A generic user interface for energy management in smart homes

Building operating systems play an important role in monitoring energy consumption of devices and improving energy efficiency in household buildings. From this arises a need for a preferably flexible and full-featured user interface to visualize the energy data in the building and allow residents to collect and realize various needs and preferences to the system. This article introduces a generic user interface for building operating systems which is presented from aspects of design, implementation and evaluation. To ensure the user interface can be flexibly adapted to various types of buildings, we design a series of generic data models which are independent of any building operating system. Besides, three roles with different permissions and a number of functional components of the user interface are also introduced in the article. Based on the design, a prototype of such a generic user interface named Building Operating System User Interface (BOS UI) has been implemented to operate the Energy Smart Home Lab (ESHL) at the Karlsruhe Institute of Technology (KIT). We evaluate the design, functionality and usability of the BOS UI qualitatively and quantitatively. The evaluation results show that the BOS UI meets a set of desired requirements (except for system configuration) for a generic user interface of building operating systems. Besides this, the evaluation experiments yielded very positive feedback in many aspects including improvement of energy efficiency and user experience. More than 90% of the test users agreed that the BOS UI provided them with enough information and functionalities that they would need in their daily lives and it can help them to save money. Furthermore, the mean score of the System Usability Scale (SUS) is 79.0, which indicates a good usability. The experiments prove that the user interface is still easy to use, despite abundant features are integrated into the system.