I'm a single dude, living alone, and was billed for 1400kWh last month! lol but I'm on the extreme end, my place is 100% electric, so all cooking I do other than grilling outside requires electricity, same with clothes dryer, water heater, etc. Also furnace but right now it's still AC season (or open windows). And I make a point to try and save energy!
But seriously, I know where my power draw is: computer currently left on all the time so I can I work on things remotely; and, a server rack with two servers and various network equipment. Also, it's a 40+ year old AC and separate equally as old electric furnace. That will be replaced with a heat pump in the near future. But still, it looks like my homelab alone may account for about 250 kWh alone. lol
More often than not, my AC never gets a break in the summer, even trying to keep it to, say, 74-76F when I'm home, and about 80F when away.