For anyone else that sees a powercfg.exe running all the time, you might be able to find the process that started it by downloading and running ProcessExplorer from Microsoft's Sysinternals site. It will show you the process tree and you can right click on powercfg.exe, take Properties, and view the full command line on the Image tab.
I did submit a ticket to CrashPlan, but I have not heard anything back yet.