I experienced the high fan issue once. I restarted the device and have not seen this again. Your experience with a restart of the Windows Explorer process is interesting. I just restarted the Windows Explorer process and put the SP4 to sleep. I'll let
it sleep for an hour and then run the sleep study process. I'll post the results when that is complete.
I restarted the Windows Explorer process and put the SP4 to sleep. The sleep report for a 1:23:05 duration has a 5 percent of battery (1,837 mWh) energy change. The two offenders were the Intel HD Graphics (15%) and the CPU C0 Time (11%). This offenders
are consistent with prior sleep periods. This seems consistent with prior energy changes for equivalent periods of time.
However, the power meter reports a 9% loss during this time and 9 hours which now changed to 6 hours remaining. I had attempted to calibrate this yesterday by running the device battery down, and then recharging to 100 percent, but I don't trust that this
is accurate. That being said, the 5% energy change during sleep would mean that the battery would run down fully after 30 hours of continuous sleep. That's not acceptable. My Android 4.4 tablet can sleep for two weeks with less than 2 percent battery drain.