# Smart Waste Collection System with Low Consumption LoRaWAN Nodes and Route Optimization
## 5 Conclusions and Future Works  
The case study described in this work for waste collection in the region of Salamanca shows the improvement provided by the proposed system compared to a classic static collection approach. This system offers a better operation in terms of covered distance, fuel consumption, truck use and emissions, operating costs savings and collection of useful data for further waste generation analysis. In regard to the developed sensor, it features a low consumption rate and sufficient autonomy to work throughout the presented case. The sensor correctly obtains data and sends them without penalizing the autonomy due to the employed radio technology. Deploying this sensor allows the monitoring of implemented containers as well as the procurement of information about the waste production of inhabitants in each town. This helps the waste collection company detect whether more containers need to be deployed when the container filling is too fast at specific times of year, for example, when the population temporally grows during the summer. Regarding the coverage study, nine antennas in Salamanca region met the coverage requirements of the presented case study. This meant a reduced investment considering the covered extent of the land and the needed infrastructure in the region. Concerning the route optimization results, the simulation offered mean savings in distance of 28% in the analyzed case. Due to these savings, the time and use of trucks are also decreased, and consequently, the workforce costs decreased. Finally, the simulation process of collecting paper and board waste along with obtained data showed that collecting waste every 2 weeks does not suit the waste production of every town in the community. The collection capacity is sometimes insufficient and in other cases the opposite. Selecting the indicated collection frequency is fundamental for saving time when performing this task. This is the reason why a system that dynamically generates routes with updated information provides a decision-making tool to perform collections with the proper frequency (when they are really needed). In conclusion, as indicated by the case study, the proposed system includes a developed node which can operate efficiently for more than a year, obtaining useful data like weight, temperature and volume due to the low battery consumption. In addition, the coverage study showed that with a  
Figure 12: Savings results for each day of collection. reduced investment, a deployment in the region with a small number of antennas covering the whole province of Salamanca is feasible. Together with these results, the optimization system results provide savings in cost, time and workforce against a static collection route approach. The potential savings of totally deploying the waste collection system and the advantages of this kind of WSN could allow investment in the required infrastructure as well as enabling future IoT projects in the region, improving its technological development. Future strands of work include the use of the sensor with the current waste collection company and the use of more data related to the waste collection which is provided by this company. [PERSON] and [PERSON] conceived and designed the smart waste collection platform system while [PERSON] and [PERSON] contributed to the development and implementation of the sensor and the network employed in the system; [PERSON] developed the software and the optimization subsystem and wrote the paper. [PERSON] reviewed and supervised the whole work and shared his expertise in the field. [PERSON] is supported by a pre-doctoral fellowship from the University of Salamanca and Banco Santander. This work was supported by project MOVIURBAN: Maquina social para la gestion sostenible de ciudades inteligenes: movilidad urbana, datos abierto, sensores moviles SA70U16. The project MOVIURBAN was co-financed with Junta Castilla y Leon funds.