Wireless Transmission in Ventilation (HVAC) Ducts for the Internet of Things and Smarter Buildings: Proof of Concept and Specific AntennaDesign

International audienceWe present here a preliminary study of wireless transmissions using the ventilation metallic ducts as waveguides. Starting from the waveguide theory, we deeply study in simulation the actual attenuation encountered by radiowaves in such a specific medium. This kind of wireless link appears to be really efficient, and therefore highly promising to implement Internet of Things (IoT) in old buildings to make them smarter. This paper also expresses a very simple empirical model in order to ease dimensioning a wireless network in such conditions and a specific antenna design enabling both good performance and high robustness to the influence of the environment

DEVELOPMENT OF A WIRELESS SIGNAL ACQUISITION SYSTEM FROM SENSORS FOR COMFORT AND ENERGY QUALITY

AbstractThe acquisition of wireless signals from sensors represents a variety of advantages over cable communication systems. This work presents a ZigBee-based signal acquisition system that takes advantage of its features to make a flexible system that can be used in different fields without the necessary use of a PC since a touchscreen and a microcontroller is used. The system is implemented in a building to monitor all the physical variables that are referred for the comfort of people, such as luminosity, temperature, humidity, gas concentration, smoke, human presence, glass breakage among others. The measure of these variables also could contribute to define or activate some extra-functions of the system, for example, alarms in case of fire presence. The system stores information of all sensors of all the network created in a Micro SD and uses it to make plots, also it is possible to visualize real-time readings.Keywords: Touchscreen, wireless sensor network (WSN), ZigBee.DESARROLLO DE UN SISTEMA DE ADQUISICIÓN DE SEÑALES INALÁMBRICAS A PARTIR DE SENSORES PARA COMODIDAD Y CALIDAD ENERGÉTICAResumenLa adquisición de señales inalámbricas de sensores representa una variedad de ventajas sobre los sistemas de comunicación por cable. Este trabajo presenta un sistema de adquisición de señales basado en antenas ZigBee que aprovecha sus características para hacer un sistema flexible que puede ser utilizado en diferentes campos sin el uso necesario de una PC ya que se utiliza una pantalla táctil y un microcontrolador. El sistema es implementado en un edificio para monitorear todas las variables físicas que se refieren a la comodidad de las personas, tales como luminosidad, temperatura, humedad, concentración de gas, humo, presencia humana, rotura de vidrios, entre otros. La medición de estas variables también es utilizada para activar algunas funciones extras del sistema, por ejemplo, alarmas en caso de presencia de fuego. El sistema almacena información de todos los sensores de toda la red creada en una Micro SD y crea gráficos históricos de dichas variables, además, es posible visualizar lecturas en tiempo real.Palabras claves: Pantalla táctil, red de sensores inalámbrica, ZigBee

Financially Stimulating Local Economies by Exploiting Communities’ Microgrids: Power Trading and Hybrid Techno-Economic (HTE) Model

This paper thoroughly considers the potential of installing microgrids (MGs) in communities that suffer from the economic crisis in order to financially stimulate their local economies. Exploiting the state-of-the-art evolutions in the fields of the MG technology, the Hybrid Techno-Economic (HTE) model is proposed as a suitable techno-economic tool for assessing the power generation/consumption behaviour and the financial performance of these communities’ MGs.The contribution of this paper is four-fold. First, the HTE model is presented. HTE model describes a theoretical analysis that is suitable for studying community’s MGs. Appropriately concatenating one well-validated technical module and one new economic module, the HTE model quickly and conveniently reveals the power generation/consumption and economic profile of community’s MGs. Second, HTE model is integrated through an extended portfolio of power and financial metrics. The applied metrics study the influence of generation and consumption power changes on community’s MGs. The validity and the efficiency of the HTE model are examined with respect to these power changes while the impact of these changes on the power and cash flows of community’s MGs are assessed. Third, a cost-benefit analysis of the operation of community’s MGs accompanied with a financial stability analysis is also demonstrated. The main outcome of these analyses is the daily total benefit (TB) of community’s MGs with its respective financial bounds. Fourth, the contribution of the energy arbitrage and the power production mix among available power sources of community’s MGs to the daily TB is investigated.Apart from promoting the ecological awareness, this paper tries to become a catching argument for the communities in order to exploit the community’s MGs.Citation: Lazaropoulos, A. G., and Lazaropoulos, P. (2015). Financially Stimulating Local Economies by Exploiting Communities’ Microgrids: Power Trading and Hybrid Techno-Economic (HTE) Model. Trends in Renewable Energy, 1(3), 131-184. DOI: 10.17737/tre.2015.1.3.001

A Scalable and Secure System Architecture for Smart Buildings

Recent years has seen profound changes in building technologies both in Europe and worldwide. With the emergence of Smart Grid and Smart City concepts, the Smart Building has attracted considerable attention and rapid development. The introduction of novel information and communication technologies (ICT) enables an optimized resource utilization while improving the building performance and occupants' satisfaction over a broad spectrum of operations. However, literature and industry have drawn attention to certain barriers and challenges that inhibit its universal adoption. The Smart Building is a cyber-physical system, which as a whole is more than the sum of its parts. The heterogeneous combination of systems, processes, and practices requires a multidisciplinary research. This work proposes and validates a systems engineering approach to the investigation of the identified challenges and the development of a viable architecture for the future Smart Building. Firstly, a data model for the building management system (BMS) enables a semantic abstraction of both the ICT and the building construction. A high-level application programming interface (API) facilitates the creation of generic management algorithms and external applications, independent from each Smart Building instance, promoting the intelligence portability and lowering the cost. Moreover, the proposed architecture ensures the scalability regardless of the occupant activities and the complexity of the optimization algorithms. Secondly, a real-time message-oriented middleware, as a distributed embedded architecture within the building, empowers the interoperability of the ICT devices and networks and their integration into the BMS. The middleware scales to any building construction regardless of the devices' performance and connectivity limitations, while a secure architecture ensures the integrity of data and operations. An extensive performance and energy efficiency study validates the proposed design. A "building-in-the-loop" emulation system, based on discrete-event simulation, virtualizes the Smart Building elements (e.g., loads, storage, generation, sensors, actuators, users, etc.). The high integration with the message-oriented middleware keeps the BMS agnostic to the virtual nature of the emulated instances. Its cooperative multitasking and immerse parallelism allow the concurrent emulation of hundreds of elements in real time. The virtualization facilitates the development of energy management strategies and financial viability studies on the exact building and occupant activities without a prior investment in the necessary infrastructure. This work concludes with a holistic system evaluation using a case study of a university building as a practical retrofitting estimation. It illustrates the system deployment, and highlights how a currently under development energy management system utilizes the BMS and its data analytics for demand-side management applications