Windows 7 has a new power management debugging option built into powercfg.exe that can be used to expose potential power hogging drivers and configuration issues that could be eating away at your battery life and driving up your power bill.
As the description states, it is best to run while the system is idle, much like the WinSat "Windows Experience Index" process.
Running powercfg -energy, you end up with results like this:
Enabling tracing for 60 seconds...
Observing system behavior...
Analyzing trace data...
Energy efficiency problems were found.
Using the default options, a file called energy-report.html will be created in the current directory from which powercfg.exe execute and gives you a snapshot of your system energy consumption over a 60 second period.
My laptop's report during idle was not particularly interesting, so here is an example of energy-report.html while my system was under light load with the usual devices I have plugged in my docking station. I seem to have many Suspend unfriendly USB devices.