How are you determining this "7 mile drop"? If it's a change in the GOM, well, there's viewtopic.php?p=271853#p271853
I can only guess you're using auto and/or have the AC, heater or defrost on. I almost never use auto.
Supersleeper wrote:USB fans are in the kilowatts range and should be much more efficient.
Kilowatts? I don't even have any floor standing or box fans that draw 1 kW. That's nuts.
USB power is often only 5 volts at 1 amp to maybe 2.4 amps --> 5 watts to 12 watts. Some USB AC adapters can't even put out 1 amp at 5 volts.