%0 Conference Proceedings
%A Alan K Meier
%A Cecilia Aragon
%A Daniel Perry
%A Therese Peffer
%A Marco Pritoni
%A Jessica Granderson
%B Energy Efficiency in Domestic Appliances and Lighting Conference
%C Copenhagen
%D 2011
%G eng
%T Measuring the Usability of Appliance Controls
%8 03/2011
%X <p>A “smart” device will remain efficient only as long as the settings and other parameters allow it to be.<br />Thus, the degree of usability is becoming an element of energy efficiency similar to other physical<br />characteristics. We developed and tested a procedure to quantify the usability of thermostats. The<br />procedure assumes that usability can be represented by a user’s ability to accomplish a set of tasks.<br />Thirty-one subjects were tested in their ability to accomplish six essential tasks on programmable<br />thermostats. The tests revealed a wide variation in the subjects’ ability to accomplish the same task on<br />different thermostats. Thus it was possible to discern thermostats that were more effective than others.<br />We created a metric based on data that are easy to collect and unambiguous that appears to reflect the<br />usability of a task. Metrics from different tasks can be added and an overall usability “score” calculated.<br />This approach, as well as the metric, can be applied to other devices where poor usability may impede<br />energy-saving behaviour.</p>