Well, mr_X here i have to talk, this is my master lol...
Doesn't matter about the watts of a lampsthe t5 are the new options but before was t8 and now the is coldcathote.
Watts mean power and in this case consuption.
Incandecent of a 60w and a florecent of a 20w and now a coldcathote of 15 you...