# Thermoelectric Generator-Powered Long-Range Wireless Real-Time Steam Leak Detection in Steam Traps
## 6 Conclusions  
This paper presented a novel Internet of Things (IoT) device tailored for Industry 4.0 applications. The key innovation of this device is its battery-less and heat-powered design, addressing the challenges associated with using lithium batteries in high-temperature and explosive industrial environments. As such, this sensor is a promising candidate for effective process monitoring in these demanding conditions. We demonstrated the device's advantages over existing technologies, including autonomy, maintenance-free operation, edge computing capabilities, high data transmission rates, and minimal intrusiveness. In the context of detecting steam leaks in steam traps, a major challenge lies in selecting the appropriate leak detection method. Relying solely on temperature measurements is insufficient in some scenarios, particularly as temperature data may not always be available in on-site operations. Therefore, additional parameters, such as ultrasonic measurements, are essential for improving system accuracy. Ultrasound technology allows for the differentiation between liquid and steam, as steam generates a high-frequency hissing sound, whereas liquid does not. Additionally, it enables easy detection of blocked valves due to \begin{table}
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**Manufacturer** & **Product** & **Main Tech** & **Key Features** & **Target Industry** & **Comm. Protocol** \\ \hline Spirax Sarco & STAPS & Ultrasound and temperature & - & Real-time wireless monitoring, - & General industry (petrochemical, compatible with ATEX. & WirelessHART \\ \hline Gestra [18] & SPECTORcompact & Conductivity & Different conductivity of the pipe with steam. & Industrial processes with high steam demand. & RS485/Modbus \\ \hline Armstrong International [19] & SteamEye & Ultrasound and temperature & - & Non-contact system. Simple and fast installation. & Manufacturing, power generation, healthcare. & Proprietary RF (radiofrequency) \\ \hline Henkel (Loctite) & Pulse Smart Steam Trap & Temperature & - & Continuous analysis via app. & Chemical, oil and gas, industrial plants. & BLE \\ \hline AEInnova (this paper) & Leak sense & Ultrasound and temperature & - & Real-time. Non-contact system. Edge/cloud comp. Long-range wireless. & General and ATEX industries. & LoRaWAN \\ \hline Emerson Resemount & Acoustic transmitter & Ultrasound and temperature & - & Real-time. Non-contact system. & General and ATEX industries. & WirelessHart \\ \hline \hline \end{tabular}
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Table 2: Comparison of commercial steam traps. the absence of high-frequency sound signals. Unfortunately, both steam traps monitored during the two-day test period were newly installed, and no issues were detected during the testing window provided by the facility. However, the device successfully demonstrated, consistent with findings in the literature, its ability to monitor both temperature and ultrasound signals for this specific application. Conceptualization, R.A., J.O. and C.F. ; methodology, R.A., J.O. and C.F. ; software, R.A.; validation, R.A.; formal analysis, R.A.; investigation, R.A.; data curation, R.A., J.O. and C.F. ; writing--review and editing, R.A., J.O. and C.F. ; visualization, R.A.; project administration, R.A.; funding acquisition, R.A. All authors have read and agreed to the published version of the manuscript. This research was funded by (1) the Catalan government of Spain: Linea d'ajuts: Nuclis de recerca industrial I desenvolupament experimental, Projec'es Economia Circular. Project name: \"INDUYE: Revaloritzaclo del calor residual per a l'eliminacio debateries de Liti en sensoritzacio. Grant number 466989 (2) This research was funded by The Spanish National Research Agency (AEI) grant number PID2020-116890 RB-I00 (AEI/FEDER, EU) under project WISE. (3) This research was funded by the European Commission: H2020 FET Proactive Harvestore Project under grant number 824072; H2020 EIC Pilot Project InduEye 2.0 under grant number 946845.