This paper evaluates whether the U.S. electricity sector is directed away from carbon-intensive technological lock-in, and which factors are contributing, or have potential to contribute, to a possible reorientation of the industry. With the application of a historical analysis of the electricity sector from the late nineteenth century through current day, this analysis finds that, although the industry still relies primarily on carbon-intensive fossil fuel operations, several recent trends indicate that the industry is becoming less carbon intensive, smaller in generation system scale, and more sustainable in operations. Crucial drivers-firm level interactions with technological change, industry leadership and market structure, government intervention and policy momentum, and citizen involvement and behavior patterns-that have traditionally shaped the structure, scale, and environmental footprint of the industry, have also played a prominent role in recent transformations. These results indicate that triggering or extraordinary events may not be necessary to initiate an escape from carbon lock-in in the electricity sector. Complete escape is not yet definitive, however, and it remains to be seen whether the industry is able to transform entirely before any significant climate change disturbances occur. (C) 2010 Elsevier Ltd. All rights reserved.