Building energy management systems in building’s retrofit using power lines

The aim of the specific paper is the analysis of the efficiencyof power lines as a communication media for Building Energy Management Systems. The reason behindthis scope is the ability of power lines to be installedin existing buildings without extra wiring.Building Energy Management Systems (BEMS) constitutea part of automation systems. BEMS implement control the indoor environmental parameters while minimizingenergy consumption. This work aims to analyze the ability of installing Building Energy Management Systems (BEMS) in any building while simultaneously improve the energy efficiency and the indoor comfort.The easiest and most economic way to construct a BEMS in an existing building is to use the existing technologiesof the building. These are power lines and Local Area Networks (LANs). Another way to develop and implement BEMS is radio frequencies (RF). These technologiescan be used to existing buildings because they need no wiring and the installation cost is very small.Before choosing the devices that will formulate the BEMS, the parameters that affect the indoor conditions must be determined. Those are thermal comfort, visual comfort, indoor air quality and acoustic comfort.In order to check the efficiency of communication protocolsthat use power lines as a mean to communicate, a test installation is implemented in laboratory. This installation is performed via two development kits: the Power Line Development Support Kit (PL DSK) and Mini Evaluation Kit (Mini EVK). The test included a temperature sensor as a controlled variable and a decentralisedheating control system with a central heating unit for the control signal.The results of the testing as well as specifications for installation in existing buildings are described focusing on disseminating such technologies in meeting the continuouslyincreasing energy demands of the buildings in Crete, Greece.