Power Quality in Energy Efficient Buildings – a Case Study

Energy-efficient buildings are increasingly equipped with modern automation and control systems that enable significant energy savings by providing energy in the exact place and time of the demand. Moreover, high-performance LED light sources are used as interior lighting. Since the computers, automation system controllers and LED light sources require a lower voltage than the mains voltage, the buildings use a large number of power electronic converters adjusting the power supply conditions for the devices being serviced. Operation of this type of strongly non-linear receivers leads to an increase in transmission losses of electrical energy related to reactive power flow and generation of higher harmonics. Striving to reduce energy consumption in buildings leads to increasing use of these devices, which in consequence will aggravate the problem of insufficient quality of electricity. The paper discusses the provisions of standards for the quality of electricity. The paper presents the results of research on the quality of electricity in the Malopolska Laboratory of Energy Efficient Building – an experimental building equipped with a building automation and control system.