As the use of computers has grown, so too has concern about the amount of power that they consume. Data centers, for example, are limited in scalability as they struggle with soaring energy costs as many large companies rely on fast, reliable, and round-the-clock computing services. On large-scale computing clusters, like data centers, even a small drop in power consumption can have large effects. Across computing contexts, reducing power consumed by computers has become a major focus. In this paper, we present a new approach and tool for mapping software design to power consumption and describe how such mappings can provide software designers and developers useful information about the power behavior of the software they are developing. The goal is for software engineers to use this information in designing and developing more energy efficient solutions. © 2012 IEEE.