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Este artículo profundiza en el potencial de los sensores IoT de bajo consumo al aprovechar la sinergia de tres tecnologías esenciales: LoRaWAN, técnicas de recolección de energía y supercapacitores, enfatizando el papel fundamental que desempeñan estas tecnologías en el siempre creciente ámbito de IoT y su contribución a soluciones sustentables de bajo consumo de energía. Se presenta el desarrollo e implementación de un sistema diseñado para informar rápidamente sobre problemas en sistemas metropolitanos de baja tensión. Introduce soluciones de hardware rentables que incorporan métodos no convencionales de almacenamiento de energía, como supercapacitores en lugar de baterías tradicionales. La información recopilada se transmite a un centro de operaciones de red a través de una red LoRaWAN de acceso público. Este sistema ofrece una visión integral del estado de las redes eléctricas, lo que permite la identificación de eventos esporádicos y recurrentes, facilitando la formulación de medidas correctivas y preventivas destinadas a mejorar la calidad de la prestación de servicios., This article delves into the potential of low-power IoT sensors by harnessing the synergy of three essential technologies: LoRaWAN, energy harvesting techniques, and supercapacitors. It emphasizes the pivotal role these technologies play in the ever-expanding realm of IoT and their contribution to sustainable, low-power solutions. The study presents the development and implementation of a system designed for rapid issue reporting within low-voltage metropolitan systems. It introduces cost-effective hardware solutions that incorporate unconventional energy storage methods, such as supercapacitors instead of traditional batteries. The collected information is transmitted to a network operations center via a publicly accessible LoRaWAN network. This system offers comprehensive insights into the condition of electrical networks, enabling the identification of both sporadic and recurring events. It empowers the formulation of corrective and preventive measures aimed at enhancing the quality of service provision.

Energy-harvesting wireless sensors require energy management due to volatile energy sources. Existing energy managers lack adaptability to changing utility requirements or often rely on manually defined utility profiles. To address this, we study an autonomous energy manager that learns utility profiles dynamically, without the need for prior data. The new energy manager ensures that devices adapt to evolving utility needs, extending their operational capabilities in changing environments.

Electric-field energy harvesters (EFEHs) have emerged as a promising technology for harnessing the electric field surrounding energized environments. Current research indicates that EFEHs are closely associated with Tribo-Electric Nano-Generators (TENGs). However, the performance of TENGs in energized environments remains unclear. This work aims to evaluate the performance of TENGs in electric-field energy harvesting applications. For this purpose, TENGs of different sizes, operating in single-electrode mode were conceptualized, assembled, and experimentally tested. Each TENG was mounted on a 1.5 HP single-phase induction motor, operating at nominal parameters of 8 A, 230 V, and 50 Hz. In addition, the contact layer was mounted on a linear motor to control kinematic stimuli. The TENGs successfully induced electric fields and provided satisfactory performance to collect electrostatic charges in fairly variable electric fields. Experimental findings disclosed an approximate increase in energy collection ranging from 1.51% to 10.49% when utilizing TENGs compared to simple EFEHs. The observed correlation between power density and electric field highlights TENGs as a more efficient energy source in electrified environments compared to EFEHs, thereby contributing to the ongoing research objectives of the authors.

Este trabajo de fin de carrera se enfoca en el estudio y diseño de un sistema innovador para la captación de energía de las olas del mar, un recurso renovable y abundante que ofrece un potencial significativo para la generación de energía limpia. Se evalúan las tecnologías existentes y los desafíos asociados con la conversión de la energía de las olas en electricidad utilizable. Se propone un diseño conceptual basado en criterios de eficiencia energética, viabilidad técnica y sostenibilidad ambiental. Además, se analizan los aspectos económicos y el impacto ambiental de la implementación de este sistema. El objetivo principal es contribuir al desarrollo de soluciones energéticas renovables que ayuden a disminuir el cambio climático y promover un futuro más sostenible. Este estudio no solo destaca la factibilidad técnica y económica del aprovechamiento de la energía de las olas, sino que también propone mejoras y recomendaciones para futuras investigaciones y desarrollos en el campo de las energías renovables. Finalmente se presupuestará diseño y se concluirá con una pequeña valoración., This final year project focuses on the study and design of an innovative system for capturing energy from sea waves, a renewable and abundant resource that offers significant potential for the generation of clean energy. Through a comprehensive literature review, existing technologies and the challenges associated with converting wave energy into usable electricity are evaluated. A conceptual design is proposed based on criteria of energy efficiency, technical feasibility, and environmental sustainability. In addition, the economic aspects and the environmental impact of implementing this system are analyzed. The main objective is to contribute to the development of renewable energy solutions that help mitigate climate change and promote a more sustainable future. This study not only highlights the technical and economic feasibility of harnessing wave energy but also proposes improvements and recommendations for future research and developments in the field of renewable energies. Finally, the design will be budgeted and concluded with a small assessment.

Al present document es desenvolupa el procés de creació d’un sistema de posicionament solar en l’azimut i ascensió vertical controlat amb un microcontrolador amb connexió WiFi. Aquesta es connecta a servidors web a través d’API d’on rep les dades de localització, data i hora que el permetrà funcionar de forma autònoma a través d’una sèrie de càlculs gravats a la seva memòria. Al document s’estudia el disseny i elecció del hardware, la programació del software i el disseny i estudi del mecanisme responsable de moure el posicionador així com el prototipat. El software es desenvolupa amb IDE, el llenguatge d’Arduino basat en C++, mentre que el disseny i l’estudi del mecanisme es realitza amb SolidWorks. El treball es focalitza en un entorn d’Arduino utilitzant una placa WEMOS D1 mini. Aquesta placa es caracteritza principalment per disposar de connectivitat WiFi al tindre un processador ESP8266, i alhora, total compatibilitat amb l’entorn IDE d’Arduino, facilitant així la seva programació. En quant a la part mecànica, es pretén dissenyar un mecanisme senzill, de baix cost de producció i baix consum energètic, minimitzant el pes del conjunt i utilitzant hardware eficient. El producte final serà aplicable per a realitzar posicionaments d’una placa fotovoltaica, podent-se aplicar a altres utilitats únicament variant fórmules matemàtiques de codi i detalls estructurals . Un cop analitzada la validesa del projecte, es passa a la producció i realitat del posicionador contemplant tots els elements dissenyats, estudiats i programats prèviament., En el presente documento se desarrolla el proceso de creación de un sistema de posicionamiento solar en el acimut y ascensión vertical controlado con un microcontrolador con conexión Wifi. Esta se conecta a servidores web a través de APIs de donde recibe los datos de localización, fecha y hora que lo permitirá funcionar de forma autónoma a través de una serie de cálculos grabados a su memoria. En el documento se estudia el diseño y elección del hardware, la programación del software y el diseño y estudio del mecanismo responsable de mover el posicionador así como el prototipado. El software se desarrolla con IDE, el lenguaje de Arduino basado en C++, mientras que el diseño y el estudio del mecanismo se realiza con SolidWorks. El trabajo se focaliza en un entorno de Arduino utilizando una placa WEMOS D1 mini. Esta placa se caracteriza principalmente por disponer de conectividad Wifi al tener un procesador ESP8266, y a la vez, total compatibilidad con el entorno IDE de Arduino, facilitando así su programación. Referente a la parte mecánica, se pretende diseñar un mecanismo sencillo, de bajo coste de producción y bajo consumo energético, minimizando el peso del conjunto y utilizando hardware eficiente. El producto final será aplicable para realizar posicionamientos de una placa fotovoltaica, pudiéndose aplicar a otras utilidades únicamente variando fórmulas matemáticas en el código y detalles estructurales. Una vez analizada la validez del proyecto, se pasa a la producción y realidad del posicionador contemplando todos los elementos diseñados, estudiados y programados previamente., The present document describes the development process of a solar positioning system in azimuth and vertical elevation controlled by a microcontroller with WiFi connectivity. This PCB connects to web servers via APIs, receiving positioning data, date, and time, allowing it to operate autonomously using a series of calculations stored in its memory. The document covers the design and hardware selection, software programming, and the study of the mechanism responsible of the positioner movement as well as its prototyping. The software is developed using the Arduino IDE, language which is based on C++, while the mechanism design and study are carried out using SolidWorks. The focus of the work is on an Arduino environment using a WEMOS D1 mini board. This board is characterized primarily by its WiFi connectivity as an ESP8266 processor and full compatibility with the Arduino IDE, making programming easier. Regarding the mechanical aspect, the goal is to design a simple mechanism with low production cost and low energy consumption, minimizing the overall weight and using efficient hardware. The final product will be applicable for positioning of a photovoltaic cell being applicable to other implementations, with variations in mathematical formulas within the code and structure details. Once the validity of the project has been analysed, production and realization of the positioner will proceed, considering all the previouly designed, studied, and programmed elements.

El canvi climàtic, originalment una preocupació limitada a cercles científics, s'ha manifestat com una realitat tangible per a la població global. En anys recents, hem estat testimonis i víctimes d'alguns dels seus impactes més directes, com la intensificació d'esdeveniments climàtics extrems, estius inusualment intensos i sequeres prolongades. Aquest treball se centra en explorar dos pilars fonamentals en la mitigació del canvi climàtic: l'eficiència energètica residencial i l'autoconsum, tant energètic com alimentari. Aquest treball demostra la capacitat de transformar habitatges amb una alta demanda energètica en habitatges amb demandes energètiques netes zero, destacant l'efectivitat d'un disseny energètic òptim i la significativa contribució dels sistemes d'autoconsum energètic i alimentari. Aquestes estratègies no només optimitzen l'ús de recursos, sinó que també redueixen considerablement la petjada de carboni, oferint solucions sostenibles i eficients per afrontar els desafiaments ambientals actuals. El futur implica un retorn a les nostres arrels i un canvi radical en els nostres models de consum actuals, orientant-nos cap a un estil de vida més conscient i respectuós amb l'entorn. Això inclou la promoció de llars més eficients, adaptades a les condicions específiques de cada regió, i la transició cap a models de consum alimentari basats en productes de proximitat i dietes basades íntegrament en vegetals, tot això en harmonia amb el medi ambient., El cambio climático, originalmente una preocupación limitada a círculos científicos, se ha manifestado como una realidad tangible para la población global. En años recientes, hemos sido testigos y víctimas de algunos de sus impactos más directos, como la intensificación de eventos climáticos extremos, veranos inusualmente intensos y sequías prolongadas. Este trabajo se centra en explorar dos pilares fundamentales en la mitigación del cambio climático: la eficiencia energética residencial y el autoconsumo, tanto energético como alimentario. Este trabajo demuestra la capacidad de transformar viviendas con una alta demanda energética en viviendas con demandas energéticas netas cero, destacando la efectividad de un diseño energético óptimo y la significativa contribución de los sistemas de autoconsumo energético y alimentario. Estas estrategias no solo optimizan el uso de recursos, sino que también reducen considerablemente la huella de carbono, ofreciendo soluciones sostenibles y eficientes para enfrentar los desafíos ambientales actuales. El futuro implica un regreso a nuestras raíces y un cambio radical en nuestros modelos de consumo actuales, orientándonos hacia un estilo de vida más consciente y respetuoso con el entorno. Esto incluye la promoción de hogares más eficientes, adaptados a las condiciones específicas de cada región, y la transición hacia modelos de consumo alimentario basados en productos de proximidad y dietas basadas íntegramente en vegetales, todo ello en armonía con el medio ambiente., Climate change, originally a concern limited to scientific circles, has emerged as a tangible reality for the global population. In recent years, we have witnessed and been victims of some of its most direct impacts, such as the intensification of extreme weather events, unusually intense summers, and prolonged droughts. This paper focuses on exploring two fundamental pillars in mitigating climate change: residential energy efficiency and self-sufficiency in both energy and food. This paper demonstrates the ability to transform homes with high energy demands into homes with net zero energy demands, highlighting the effectiveness of optimal energy design and the significant contribution of energy and food self-sufficiency systems. These strategies not only optimize resource use but also significantly reduce the carbon footprint, offering sustainable and efficient solutions to tackle current environmental challenges. The future involves a return to our roots and a radical change in our current consumption models, steering us towards a more conscious and environmentally respectful lifestyle. This includes promoting more efficient homes, tailored to the specific conditions of each region, and transitioning towards food consumption models based on local products and entirely plant-based diets, all in harmony with the environment.

El treball que es presenta a continuació se centra en l'exploració de solucions innovadores en el monitoratge de pacients fora de l'hospital, amb èmfasi en l'autonomia energètica dels dispositius mèdics portables. Es proposa un estudi teòric i pràctic per construir un prototip d'electrocardiògraf alimentat per l'energia de les ones de radiofreqüència. Es revisen tècniques de captació d'energia i s'analitzen les particularitats d’aquestes aplicades a la radiofreqüència. Es realitza un estudi sobre l'electrocardiograma com a diagnòstic mèdic i l'arquitectura d'un electrocardiògraf convencional. La part final aborda la construcció del prototip, incloent la comparació de components, la creació de la placa de circuit imprès i els primers passos en la programació del microcontrolador per verificar el seu funcionament. L'objectiu és desenvolupar una solució que aprofiti l'energia de l'entorn per a dispositius de monitoratge, millorant l'autonomia i la llibertat dels pacients en règim no hospitalari., El trabajo que se presenta a continuación se centra en la exploración de soluciones innovadoras en la monitorización de pacientes fuera del hospital, con énfasis en la autonomía energética de los dispositivos médicos portátiles. Se propone un estudio teórico y práctico para construir un prototipo de electrocardiograma alimentado por la energía de las ondas de radiofrecuencia. Se revisan técnicas de captación de energía y se analizan las particularidades de estas aplicadas a la radiofrecuencia. Se realiza un estudio sobre el electrocardiograma como diagnóstico médico y la arquitectura de un electrocardiograma convencional. La parte final aborda la construcción del prototipo, incluyendo la comparación de componentes, la creación de la placa de circuito impreso y los primeros pasos en la programación del microcontrolador para verificar su funcionamiento. El objetivo es desarrollar una solución que aproveche la energía del entorno para dispositivos de monitorización, mejorando la autonomía y la libertad de los pacientes en régimen no hospitalario., The work presented below focuses on exploring innovative solutions in monitoring patients outside the hospital, with an emphasis on the energy autonomy of portable medical devices. A theoretical and practical study is proposed to build a prototype electrocardiogram powered by the energy of radiofrequency waves. Energy harvesting techniques are reviewed, and the specificities of their application to radiofrequency are analysed. A study is conducted on the electrocardiogram as a medical diagnosis tool and the architecture of a conventional electrocardiogram. The final part addresses the construction of the prototype, including component comparisons, the creation of the printed circuit board, and the initial steps into programming the microcontroller to verify its operation. The objective is to develop a solution that harnesses environmental energy for monitoring devices, enhancing the autonomy and freedom of patients undergoing non-hospital care.

Piezoelectric energy harvesters (PEHs) hold promises for revolutionizing railway structural health monitoring (SHM). However, the challenges of designing high-robust PEHs for handling complex and ever-shifting vibrations in practical railway scenarios remain formidable. Unlike conventional methods that align the fundamental frequency of the PEH with the dominant frequency of the vibration source, this study employs an event-driven enhancement method. This study commences by employing a high-fidelity dynamic model of the PEH and an advanced vehicle-track coupled dynamic model to evaluate energy harvesting efficiency across various railway scenarios. The vehicle-induced track vibrations are predicted across various train speeds, track structures, and track irregularities, considering 12 distinct vehicle-track conditions and totaling 3600 simulation datasets, each representing a specific event. We employ the particle swarm optimization (PSO) algorithm to identify optimal PEH designs for different events. To streamline this process, instead of offering one optimal solution for each event, we employ the K-means algorithm to cluster similar events. Subsequently, we choose the centroid design for each cluster as the representative solution for events within that cluster. This approach allows us to use a limited number of representative PEHs to effectively address most events across different clusters. Finally, we thoroughly examine and evaluate the dynamic responses of these representative designs to demonstrate their robust performance. This study explores PEH design optimization from a fresh perspective, bridging the gap between theoretical design and practical implementation in rail transportation systems.

This paper proposes a novel wake-induced vibration (WIV)-based energy harvesting system consisting of two bluff bodies. An inverted C-shaped bluff body is stationary installed at the upstream position to generate an interference wake street, and a cylinder bluff body equipped with a transducer is elastically suspended at the downstream position to harness WIV energy. The hydrodynamics and energy harvesting (EH) performance of the proposed system are investigated via experimental studies. The reduced velocity (U{*}) ranging from 2 to 14 (the corresponding Reynolds number ranging from 15100 to 106200) is considered in the present study. It is found that the wake generated by the inverted C-shaped bluff body significantly affects the EH performance. Enlarging the opening angle (alpha) of the C-shaped bluff body increases the vibration amplitude of the downstream cylinder, thereby increasing the harvested power. When the spacing (L) between two bluff bodies is two times the cylinder diameter (D), the wake-induced vibration (WIV) mode is observed, while the combined WIV and wake galloping (WG) mode occurs when alpha is 150 degrees, and L equals 3D or 4D. The average drag coefficient becomes negative when L is 2D, 3D, or 4D. By carefully configuring a C-shaped bluff body, the wake generated by it can bring an augmenting effect on the vibration of the downstream EH cylinder. For example, the RMS power output of the proposed EH system reaches a maximum of 0.31 W at U{*} = 8 and L = 4D, which is 300% greater than that of its traditional counterpart. Furthermore, after a number of case studies, it is identified that the proposed EH system can achieve the best performance when alpha is 150 degrees and L = 2D.

Energy harvesting is often hailed as the great savior of Internet of Things and wireless sensor systems. It will provide all the energy needed to run your thing and a battery is barely needed. How true is this, and where in the world is it this easy? This paper is an investigation of how much energy is actually available from sunlight in the dead of the Scandinavian winter. The paper also measures and evaluates whether vibrational energy harvesting mated to industrial equipment can power a wireless sensor system. With the small amounts of energy available, it is also prudent to investigate what can be done in embedded software to be better matched with a energy harvested power source. The communication protocol $I^2C$ and the power draw of its operation is investigated, and the effect of pull-up resistor value and bitrate is shown to be small, but impactful on long-term system power draw. This paper shows that photovoltaic energy harvesting in central Sweden is feasible, even in the dead of winter. Vibrational energy harvesting is harder to master, and the results are inconclusive whether it possible with a better harvesting setup., Energiutvinning hyllas ofta som den stora räddaren i nöden för Internet of Things och trådlösa sensorsystem. Det kommer att kunna tillhandahålla all energi som behövs för att driva en enhet och batterier är knappt nödvändiga. Hur sant är detta, och var i världen är det så enkelt? Denna artikel innehåller en fältstudie som undersöker hur mycket energi som faktiskt är tillgänglig från solljus i Norden. Utöver det undersöks också om vibrationer från industriell utrustning kan driva en trådlös sensor. Med de små mängderna energi som är tillgängliga är det också klokt att undersöka vad som kan göras i mjukvara för att vara bättre anpassad för en energiutvinningsbaserad källa. Kommunikationsprotokollet $I^2C$ och dess strömförbrukning undersöks, och effekten av pull-up resistorvärde och kommunikationshastighet visar sig ha en liten, men påvisbar effekt på långsiktig strömförbrukning. Denna rapport visar att energiutvinning från solceller i centrala Sverige kan fungera, även mitt i vintern. Vibrationsenergiutvinning är svårare att bemästra, och resultaten är inte entydiga, och vidare studier behövs för att visa om det är möjligt med en bättre utvinningskonfiguration.

A hydro turbine is a rotatory machine that converts water’s kinetic and potential energy into mechanical work. This thesis aims to investigate the possibility of replacing pressure-reducing valves (PRVs) in water distribution systems (WDS) with hydro turbines by constructing a framework on how to automize the design process of a turbine blade in such a turbine and by analyzing different control strategies so that the turbine could function as a pressure reducing valve. Bayesian optimization has been used to optimize the black-box objective function describing the geometry of a turbine runner blade. The objective function also contains a computational fluid dynamics (CFD) solver capable of running simulations on the blade. The results from the simulations are used to update the blade design, this will be carried out iteratively for a fixed number of iterations in this thesis 140 iterations were performed. A Simscape model of a WDS was used to evaluate different control strategies; the final control strategy uses a feedforward mid-ranging approach to coordinate the output signal from the different controllers. The thesis results show that it is possible to automate the design process of a turbine blade by using Bayesian optimization to maximize an objective function value obtained from CFD simulations and automatically update the geometry based on previous simulation results.The control strategy shows that it is possible to keep the downstream pressure at a desired reference pressure even though the system is subjected to both up-and downstream disturbances., En vattenturbin är en roterande maskin som omvandlar kinetisk och potentiell energi från vatten till mekaniskt arbete. Detta arbete syftar till att undersöka möjligheten att ersätta tryckreduceringsventiler i distributionsnät för vatten med vattenturbiner genom att konstruera ett tillvägagångssätt för hur man automatiserar designprocessen för ett turbinblad i en sådan turbin och att analysera olika reglerstrategier så att turbinen kan fungera som en tryckreduceringsventil. Bayesiansk optimering har använts för att optimera en objekt funktion som beskriver geometrin för ett turbinblad. Objekt funktionen innehåller även en CFD lösare som kan utföra simuleringar på bladet. Resultaten från simuleringarna används sedan för att uppdatera bladets design, detta utförs iterativt för ett bestämt antal iterationer, i detta arbete utfördes 140 iterationer. En Simscape-modell av ett distributionsnät användes för att utvärdera olika reglerstrategier, den slutliga regulatorn använder sig av en feedforward mid-ranging strategi för att samordna mellan utsignalen från de olika regulatorerna. Resultaten av detta arbete visar att det är möjligt att automatisera designprocessen för ett turbinblad genom att använda Bayesiansk optimering för att maximera ett funktionsvärde erhållet från CFD-simuleringar och automatiskt uppdatera geometrin baserat på tidigare simuleringsresultat. Reglerstrategin visar att det är möjligt att hålla nedströmstryck vid ett önskat referenstryck även om systemet utsätts för både uppströms- och nedströmsstörning

In recent years, the number of devices connected to theInternet of Things (IoT) has substantially increasedand is expected to double by the end of this decade.However, a significant barrier to the full realization ofIoT potential is the issue of energy management. Traditional battery-powered IoT devices face limitationssuch as finite operational lifetimes and high maintenance costs. This has led to new developments in thefield, enabling batteryless devices that harvest ambient energy. Despite these advancements, these devicesare vulnerable to energy attacks. One specific typeof energy attack is a synchronization attack, where anadversary manipulates environmental conditions, causing devices in a Wireless Sensor Network to synchronize (WSN). Synchronization between nodes in a WSNleads to packet collisions, which in turn causes performance degradation. This thesis proposes mitigationstrategies against synchronization attacks by utilizingvoltage activation thresholds to desynchronize nodes.

This thesis explores the viability of various energy harvesting technologies for powering micro-scale IoT devices in outdoor environments, specifically for products developed by Thule Sweden AB. Through a comprehensive literature review and experimental testing, we evaluated the performance of solar panels and piezoelectric systems to identify sustainable power solutions that could replace or reduce dependence on traditional battery power. Our methodology involved controlled laboratory tests and real-world applications on car roof boxes and bike trailers to assess the technologies under practical conditions. The experiments aimed to achieve a minimum daily energy output of 20 Joules. This target was chosen with reference to the energy consumption data of a specific IoT device used by Thule. The results demonstrated that while both solar and piezoelectric technologies have their possibilities and limitations, they hold promise for integration into IoT applications, offering a step towards more sustainable product designs. These findings contribute to a broader understanding of energy harvesting’s potential to reduce environmental impact and enhance the self-sufficiency of energy production in outdoor IoT applications., Denna avhandling undersöker genomförbarheten av olika teknologier för energiutvinning för att driva mikroskaliga IoT-enheter i utomhusmiljöer, specifikt för produkter utvecklade av Thule Sweden AB. Genom en omfattande litteraturöversikt och experimentella tester utvärderade vi prestandan hos solpaneler och piezoelektriska system i syfte att identifiera hållbara energilösningar som kunde ersätta eller minska beroendet av traditionella batterier. Vår metodik inkluderade både kontrollerade laboratorietester och praktiska tillämpningar på takboxar och cykelkärror för att bedöma teknologierna under praktiska förhållanden. Experimenten syftade till att uppnå en minsta daglig energiproduktion på 20 joule. Detta mål baseras på energiförbrukningsdata från en specifik IoT-enhet som används av Thule. Resultaten visade att även om både sol- och piezoelektriska teknologier har sina fördelar och begränsningar, har de potential för integration i IoT-applikationer, vilket erbjuder ett steg mot mer hållbara produktdesigner. Dessa fynd bidrar till en bredare förståelse för energiutvinningens potential att minska miljöpåverkan och förbättra självförsörjningen av energiproduktion för IoT-applikationer utomhus.

Energy harvesting technologies are crucial for the future green transition. Research shows the versatility and efficiency of integrated energy harvesting solutions. Economic advantages, enhanced energy efficiency, and reduced reliance on conventional power sources can be achieved with well implemented systems. Furthermore, there are environmental benefits from using more renewable energy sources due to fewer emissions from battery production and replacement. One of the challenges with system implementation is achieving high efficiency for various energy sources and system loads. This study aimed to showcase the design steps for crucial system blocks to aid in designing complete energy harvesting systems. The designs are done in a 180 nm CMOS process. A literature study, including recent research on capacitive and inductive converters, gave insight into the limitations of the different topologies. The study also included other crucial blocks for efficient energy harvesting systems, such as Maximum power point tracking and cold-start. In the study, commercially available energy harvesting chips are discussed, and it is concluded that the market is limited regarding alternatives for a wide range of systems. A microcontroller is needed for an adaptable system. For the study, an additional aim was to provide support for an MSP430L092, a low-power microcontroller from Texas Instruments. The support included level shifters and supply voltage generation. Due to time constraints, not all blocks were designed. The designed blocks are a boost converter, level shifters and a Pulse-width modulation generation network composed of a comparator and oscillator. Other blocks needed in efficient energy harvesting systems are included as short discussions of possible implementations from other research and commercially available components. Simulation of the boost converter showed that the main losses are from the non ideal inductor. These were minimised by using a higher switching fre

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

Monitoring water flow helps to identify leaks and wastage, leading to better management of water resources and conservation of this precious resource. To address this challenge, there is a need for an efficient and sustainable water management system. This paper presents an Internet of Things (IoT) based solution that involves retrofitting existing analog water meters using readily available off-the-shelf electronic components. Real-time data collection and analysis are performed through edge computation, which locally processes water meter images captured by the camera and extracts water meter readings. These readings are transmitted to the cloud for storage and further analysis. Various strategies have been implemented to optimize supply-current usage, preserving charge-discharge cycles of solar-powered batteries even in adverse environmental conditions. To streamline the firmware update process for multiple connected devices, a broadcasting technique is employed, offering the benefits of reduced manual labor and time savings. To assess the reliability and performance of developed solution, field deployment is conducted over several months, enabling the characterization of water usage patterns across different locations. Integrating energy harvesting capabilities into system reduces maintenance costs and promotes eco-friendly energy practices. Overall, this solution offers an effective and comprehensive approach towards achieving efficient and sustainable water management., Validerad;2024;Nivå 2;2024-07-02 (joosat);Full text license: CC BY-NC-ND 4.0; Funder: Technology Innovation Hub- Information Technogy (TIH-IT) CHANAKYA Fellowship Program; TIH Foundation for Internet of Things (loT) and Internet of Everything (loE) (Grant Number: TIH loT/2023-03/HRD/CHANAKYA/SL/CFP-018): Ministry of Electronics and Information Technology (MEITY), Government of India (Grant Number: 3070665 (2020)

Communication networks can achieve self-sustainability with the help of reconfigurable intelligent surfaces (RIS) that direct electromagnetic waves toward zero-energy devices (ZEDs) for energy harvesting. The harvested energy charges the ZEDs' batteries, reduces their dependency on external energy sources and enables energy neutrality. In this letter, we propose a dynamic algorithm that adjusts the joint RIS and TX phases based on the battery levels to maximize a weighted-sum power metric favoring ZEDs with lower battery levels. The simulation results show that threshold-based weighting slightly underperforms compared to the weighting with optimal parameters while requiring less data exchange with the network entity manager., QC 20240903

The booming evolution of portable, wearable electronic devices, wireless sensors, and integrated microelectronics has stimulated the need for miniaturized power supply modules. Energy harvesters, which harness the environmental energy for electricity use, and micro super capacitors (MSCs),known for the small form factor and rapid power delivery, provide energy efficient solutions. Meanwhile, the demand for sustainable development hasdriven the research towards environmental and ecological-friendly energy solutions. In light of this, utilizing paper as a substrate offers a promising avenue due to its sustainability, lightweight nature, disposability, and availability. Integrating energy harvesters and micro super capacitors into on paper micro-power sources holds the potential for ready-to-use smartelectronics, such as biosensors for detection and diagnostics. Nonetheless, the progress of on-paper MSCs is still in its infancy encountering challenges in appropriate material selection, structure, and fabrication design. 2D material MXene and conducting polymer PEDOT:PSS hold promises for on-paper MSCs thanks to their hydrophilic nature and excellent electrochemical properties. In terms of energy harvesting units,hydrovoltaic technologies that generate electricity from water movement offer a sustainable energy solution, while triboelectric nanogenerators (TENGs) harness the ubiquitous mechanical energy in the environment to produce electrical power. Such electric energy can be directly utilized or stored with the assistance of MSCs for later consumption. However, integrating energy harvesting and storage components on paper involves complex material and fabrication requirements. This thesis aims at enhancing the rate capability (thecharge and discharge ability at high rates while maintaining the storage capacity) of on-paper MSCs, advancing the development of hydrovoltaic and TENGs energy harvesters and eventually integrating TENGs and MSCs to a non-paper power supply., Den snabba utvecklingen av mindre, bärbara, elektroniska apparater medtrådlösa sensorer, integrerade kretsar och displayer har tvingat fram ett behov av små strömförsörjningsenheter som kan driva denna typ av elektronikprodukter. En möjlighet är att använda miniatyriserade ”energiskördare” som omvandlar mekanisk, termisk eller annan energi som genereras i omgivningen till elektrisk energi. Exempel påsådan energi som finns i vår närmiljö kan vara solljus, vågrörelse, kroppsrörelse och kroppsvärme. Genom att konstruera t ex piezo- eller triboelektriskageneratorer, som tar upp tryck och rörelse och omvandlar detta till elektrisk spänning, kan man generera en ström som skulle kunna räcka till för att driva en liten elektrisk krets. Funktionen av en sådan strömförsörjningsenhet kan också förbättras genom att addera ett batteri som kan lagra den genererade elektriska energin, t ex genom en liten kondensator med lång tidskonstant, en sk mikrosuperkondensator. Denna avhandling visar olika möjligheter att bygga användbara små generatorer och kraftmoduler som uppfyller de tekniska kraven för effektförsörjning av bärbar elektronik. I avhandling strävas också efter att uppfylla hållbarhetsmålen och att minska miljöbelastningen genom att använda ”gratisenergi” i vår omgivning och även utnyttja material och processer som har minimal negativ påverkan på miljön. Den framtagna tekniken baseras på att trycka elektriska komponenter och kretsar på papper, vilket uppfyller kraven på miljövänlighet och hållbarhet. Produkten kan också göras liten, har låg vikt och är böjlig, vilket gör den väl lämpad för bärbara applikationer. Den blir också billig att tillverka och, genom att miljövänliga material används, kan den slängas eller brännas utan miljöpåverkan, till skillnad från mycket av den elektronik som vi använder idag. Inledningsvis behandlas framtagningen av ett ledande bläck som också har nödvändiga egenskaper för att kunna tryckas på papper. Aktiva substanser ibläcket är 2D-materiale, QC 20240508

Interests in small-scale turbomachinery are gaining momentum, particularly around waste heat recovery using Organic Rankine Cycle (ORC), energy harvesting, pico-hydro, refrigeration and heat pumps and small-scale power generation. These applications demand to have economical, simple construction, and reasonably efficient machines. The performance of bladed turbomachine at a small scale is poor mainly due to viscous losses and relatively large clearances. In some cases, like ORC, it requires a lubrication system, making it complex and costly. Bladeless or Tesla turbomachinery is seen as one of the solutions for these applications due to its simple construction and cost-effectiveness. However, the experimental efficiency of the bladeless turbines/compressors is found in the low region, <40%. In this article, the performance of a bladeless turbine is investigated using a vaneless volute configuration, making the turbine stator-less (vaneless volute) and bladeless (vaneless rotor). This study presents numerical and experimental performance investigation with a volute as a stator of the bladeless rotor. Three-dimensional (3D) Numerical results show very promising performance of the turbine with total to static efficiencies calculated above 65%. In the second part of the article, turbine prototype components, assembly, and test setup are discussed. Experimental maximum efficiency of 41.5 +/- 0.88% at 3.5kg/s@5000rpm and power of 915W is obtained. This is the highest recorded efficiency for the Tesla turbine in peer-reviewed research. The overall turbine performance from 3D numerical simulation with ventilation and mechanical losses is compared with experimental results. This work demonstrates that the proposed stator-less/volute configuration provides an efficient way for bladeless or Tesla turbines, particularly for low-head applications.

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

Monitoring water flow helps to identify leaks and wastage, leading to better management of water resources and conservation of this precious resource. To address this challenge, there is a need for an efficient and sustainable water management system. This paper presents an Internet of Things (IoT) based solution that involves retrofitting existing analog water meters using readily available off-the-shelf electronic components. Real-time data collection and analysis are performed through edge computation, which locally processes water meter images captured by the camera and extracts water meter readings. These readings are transmitted to the cloud for storage and further analysis. Various strategies have been implemented to optimize supply-current usage, preserving charge-discharge cycles of solar-powered batteries even in adverse environmental conditions. To streamline the firmware update process for multiple connected devices, a broadcasting technique is employed, offering the benefits of reduced manual labor and time savings. To assess the reliability and performance of developed solution, field deployment is conducted over several months, enabling the characterization of water usage patterns across different locations. Integrating energy harvesting capabilities into system reduces maintenance costs and promotes eco-friendly energy practices. Overall, this solution offers an effective and comprehensive approach towards achieving efficient and sustainable water management., Validerad;2024;Nivå 2;2024-07-02 (joosat);Full text license: CC BY-NC-ND 4.0; Funder: Technology Innovation Hub- Information Technogy (TIH-IT) CHANAKYA Fellowship Program; TIH Foundation for Internet of Things (loT) and Internet of Everything (loE) (Grant Number: TIH loT/2023-03/HRD/CHANAKYA/SL/CFP-018): Ministry of Electronics and Information Technology (MEITY), Government of India (Grant Number: 3070665 (2020)

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

Microgrids are localized, independent power grids that can operate while connected to the larger electrical grid. These systems make intelligent decisions regarding power management and use an array of components to monitor power generation, consumption, and environmental conditions. While this technology can save end users money, the complexity of installation and maintenance has limited the adoption of microgrids in residential spaces. To simplify this technology for end users, the next evolution of microgrid components includes sensors that are wireless and ambiently powered. Even with a microgrid installed, significant energy is wasted in residential spaces. To address this loss, energy harvesting circuits can be incorporated into microgrid sensors, enabling them to recapture otherwise wasted environmental energy. Light, heat, radio frequency (RF) energy, mechanical energy, and 60 Hz noise from power lines are all abundant in most residential spaces and can be harvested to power microgrid components. Equipping microgrid sensors with energy harvesters simplifies the end user experience by eliminating the need for cable routing. Implementing energy harvesting techniques results in a microgrid that is easier to deploy, cleaner, and requires less maintenance. Developing this type of sensor is not only feasible, but sensible and can be constructed using off-the-shelf components. My research led me to conclude that the most effective strategy for designing an energy harvesting sensor is to combine energy harvesting technologies with battery power. By delegating smaller loads away from the harvesting integrated circuit (IC), its full harvesting potential is utilized, maximizing energy collection for the power-hungry transmitter. Simultaneously, a small coin-cell battery can sustain the remaining components, ensuring over a decade of functionality. This thesis explores the feasibility and design of a hybrid battery and energy harvesting sensor. The developed system bloc

This thesis explores the viability of various energy harvesting technologies for powering micro-scale IoT devices in outdoor environments, specifically for products developed by Thule Sweden AB. Through a comprehensive literature review and experimental testing, we evaluated the performance of solar panels and piezoelectric systems to identify sustainable power solutions that could replace or reduce dependence on traditional battery power. Our methodology involved controlled laboratory tests and real-world applications on car roof boxes and bike trailers to assess the technologies under practical conditions. The experiments aimed to achieve a minimum daily energy output of 20 Joules. This target was chosen with reference to the energy consumption data of a specific IoT device used by Thule. The results demonstrated that while both solar and piezoelectric technologies have their possibilities and limitations, they hold promise for integration into IoT applications, offering a step towards more sustainable product designs. These findings contribute to a broader understanding of energy harvesting’s potential to reduce environmental impact and enhance the self-sufficiency of energy production in outdoor IoT applications., Denna avhandling undersöker genomförbarheten av olika teknologier för energiutvinning för att driva mikroskaliga IoT-enheter i utomhusmiljöer, specifikt för produkter utvecklade av Thule Sweden AB. Genom en omfattande litteraturöversikt och experimentella tester utvärderade vi prestandan hos solpaneler och piezoelektriska system i syfte att identifiera hållbara energilösningar som kunde ersätta eller minska beroendet av traditionella batterier. Vår metodik inkluderade både kontrollerade laboratorietester och praktiska tillämpningar på takboxar och cykelkärror för att bedöma teknologierna under praktiska förhållanden. Experimenten syftade till att uppnå en minsta daglig energiproduktion på 20 joule. Detta mål baseras på energiförbrukningsdata från en specifik IoT-enhet som används av Thule. Resultaten visade att även om både sol- och piezoelektriska teknologier har sina fördelar och begränsningar, har de potential för integration i IoT-applikationer, vilket erbjuder ett steg mot mer hållbara produktdesigner. Dessa fynd bidrar till en bredare förståelse för energiutvinningens potential att minska miljöpåverkan och förbättra självförsörjningen av energiproduktion för IoT-applikationer utomhus.

A hydro turbine is a rotatory machine that converts water’s kinetic and potential energy into mechanical work. This thesis aims to investigate the possibility of replacing pressure-reducing valves (PRVs) in water distribution systems (WDS) with hydro turbines by constructing a framework on how to automize the design process of a turbine blade in such a turbine and by analyzing different control strategies so that the turbine could function as a pressure reducing valve. Bayesian optimization has been used to optimize the black-box objective function describing the geometry of a turbine runner blade. The objective function also contains a computational fluid dynamics (CFD) solver capable of running simulations on the blade. The results from the simulations are used to update the blade design, this will be carried out iteratively for a fixed number of iterations in this thesis 140 iterations were performed. A Simscape model of a WDS was used to evaluate different control strategies; the final control strategy uses a feedforward mid-ranging approach to coordinate the output signal from the different controllers. The thesis results show that it is possible to automate the design process of a turbine blade by using Bayesian optimization to maximize an objective function value obtained from CFD simulations and automatically update the geometry based on previous simulation results.The control strategy shows that it is possible to keep the downstream pressure at a desired reference pressure even though the system is subjected to both up-and downstream disturbances., En vattenturbin är en roterande maskin som omvandlar kinetisk och potentiell energi från vatten till mekaniskt arbete. Detta arbete syftar till att undersöka möjligheten att ersätta tryckreduceringsventiler i distributionsnät för vatten med vattenturbiner genom att konstruera ett tillvägagångssätt för hur man automatiserar designprocessen för ett turbinblad i en sådan turbin och att analysera olika reglerstrategier så att turbinen kan fungera som en tryckreduceringsventil. Bayesiansk optimering har använts för att optimera en objekt funktion som beskriver geometrin för ett turbinblad. Objekt funktionen innehåller även en CFD lösare som kan utföra simuleringar på bladet. Resultaten från simuleringarna används sedan för att uppdatera bladets design, detta utförs iterativt för ett bestämt antal iterationer, i detta arbete utfördes 140 iterationer. En Simscape-modell av ett distributionsnät användes för att utvärdera olika reglerstrategier, den slutliga regulatorn använder sig av en feedforward mid-ranging strategi för att samordna mellan utsignalen från de olika regulatorerna. Resultaten av detta arbete visar att det är möjligt att automatisera designprocessen för ett turbinblad genom att använda Bayesiansk optimering för att maximera ett funktionsvärde erhållet från CFD-simuleringar och automatiskt uppdatera geometrin baserat på tidigare simuleringsresultat. Reglerstrategin visar att det är möjligt att hålla nedströmstryck vid ett önskat referenstryck även om systemet utsätts för både uppströms- och nedströmsstörning

Energy harvesting is often hailed as the great savior of Internet of Things and wireless sensor systems. It will provide all the energy needed to run your thing and a battery is barely needed. How true is this, and where in the world is it this easy? This paper is an investigation of how much energy is actually available from sunlight in the dead of the Scandinavian winter. The paper also measures and evaluates whether vibrational energy harvesting mated to industrial equipment can power a wireless sensor system. With the small amounts of energy available, it is also prudent to investigate what can be done in embedded software to be better matched with a energy harvested power source. The communication protocol $I^2C$ and the power draw of its operation is investigated, and the effect of pull-up resistor value and bitrate is shown to be small, but impactful on long-term system power draw. This paper shows that photovoltaic energy harvesting in central Sweden is feasible, even in the dead of winter. Vibrational energy harvesting is harder to master, and the results are inconclusive whether it possible with a better harvesting setup., Energiutvinning hyllas ofta som den stora räddaren i nöden för Internet of Things och trådlösa sensorsystem. Det kommer att kunna tillhandahålla all energi som behövs för att driva en enhet och batterier är knappt nödvändiga. Hur sant är detta, och var i världen är det så enkelt? Denna artikel innehåller en fältstudie som undersöker hur mycket energi som faktiskt är tillgänglig från solljus i Norden. Utöver det undersöks också om vibrationer från industriell utrustning kan driva en trådlös sensor. Med de små mängderna energi som är tillgängliga är det också klokt att undersöka vad som kan göras i mjukvara för att vara bättre anpassad för en energiutvinningsbaserad källa. Kommunikationsprotokollet $I^2C$ och dess strömförbrukning undersöks, och effekten av pull-up resistorvärde och kommunikationshastighet visar sig ha en liten, men påvisbar effekt på långsiktig strömförbrukning. Denna rapport visar att energiutvinning från solceller i centrala Sverige kan fungera, även mitt i vintern. Vibrationsenergiutvinning är svårare att bemästra, och resultaten är inte entydiga, och vidare studier behövs för att visa om det är möjligt med en bättre utvinningskonfiguration.

In recent years, the number of devices connected to theInternet of Things (IoT) has substantially increasedand is expected to double by the end of this decade.However, a significant barrier to the full realization ofIoT potential is the issue of energy management. Traditional battery-powered IoT devices face limitationssuch as finite operational lifetimes and high maintenance costs. This has led to new developments in thefield, enabling batteryless devices that harvest ambient energy. Despite these advancements, these devicesare vulnerable to energy attacks. One specific typeof energy attack is a synchronization attack, where anadversary manipulates environmental conditions, causing devices in a Wireless Sensor Network to synchronize (WSN). Synchronization between nodes in a WSNleads to packet collisions, which in turn causes performance degradation. This thesis proposes mitigationstrategies against synchronization attacks by utilizingvoltage activation thresholds to desynchronize nodes.

Energy harvesting technologies are crucial for the future green transition. Research shows the versatility and efficiency of integrated energy harvesting solutions. Economic advantages, enhanced energy efficiency, and reduced reliance on conventional power sources can be achieved with well implemented systems. Furthermore, there are environmental benefits from using more renewable energy sources due to fewer emissions from battery production and replacement. One of the challenges with system implementation is achieving high efficiency for various energy sources and system loads. This study aimed to showcase the design steps for crucial system blocks to aid in designing complete energy harvesting systems. The designs are done in a 180 nm CMOS process. A literature study, including recent research on capacitive and inductive converters, gave insight into the limitations of the different topologies. The study also included other crucial blocks for efficient energy harvesting systems, such as Maximum power point tracking and cold-start. In the study, commercially available energy harvesting chips are discussed, and it is concluded that the market is limited regarding alternatives for a wide range of systems. A microcontroller is needed for an adaptable system. For the study, an additional aim was to provide support for an MSP430L092, a low-power microcontroller from Texas Instruments. The support included level shifters and supply voltage generation. Due to time constraints, not all blocks were designed. The designed blocks are a boost converter, level shifters and a Pulse-width modulation generation network composed of a comparator and oscillator. Other blocks needed in efficient energy harvesting systems are included as short discussions of possible implementations from other research and commercially available components. Simulation of the boost converter showed that the main losses are from the non ideal inductor. These were minimised by using a higher switching fre

Underground tunnels contain toxic, hazardous gases or lack oxygen. Therefore, providing the safety of personnel working in underground tunnels by monitoring oxygen, combustible or toxic gases is important. Wearable sensor networks are used in various applications such as oxygen monitoring. Some wearable sensor networks for gas monitoring are powered by batteries. Given the finite lifetime of batteries and the long term stay of underground personnel in these places, e.g. as a result of incidents, having a wearable sensor node with a stable power supply is crucial to conducting oxygen monitoring and notifying the emergency conditions. In order to provide a battery-less operation of the wearable sensor node, one approach is to use ambient energy sources. Considering the fact that the human body can survive only a few minutes without oxygen, the goal of our work is to investigate whether the power generated as a result of temperature difference between the body and ambient air is sufficient to power a sensor node for conducting oxygen detection every 20 seconds. Therefore, we present the development of a wearable sensor node for oxygen detection. The platform consists of a thermoelectric generator (TEG) converter, a sensing circuit for an electrochemical gas sensor and a power management circuit. Our experimental results with our platform indicate that a temperature difference of 6 degrees C between the body and the ambient air and storing the harvested energy in a capacitor ensure the autonomous operation of the wearable sensor node for measurements and alarm actuation conducted every 15 seconds. The period between the measurements could even become less than 15 seconds in underground tunnels as the temperature difference increases.

Sogenannte Wearables zur Messung und Aufzeichnung diverser Körperaktivitäten und -parametern spielen in der heutigen Zeit eine immer bedeutendere Rolle – von Smartwatches über Fitnessarmbänder bis hin zum einfachen Schrittzähler auf dem Smartphone. Diese Tools können auch im Bereich der Medizin zu einer besseren und komfortableren Überwachung von Patienten beitragen. Durch smarte Textilien eröffnen sich neue Möglichkeiten zur Erfassung der Vitalparameter vor allem im Bereich der Langzeitüberwachung sowie bei Messungen während verschiedenster Aktivitäten. Künftig ist eine Anwendung dieser Technologien auch in Bereichen der Telemedizin vorstellbar. In dieser Masterarbeit wird eine Elektronik entworfen, die es im passiven Betrieb ermöglicht, mit Hilfe von Energy Harvesting und Backscattering im UHF-RFID-Bereich, das von einem smarten Textil gemessene EKG auszulesen. Die Arbeit baut auf einem bestehenden, aber zum Zeitpunkt der Übernahme nicht funktionierenden, Projekt auf. Des Weiteren lassen sich die Ziele der Masterarbeit nicht mit dem Design des übernommenen Projekts vereinbaren, weshalb ein grundlegend neues Konzept erarbeitet wird. Die durchgeführten Versuche und Messungen belegen die grundlegende Funktionalität des in dieser Masterarbeit entwickelten Schaltungs- und PCB-Designs, sowie der Software. Die unzureichende und schwankende Datenrate im Backward-Link für eine präzise EKG-Aufzeichnung sowie die Instabilitäten in der Versorgungsspannung führen dazu, dass abschließend weitere Optimierungsmöglichkeiten des Systems aufgezeigt werden., Wearables for measuring and recording various body activities and parameters are becoming increasingly important these days – ranging from smartwatches and fitness bracelets to simple pedometers on smartphones. These tools also have the potential to contribute to better and more comfortable patient monitoring in the medical field. Smart textiles open up new opportunities, particularly for long-term monitoring and measurements during various activities. In the future, the application of these technologies in telemedicine settings is conceivable. This master's thesis focuses on designing electronics that enable passive operation by using energy harvesting and backscattering in the UHF-RFID band to read the ECG measured by a smart textile. The work builds upon an existing project, which was non-functional at the time of the acquisition. Additionally, the objectives of the master's thesis cannot be met with the design inherited from the previous project, so a fundamentally new concept must be developed. The experiments and measurements conducted confirm the basic functionality of the circuit and PCB design, as well as the software developed in this thesis. However, due to fluctuating and insufficient data rates for accurate EKG recordings in the backward link, and because of voltage supply instabilities resulting from energy harvesting with the developed code, further optimization possibilities for the system are ultimately demonstrated., Simon Marxgut, BSc, Masterarbeit Universität Innsbruck 2024

The growth of Internet of Things (IoT) networks has made battery replacement in IoT devices increasingly challenging. This issue is particularly pronounced in scenarios with a large number of IoT devices, in locations where IoT devices are difficult to access, or when frequent replacement is necessary. The risk of losing or forgetting some IoT devices also exists, leading to a risk of hazardous chemical leakage and e-waste in nature. Radio Frequency(RF) wireless power transfer (WPT) offers an alternative solution for powering these devices. Moreover, it has been observed that the receivers absorb less than one-millionth of the transmitter energy while surrounding objects absorb the remainder. This situation opens up the possibility of leveraging existing wireless infrastructures, such as base stations (BSs), to charge IoT devices. In this thesis, we focus on analyzing the feasibility and limitations of battery-less operation of IoT devices using RF WPT technology, along with energy harvesting (EH) from existing wireless communication infrastructure. We explore both indoor and outdoor scenarios for powering IoT devices. Initially, we consider an outdoor environment where an IoT device periodically harvests energy from existing BSs and transmits a data packet related to sensor measurement. We analyze the coverage range of energy harvesting from a BS for powering IoT devices, which shows a tradeoff between the coverage range and the rate of sensor measurements. Additionally, we compare the operational domain in terms of the range and measurement rate for WPT and battery-powered technologies. Furthermore, we consider the coverage probability for a multi-site scenario, which is the likelihood that a randomly allocated IoT device harvests enough power to enable its operation. We derive an expression for this probability at a random location in terms of harvesting sufficient power for IoT device operation at a given measurement rate. Next, we consider the remote powering o, Ökningen av antalet Internet of Things (IoT)-nätverk har gjort batteri-byte i IoT-enheter alltmer utmanande. Detta problem är särskilt besvärligt i scenarier med ett stort antal IoT-enheter, på platser där IoT-enheter är svåra att komma åt, eller när frekventa batteribyten är nödvändiga. Risken att förlora eller glömma bort vissa IoT-enheter finns också, vilket leder till en risk för farligt kemiskt läckage och elektronikskrot i naturen. Trådlös energiöverföring(eng. wireless power transfer, WPT) via radiofrekvens-signaler erbjuder en alternativ lösning för att strömförsörja dessa enheter. När en trådlösa sändare skickar signaler når mindre än en miljondel av energin till de tilltänkta mottagarna,medan resten absorberas av omgivningen. Denna situation skapar möjligheten att utnyttja befintlig trådlös infrastruktur, såsom basstationer,för att ladda IoT-enheter med WPT-teknik. I denna avhandling fokuserar vi på att analysera genomförbarheten och begränsningarna av batterilös drift av IoT-enheter med radiofrekvens-WPT-teknologi, tillsammans med energi utvinningfrån befintlig trådlös kommunikationsinfrastruktur. Vi utforskar energiförsörjning av IoT-enheter både i inomhus- och utomhusscenarier. Först utforskar vi en utomhusmiljö där en IoT-enhet periodiskt skördar energi från befintliga basstationers signaler och använder den till att sända datapaket relaterade till sensormätningar. Vi analyserar täckningsområdet runten basstation för energiutvinning, vilket visar en avvägning mellan räckvidd och sensormätningens frekvens. Vi jämför WPT-lösningen med batteridrivna teknologier. Därefter analyserar vi täckningssannolikheten i ett fall medmånga basstationer. Detta är sannolikheten att en slumpmässigt placeradIoT-enhet kan skörda tillräckligt med kraft för sin drift. Vi härleder ett uttryck för denna sannolikhet för en given mätningfrekvens. Därefter analyserar vi energiförsörjning till IoT-enheter inuti ett flygplan.Kabelanslutna sensorer adderar vikt och underhållskostnad, QC 20240214

The growth of Internet of Things (IoT) networks has made battery replacement in IoT devices increasingly challenging. This issue is particularly pronounced in scenarios with a large number of IoT devices, in locations where IoT devices are difficult to access, or when frequent replacement is necessary. The risk of losing or forgetting some IoT devices also exists, leading to a risk of hazardous chemical leakage and e-waste in nature. Radio Frequency(RF) wireless power transfer (WPT) offers an alternative solution for powering these devices. Moreover, it has been observed that the receivers absorb less than one-millionth of the transmitter energy while surrounding objects absorb the remainder. This situation opens up the possibility of leveraging existing wireless infrastructures, such as base stations (BSs), to charge IoT devices. In this thesis, we focus on analyzing the feasibility and limitations of battery-less operation of IoT devices using RF WPT technology, along with energy harvesting (EH) from existing wireless communication infrastructure. We explore both indoor and outdoor scenarios for powering IoT devices. Initially, we consider an outdoor environment where an IoT device periodically harvests energy from existing BSs and transmits a data packet related to sensor measurement. We analyze the coverage range of energy harvesting from a BS for powering IoT devices, which shows a tradeoff between the coverage range and the rate of sensor measurements. Additionally, we compare the operational domain in terms of the range and measurement rate for WPT and battery-powered technologies. Furthermore, we consider the coverage probability for a multi-site scenario, which is the likelihood that a randomly allocated IoT device harvests enough power to enable its operation. We derive an expression for this probability at a random location in terms of harvesting sufficient power for IoT device operation at a given measurement rate. Next, we consider the remote powering o, Ökningen av antalet Internet of Things (IoT)-nätverk har gjort batteri-byte i IoT-enheter alltmer utmanande. Detta problem är särskilt besvärligt i scenarier med ett stort antal IoT-enheter, på platser där IoT-enheter är svåra att komma åt, eller när frekventa batteribyten är nödvändiga. Risken att förlora eller glömma bort vissa IoT-enheter finns också, vilket leder till en risk för farligt kemiskt läckage och elektronikskrot i naturen. Trådlös energiöverföring(eng. wireless power transfer, WPT) via radiofrekvens-signaler erbjuder en alternativ lösning för att strömförsörja dessa enheter. När en trådlösa sändare skickar signaler når mindre än en miljondel av energin till de tilltänkta mottagarna,medan resten absorberas av omgivningen. Denna situation skapar möjligheten att utnyttja befintlig trådlös infrastruktur, såsom basstationer,för att ladda IoT-enheter med WPT-teknik. I denna avhandling fokuserar vi på att analysera genomförbarheten och begränsningarna av batterilös drift av IoT-enheter med radiofrekvens-WPT-teknologi, tillsammans med energi utvinningfrån befintlig trådlös kommunikationsinfrastruktur. Vi utforskar energiförsörjning av IoT-enheter både i inomhus- och utomhusscenarier. Först utforskar vi en utomhusmiljö där en IoT-enhet periodiskt skördar energi från befintliga basstationers signaler och använder den till att sända datapaket relaterade till sensormätningar. Vi analyserar täckningsområdet runten basstation för energiutvinning, vilket visar en avvägning mellan räckvidd och sensormätningens frekvens. Vi jämför WPT-lösningen med batteridrivna teknologier. Därefter analyserar vi täckningssannolikheten i ett fall medmånga basstationer. Detta är sannolikheten att en slumpmässigt placeradIoT-enhet kan skörda tillräckligt med kraft för sin drift. Vi härleder ett uttryck för denna sannolikhet för en given mätningfrekvens. Därefter analyserar vi energiförsörjning till IoT-enheter inuti ett flygplan.Kabelanslutna sensorer adderar vikt och underhållskostnad, QC 20240214

The growth of Internet of Things (IoT) networks has made battery replacement in IoT devices increasingly challenging. This issue is particularly pronounced in scenarios with a large number of IoT devices, in locations where IoT devices are difficult to access, or when frequent replacement is necessary. The risk of losing or forgetting some IoT devices also exists, leading to a risk of hazardous chemical leakage and e-waste in nature. Radio Frequency(RF) wireless power transfer (WPT) offers an alternative solution for powering these devices. Moreover, it has been observed that the receivers absorb less than one-millionth of the transmitter energy while surrounding objects absorb the remainder. This situation opens up the possibility of leveraging existing wireless infrastructures, such as base stations (BSs), to charge IoT devices. In this thesis, we focus on analyzing the feasibility and limitations of battery-less operation of IoT devices using RF WPT technology, along with energy harvesting (EH) from existing wireless communication infrastructure. We explore both indoor and outdoor scenarios for powering IoT devices. Initially, we consider an outdoor environment where an IoT device periodically harvests energy from existing BSs and transmits a data packet related to sensor measurement. We analyze the coverage range of energy harvesting from a BS for powering IoT devices, which shows a tradeoff between the coverage range and the rate of sensor measurements. Additionally, we compare the operational domain in terms of the range and measurement rate for WPT and battery-powered technologies. Furthermore, we consider the coverage probability for a multi-site scenario, which is the likelihood that a randomly allocated IoT device harvests enough power to enable its operation. We derive an expression for this probability at a random location in terms of harvesting sufficient power for IoT device operation at a given measurement rate. Next, we consider the remote powering o, Ökningen av antalet Internet of Things (IoT)-nätverk har gjort batteri-byte i IoT-enheter alltmer utmanande. Detta problem är särskilt besvärligt i scenarier med ett stort antal IoT-enheter, på platser där IoT-enheter är svåra att komma åt, eller när frekventa batteribyten är nödvändiga. Risken att förlora eller glömma bort vissa IoT-enheter finns också, vilket leder till en risk för farligt kemiskt läckage och elektronikskrot i naturen. Trådlös energiöverföring(eng. wireless power transfer, WPT) via radiofrekvens-signaler erbjuder en alternativ lösning för att strömförsörja dessa enheter. När en trådlösa sändare skickar signaler når mindre än en miljondel av energin till de tilltänkta mottagarna,medan resten absorberas av omgivningen. Denna situation skapar möjligheten att utnyttja befintlig trådlös infrastruktur, såsom basstationer,för att ladda IoT-enheter med WPT-teknik. I denna avhandling fokuserar vi på att analysera genomförbarheten och begränsningarna av batterilös drift av IoT-enheter med radiofrekvens-WPT-teknologi, tillsammans med energi utvinningfrån befintlig trådlös kommunikationsinfrastruktur. Vi utforskar energiförsörjning av IoT-enheter både i inomhus- och utomhusscenarier. Först utforskar vi en utomhusmiljö där en IoT-enhet periodiskt skördar energi från befintliga basstationers signaler och använder den till att sända datapaket relaterade till sensormätningar. Vi analyserar täckningsområdet runten basstation för energiutvinning, vilket visar en avvägning mellan räckvidd och sensormätningens frekvens. Vi jämför WPT-lösningen med batteridrivna teknologier. Därefter analyserar vi täckningssannolikheten i ett fall medmånga basstationer. Detta är sannolikheten att en slumpmässigt placeradIoT-enhet kan skörda tillräckligt med kraft för sin drift. Vi härleder ett uttryck för denna sannolikhet för en given mätningfrekvens. Därefter analyserar vi energiförsörjning till IoT-enheter inuti ett flygplan.Kabelanslutna sensorer adderar vikt och underhållskostnad, QC 20240214

The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

The booming evolution of portable, wearable electronic devices, wireless sensors, and integrated microelectronics has stimulated the need for miniaturized power supply modules. Energy harvesters, which harness the environmental energy for electricity use, and micro super capacitors (MSCs),known for the small form factor and rapid power delivery, provide energy efficient solutions. Meanwhile, the demand for sustainable development hasdriven the research towards environmental and ecological-friendly energy solutions. In light of this, utilizing paper as a substrate offers a promising avenue due to its sustainability, lightweight nature, disposability, and availability. Integrating energy harvesters and micro super capacitors into on paper micro-power sources holds the potential for ready-to-use smartelectronics, such as biosensors for detection and diagnostics. Nonetheless, the progress of on-paper MSCs is still in its infancy encountering challenges in appropriate material selection, structure, and fabrication design. 2D material MXene and conducting polymer PEDOT:PSS hold promises for on-paper MSCs thanks to their hydrophilic nature and excellent electrochemical properties. In terms of energy harvesting units,hydrovoltaic technologies that generate electricity from water movement offer a sustainable energy solution, while triboelectric nanogenerators (TENGs) harness the ubiquitous mechanical energy in the environment to produce electrical power. Such electric energy can be directly utilized or stored with the assistance of MSCs for later consumption. However, integrating energy harvesting and storage components on paper involves complex material and fabrication requirements. This thesis aims at enhancing the rate capability (thecharge and discharge ability at high rates while maintaining the storage capacity) of on-paper MSCs, advancing the development of hydrovoltaic and TENGs energy harvesters and eventually integrating TENGs and MSCs to a non-paper power supply., Den snabba utvecklingen av mindre, bärbara, elektroniska apparater medtrådlösa sensorer, integrerade kretsar och displayer har tvingat fram ett behov av små strömförsörjningsenheter som kan driva denna typ av elektronikprodukter. En möjlighet är att använda miniatyriserade ”energiskördare” som omvandlar mekanisk, termisk eller annan energi som genereras i omgivningen till elektrisk energi. Exempel påsådan energi som finns i vår närmiljö kan vara solljus, vågrörelse, kroppsrörelse och kroppsvärme. Genom att konstruera t ex piezo- eller triboelektriskageneratorer, som tar upp tryck och rörelse och omvandlar detta till elektrisk spänning, kan man generera en ström som skulle kunna räcka till för att driva en liten elektrisk krets. Funktionen av en sådan strömförsörjningsenhet kan också förbättras genom att addera ett batteri som kan lagra den genererade elektriska energin, t ex genom en liten kondensator med lång tidskonstant, en sk mikrosuperkondensator. Denna avhandling visar olika möjligheter att bygga användbara små generatorer och kraftmoduler som uppfyller de tekniska kraven för effektförsörjning av bärbar elektronik. I avhandling strävas också efter att uppfylla hållbarhetsmålen och att minska miljöbelastningen genom att använda ”gratisenergi” i vår omgivning och även utnyttja material och processer som har minimal negativ påverkan på miljön. Den framtagna tekniken baseras på att trycka elektriska komponenter och kretsar på papper, vilket uppfyller kraven på miljövänlighet och hållbarhet. Produkten kan också göras liten, har låg vikt och är böjlig, vilket gör den väl lämpad för bärbara applikationer. Den blir också billig att tillverka och, genom att miljövänliga material används, kan den slängas eller brännas utan miljöpåverkan, till skillnad från mycket av den elektronik som vi använder idag. Inledningsvis behandlas framtagningen av ett ledande bläck som också har nödvändiga egenskaper för att kunna tryckas på papper. Aktiva substanser ibläcket är 2D-materiale, QC 20240508

Concrete is a widely used material that presents vast opportunities for energy harvesting applications. Among these, thermoelectric concrete shows promising potential for harvesting waste heat generated in urban and industrial environments. However, the development of thermoelectric concrete poses several challenges that need to be addressed, such as the need to accurately account for the intrinsic voltage. This factor is frequently disregarded, but it has a significant impact on the measurement of thermoelectric properties in improving the intrinsically low electrical conductivity and Seebeck coefficient. In this context, this study evaluates the performance of industrially scalable geopolymer-based concrete that incorporates recycled aggregates as low-cost and environmentally friendly additives for thermoelectric energy harvesting applications. The concrete exhibited an intrinsic voltage of 15 mV, and a new test protocol was proposed to exclude its impact on thermoelectric measurements. The geopolymer concrete demonstrated a significantly high Seebeck coefficient of 570 µV/k, surpassing all previously reported values for geopolymer-based materials. Furthermore, it was discovered that the thermoelectric behavior of geopolymer-based concrete is of ionic origin, indicating that further improvements can be made by adjusting the pore solution chemistry. This finding suggests that there is ample opportunity for innovation and optimization in the development of thermoelectric concrete.

A solar tracking system is used to orient solar reflectors, photovoltaic panels, and other solar energy harvesting equipment toward the sun mainly to maximize energy output. The LEESOLA system offers an optimized way to increase the amount of energy produced by exposing the harvesting equipment to the sun’s rays. This project is a crucial step towards a more sustainable future and reducing the reliance of humans on traditional energy sources. The system architecture of the LEESOLA solar tracker consists of a microcontroller-based control unit, an ultra-violet (UV) sensor module, motor drivers and PV panels. The UV sensor module detects the location of the sun and sends signals to the control unit. The control unit then passes signals to the motor drivers to introduce a change in the position of the solar panels. The control unit makes use of a suitable algorithm for keeping track of the location of the sun throughout the day and changes the angle of the PV panels accordingly. The UV sensor module makes use of essential optoelectronic components such as photodiodes or phototransistors to detect the position of the sun accurately. As a measure of eliminating any occurrence of misalignment due to factors such as weather conditions, the system has a built-in feedback mechanism that actively monitors the solar panel’s position and adjusts the motor drivers to correct any misalignment. The proposed system obtained an improvement of about 69.29%, 59.41% and 184.96% mean percentage difference in the measured power readings for morning, afternoon, and evening durations respectively. Therefore, this LEESOLA system provided an all-rounded performance improvement over the limiting static methods.

A solar tracking system is used to orient solar reflectors, photovoltaic panels, and other solar energy harvesting equipment toward the sun mainly to maximize energy output. The LEESOLA system offers an optimized way to increase the amount of energy produced by exposing the harvesting equipment to the sun’s rays. This project is a crucial step towards a more sustainable future and reducing the reliance of humans on traditional energy sources. The system architecture of the LEESOLA solar tracker consists of a microcontroller-based control unit, an ultra-violet (UV) sensor module, motor drivers and PV panels. The UV sensor module detects the location of the sun and sends signals to the control unit. The control unit then passes signals to the motor drivers to introduce a change in the position of the solar panels. The control unit makes use of a suitable algorithm for keeping track of the location of the sun throughout the day and changes the angle of the PV panels accordingly. The UV sensor module makes use of essential optoelectronic components such as photodiodes or phototransistors to detect the position of the sun accurately. As a measure of eliminating any occurrence of misalignment due to factors such as weather conditions, the system has a built-in feedback mechanism that actively monitors the solar panel’s position and adjusts the motor drivers to correct any misalignment. The proposed system obtained an improvement of about 69.29%, 59.41% and 184.96% mean percentage difference in the measured power readings for morning, afternoon, and evening durations respectively. Therefore, this LEESOLA system provided an all-rounded performance improvement over the limiting static methods.

Energy harvesting has gained lots of interest over the past few decades. This study explores the application of energy harvesting in lower limb prosthetic devices. The control system of a lower limb prosthesis includes sensors, wireless systems and other active components which all require battery power. In order to save some of this battery power, reduce weight, and have the devices have a longer runtime, a form of energy regeneration is desired. Therefore the goal of this study is to design and experimentally evaluate an energy harvesting system to power the control system of lower limb prostheses. The final prototype is designed following the process of setting up functional requirements, constraints and wishes. This leads to three derived concepts. After an evaluation against performance criteria and an in-depth evaluation concerning the power output, the compliant spring design is chosen to be worked out further and evaluated with a newly designed vibration shaker table. The relevant findings are laid out in the results. From these findings, interpretations and implications are discussed further, concerning advantages and limitations of the energy harvesters and the experiment. Results from the conducted experiment show a peak power output of 25.8 mW at an input amplitude of 12 mm and a frequency of 9 Hz. A power mass ratio of 0.21W/kg is achieved. The design meets the power demand requirements to power microprocessors and sensors of the control system of a lower limb prosthesis and extends runtime with 15.7%. However it is still important to investigate the power requirements for state of the art lower limb prostheses. Furthermore, it is recommended to improve overall efficiency in future studies, compare the results with state of the art energy harvesters based on vibrations, and execute a gait test for further design validation. The results from this study demonstrate comparable data and present the innovations possible in prosthesis design and the a, Mechanical Engineering

A conceptual shift toward next-generation wearable electronics is driving research into self-powered electronics technologies that can be independently operated without plugging into the grid for external power feeding. Triboelectric nanogenerators (TENGs) are emerging as a key component of self-powered electronics, but a power type mismatch between supply and demand limits their direct implementation into wearable self-powered electronics. Here, a TENG with switchable power mode capability is reported where the charge flow direction is modulated over the course of slow and random mechanical stimuli, with exceptional rectification capabilities as high as approximate to 133, stable outputs over the cycles, and design flexibility in different platforms. Importantly, the remarkable switchable power generation with fabric counter materials illuminates a new path for the smooth integration of flexible TENGs into wearable self-powered electronics. Triboelectric nanogenerators (TENGs) with a convertible rectification feature, in which the direction of the charge flow generated by TENGs is systematically controlled by electrostatic breakdown over the course of slow and random mechanical stimuli, is reported, paving the path for the development of all-in-one nanogenerators and the incorporation of nanogenerators into wearable self-powered electronics in the near future. image

Insufficient power output and poor wearability present significant challenges to the real-world implementation of existing footwear energy harvesters. Herein, we propose a leaf-spring-based motion converter that converts the low-frequency linear motion from footstep activity into the high-speed rotation of the electromagnetic generator and achieves high-performance power output and wearability. The motion converter employs a moderate stiffness leaf spring coupled with bearings to transfer vertical displacement of the heel into horizontal deformation and absorb shock at the footstep touchdown moment. A ratchet clutch is utilized to switch the working modes of the generator between the stance and swing phases. We characterized the dynamic response of the motion converter and developed an analytical model to predict the power output of the system. Furthermore, we fabricated a lightweight and compact prototype and tested it under pseudo and natural walking conditions. The prototype achieves a displacement amplification ratio of up to 2.2 and reduces acceleration amplitude at touchdown by 10.7% compared with walking without the device. At a stride frequency of 1 Hz, our prototype shows an open-circuit voltage of 20 V, short-circuit current of 0.4 A, a peak power of 1.88 W, and a power density of 15.2 mW/cm3, higher than the previously reported footwear energy harvester.

In recent years, a free-rotating disk triboelectric nanogenerator (rTENG) has attracted considerable attention as a promising energy harvester due to its high output energy among many triboelectric nanogenerator (TENG) types. However, the high output of the rTENG is often challenged by air breakdown between the electrodes. To overcome this issue, in this present work, we have developed a triboelectric nanogenerator based on alcohol-soluble nylon technology (AN-rTENG). Compared to the conventional nylon-based triboelectric nanogenerator (CN-rTENG), the AN-rTENG significantly suppresses air breakdown and improves the energy output due to the increased capacity to accommodate charges on the two electrode plates (by changing the filler between the two electrodes). Under identical experimental conditions, the AN-rTENG demonstrates substantial performance enhancements over the CN-rTENG. These include a 25% increase in the AN-rTENG's short-circuit current and a 45.5% increase in its open-circuit voltage. Additionally, the influence of various factors on the performance of the AN-rTENG has been discussed, including the ethanol concentration, the mass fraction of PA66 in the alcohol-soluble nylon solution, the thickness of the alcohol-soluble nylon (ASN) film, and the distance between the stator and rotor. With optimized design, the ASN film thickness is 60 mu m, the stator-rotor distance is 2 mm, and the rotor speed is 4 Hz. the AN-rTENG exhibits a short-circuit current amplitude of 247 mu A, an open-circuit peak voltage amplitude of 27 kV, a transferred charge of 3.6 mu C, and a peak power density of 18.9 W/m(2). The AN-rTENG provides a pathway for promoting the rTENG with its advantages of easy fabrication, high electrical power, and low cost.

Lead-free BiFeO3–BaTiO3 (BF-BT) piezoceramics have sparked considerable interest in recent years due to their high piezoelectric performance and high Curie temperature. In this paper, we show how the addition of highly aligned porosity (between 40 and 60 vol %) improves the piezoelectric performance, sensing, and energy harvesting figures of merit in freeze-cast 0.70BiFeO3–0.30BaTiO3 piezoceramics compared to conventionally processed, nominally dense samples of the same composition. The dense and porous BF-BT ceramics had similar longitudinal piezoelectric coefficients (d33) immediately after poling, yet the dense samples were observed to age faster than those of porous ceramics. After 24 h, for example, the porous samples had significantly higher d33 values ranging from 112 to 124 pC/N, compared to 85 pC/N for the dense samples. Porous samples exhibited 3 and 5 times higher longitudinal piezoelectric voltage coefficient g33 and energy harvesting figure of merit d33g33 than dense samples due to the unexpected increase in d33 and decrease in relative permittivity with porosity. Spontaneous polarization (Ps) and remnant polarization (Pr) decrease as the porosity content increased from 37 to 59 vol %, as expected due to the lower volume of active material; however, normalized polarization values with respect to porosity level showed a slight increase in the porous materials relative to the dense BF-BT. Furthermore, the porous ceramics showed improved temperature-dependent strain–field response compared to the dense. As a result, these porous materials show excellent potential for use in high temperature sensing and harvesting applications.

Growing global energy demands necessitate exploration of sustainable alternatives. This paper investigates the feasibility of a "Foot Step Power Generation System" utilizing piezoelectric technology. Piezoelectric materials convert pressure from footsteps into electricity. A prototype system with 12 sensors in a 1 ft² area was implemented to evaluate the concept. The experiment successfully harnessed mechanical energy from footsteps, demonstrating the potential of this approach for sustainable energy solutions. Furthermore, the possibility of integrating this technology on an individual level, such as in shoes, is explored for future development. However, limitations in static measurements and environmental sensitivity were identified. Further research will focus on optimizing the system for broader deployment in public spaces and for individual applications, contributing to energy efficiency and sustainable practices.

El treball que es presenta a continuació se centra en l'exploració de solucions innovadores en el monitoratge de pacients fora de l'hospital, amb èmfasi en l'autonomia energètica dels dispositius mèdics portables. Es proposa un estudi teòric i pràctic per construir un prototip d'electrocardiògraf alimentat per l'energia de les ones de radiofreqüència. Es revisen tècniques de captació d'energia i s'analitzen les particularitats d’aquestes aplicades a la radiofreqüència. Es realitza un estudi sobre l'electrocardiograma com a diagnòstic mèdic i l'arquitectura d'un electrocardiògraf convencional. La part final aborda la construcció del prototip, incloent la comparació de components, la creació de la placa de circuit imprès i els primers passos en la programació del microcontrolador per verificar el seu funcionament. L'objectiu és desenvolupar una solució que aprofiti l'energia de l'entorn per a dispositius de monitoratge, millorant l'autonomia i la llibertat dels pacients en règim no hospitalari., El trabajo que se presenta a continuación se centra en la exploración de soluciones innovadoras en la monitorización de pacientes fuera del hospital, con énfasis en la autonomía energética de los dispositivos médicos portátiles. Se propone un estudio teórico y práctico para construir un prototipo de electrocardiograma alimentado por la energía de las ondas de radiofrecuencia. Se revisan técnicas de captación de energía y se analizan las particularidades de estas aplicadas a la radiofrecuencia. Se realiza un estudio sobre el electrocardiograma como diagnóstico médico y la arquitectura de un electrocardiograma convencional. La parte final aborda la construcción del prototipo, incluyendo la comparación de componentes, la creación de la placa de circuito impreso y los primeros pasos en la programación del microcontrolador para verificar su funcionamiento. El objetivo es desarrollar una solución que aproveche la energía del entorno para dispositivos de monitorización, mejorando la autonomía y la libertad de los pacientes en régimen no hospitalario., The work presented below focuses on exploring innovative solutions in monitoring patients outside the hospital, with an emphasis on the energy autonomy of portable medical devices. A theoretical and practical study is proposed to build a prototype electrocardiogram powered by the energy of radiofrequency waves. Energy harvesting techniques are reviewed, and the specificities of their application to radiofrequency are analysed. A study is conducted on the electrocardiogram as a medical diagnosis tool and the architecture of a conventional electrocardiogram. The final part addresses the construction of the prototype, including component comparisons, the creation of the printed circuit board, and the initial steps into programming the microcontroller to verify its operation. The objective is to develop a solution that harnesses environmental energy for monitoring devices, enhancing the autonomy and freedom of patients undergoing non-hospital care.

Serious climate changes and energy-related environmental problems are currently critical issues in the world. In order to reduce carbon emissions and save our environment, renewable energy harvesting technologies will serve as a key solution in the near future. Among them, triboelectric nanogenerators (TENGs), which is one of the most promising mechanical energy harvesters by means of contact electrification phenomenon, are explosively developing due to abundant wasting mechanical energy sources and a number of superior advantages in a wide availability and selection of materials, relatively simple device configurations, and low-cost processing. Significant experimental and theoretical efforts have been achieved toward understanding fundamental behaviors and a wide range of demonstrations since its report in 2012. As a result, considerable technological advancement has been exhibited and it advances the timeline of achievement in the proposed roadmap. Now, the technology has reached the stage of prototype development with verification of performance beyond the lab scale environment toward its commercialization. In this review, distinguished authors in the world worked together to summarize the state of the art in theory, materials, devices, systems, circuits, and applications in TENG fields. The great research achievements of researchers in this field around the world over the past decade are expected to play a major role in coming to fruition of unexpectedly accelerated technological advances over the next decade.