What is gpe27? (interrupts are not being caught?)

I just read

https://www.reddit.com/r/linux/comments/3lfxhf/a_linux_powersaving_tip_for_noobs_like_me/

grep . -r /sys/firmware/acpi/interrupts/

shows that after leaving my computer on for a few hours, the number for gpe27 increases. I'm at 12000 at about one hour of uptime.

I'm extremely happy with the battery life and I'm not planning on disabling anything or trying to get more. I'm just curious to learn more about interrupts and XPS 13. What does gpe27 refer to for the XPS 13? If I understand correctly, the XPS13 is sending a signal (called an "interrupt") that is not being caught?