Power Efficiency Diagnostics Report
Cool little utility built into Windows 7 to survey your computers energy efficiency. Run a command prompt as Administrator and run the following:
powercfg –energy
This will run for a minute and then create a report for your system. The filename and path will be shown when it finishes running. Note that you may need to copy the html file from the \windows\system32\ folder to your desktop (or other folder the user has permissions on) before you can open it.