Forget Cfl's They Dont Work So Good In Extreme Cold Anyway... There's An Easier Way. Led X-mas Lights + A Timer. Cheap, Easy, Infinately Flexible, Uses The Least Amount Of Electricity (even Less Than Cfls) And Led Lights Last A Very Very Long Time.
I Recomend Starting With A Light Sensing Timer That Offers Adjustable Length Of On Time.. This Allows Maximum Flexibility And Efficiency. As The Days Start Getting Shorter Just Add More "on Time" To Your Timer. They Automatically Kick On At Dusk And Will Stay On As Long As Your Program Dictates... Dusk - 2 Hrs, Dusk- 4 Hrs, Etc... All The Way Out To Dusk To Dawn If You Wish. These Are Made For Outdoor Use With X-mas Lights And Are Cheap And Readily Available They Plug Into A Wall Outlet Or Extension Cord And Have A Plug Built Into Them So You Simply Plug Your Lights Into Your Timer, Your Timer Into Your Power Source And Then Set Your Program
You Can Use Standard X-mas Mini Lights (for Outdoor Use) If You Wish But You'll Find Many More Times The Longevity From The Led X-mas Mini Lights Instead
Using Rabbit Hutch Type Pen? No Problem, Since Its A String Of Lights Simply Stapel Them To The Under Side Of The Roof, Or Zip Tie Them To The Upper Edge Of The Wire... Make Multiple Wraps For More Intense Light Or To Use Up The Surplus "string Of Lights" They're Available In Sizes From 12 To 40 Ft. Using An Aviary? Still No Problem They Can Be Stapled To The Top Rail, Or Strung Along It Or Even Stretched Across The Netting Or Roof...