Event-based and time-triggered energy consumption data acquisition in building automation

Control systems in building automation influence achieved energy efficiency of the buildings. One of the measures that is used by control systems is electric energy usage. The paper deals with the subject of automatic data acquisition of electricity consumption not only for the purpose of accounting the energy consumers, but also for using these data in building control systems in order to achieve better building energy efficiency. Event-based and time-triggered energy consumption data acquisition was taken into account and compared. Accuracy, average data transmission load and possible delays were investigated. Three simple assessment factors (called influence and benefits factors): resolution change factor, average data rate change factor and data transmission density change factor were proposed for evaluation of above parameters. For the purpose of research, dedicated computing method of converting actual electricity meter readings data set to: (1) time triggered data sets with various periods (resampling) and (2) send-on delta data sets with various energy deltas, was also developed.