Full Enclosures vs Racks

[Trackstrong83]

are there any ways to increase the ambient temperature for colder climates (besides using an actual space heater or upping your PG&E bill)??

My area gets kinda cold over the winter, and my folks try and save as much money as possible with the utilities. Sometimes it gets down to 50F in our house during the winter. I can remedy this problem in my tank by using a heat lamp, but what about in a rack??

What I did to control heat was move my rack into my closet and use a space heater and constantly keep 1 door of my closet shut. That way I only heat a smalle area instead of an entire room, cause I like it cold when I sleep.