Programmable thermostats allow Energy3D to study the effects of human behavior on home energy use

Figure 1

Energy3D Version 5.1 has incorporated a new feature: programmable thermostats (Figure 1). This allows users to add a programmable thermostat to each building in the design. Such a thermostat allows building researchers to model the occupants' schedules and thermal comfort preferences, making it possible to include a human dimension into building simulation.

Figure 2

Figure 2 shows the hourly heating cost of a house on January 1st when the thermostat temperature is set to be 18, 19, 20, 21, and 22 °C. Obviously, the higher temperature you set, the higher the cost will be. Notice, however, that the hourly heating cost might be close to zero around noon because the solar energy alone might be enough to provide the heating (it depends on the size of the house, the size of the windows, and the locations of the windows).

Figure3

The thermostat has a graphical user interface that can be used to set the temperature of a building by hour, week, and month (Figure 3). This flexible user interface can adjust the temperature of a thermostat in four different ways:

• Drag "All" button up or down to increase or decrease the temperatures in all the hours of all the days in a week of the selected month. 
• Drag the hour button up or down to increase or decrease the temperatures in the selected hour of all the days in a week of the selected month.
• Drag a gray temperature button on the right up or down to increase or decrease the temperatures in all the hours of the selected day;
• Drag any temperature button up or down to increase or decrease the temperature in the selected hour of the selected day.

In the future, we plan to extend this feature so that Energy3D can model "smart" thermostats such as the Nest Learning Thermostat, which can adapt to the occupants' specific needs and schedules.