December 2018 and November 2019, and the estimated production of the photovoltaic system.