heat during winter ect

hi i’m going to use a ceramic heat emitter during winter for my bd as it will get quite cold where i am (i think) it’s my first winter having her. its still summer currently but im just thinking ahead. everywhere i read says to have the non light one at night and they need the light bulb for day to mimic the sun. she has the now for just the day and night lights are off. does that mean i now have to have 2 domes for winter for each bulb? or what cause it’s confusing me thank you!