# Exploring the Feasibility of Autonomous Lighting Systems for Pedestrian Crossings in Off-Grid Areas
## 4 Discussion  
In the authors opinion, only a holistic and comprehensive approach to an energy analysis can answer the question of proper operation in a specific location. Table 7 summarizes the results obtained for the correct operating time of the autonomous lighting system. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Scenario** & **Range of Days in a Year** & **Number of Days in a Year of** \\
**Number** & **of Correct Operation** & **Correct Operation** \\ \hline
1 & 97 \(\div\) 243 & 146 (40.0\%) \\ \hline
2 & 95 \(\div\) 267 & 172 (47.1\%) \\ \hline
3 & 48 \(\div\) 305 & 257 (70.4\%) \\ \hline
4 & 34 \(\div\) 347 & 313 (85.7\%) \\ \hline
5 & 1 \(\div\) 365 & All year (100\%) \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Summary of simulation results for the correct operating time of a stand-alone lighting installation. Figure 32: Selected results for the full calendar year. During summer, when solar radiation is available, batteries are charged at the level SOC = 97-100%. Therefore, it can be assumed that the energy storage bank is not operating in a daily deep discharge cycle. The impossibility of meeting the lighting levels throughout the year should be a counterindication to the use of solutions based on photovoltaic installations at pedestrian crossings outside built-up areas. The existence of the installation may contribute to a misunderstanding of the lighting situation by drivers and pedestrians. Users may be under the impression that the lighting consideration used achieves the intended technical parameters. As presented in this article during the month of December, this is problematic and may contribute to impairing the driver's ability to recognize the pedestrian, leading to a conflict or accident. The most critical component of the installation is the battery. During periods of reduced solar radiation availability, the battery charge level decreases when maintaining the required minimum SOC of 50%. It can be noticed that with such a cycle, it will operate at a minimum of 5 years, and with a good perspective even more; unfortunately, it is difficult to determine exactly what the period is. It is worth mentioning that the operation of lead-carbon batteries is specified by the manufacturer to be approximately 15 years. However, this applies to favorable operating conditions, such as positive operating temperatures. So, there will certainly be a shorter period of time. It should be mentioned that the PV installation energy production data used in the analysis was appropriately illuminated by sun, and there were no trees that were growing in the area to cause shade on the PV panels. This is quite an important issue, as it requires the lighting systems to be installed in the same way. The reliability analysis of pedestrian crossing lighting powered by photovoltaic panels includes an assessment of various technical, environmental, and economic factors that may affect the operation and performance of the lighting system. Below is presented a summary of factors that should be taken into consideration in the design process of an autonomous lighting system:  
* **Energy efficiency of the PV panels. ** Analysis of the performance of PV panels is crucial to assess their ability to generate required electric energy for the LEDs. * **Weather conditions. ** Local weather conditions, such as sunshine, rainfall, snow, fog, and the variability of weather conditions throughout the year, can affect the availability of the energy from PV panels. * **System durability**: System components, such as photovoltaic panels, batteries, charge controllers, etc., must be durable and resistant to weather and other external conditions. * **Energy consumption**. An accurate assessment of the energy consumption of a lighting system under different conditions, such as day and night, time of year, and pedestrian traffic in a given location, is important to determine the overall power requirements of the system. * **Safety. ** Proper illumination of pedestrian crossings is crucial for road safety.