Hello all!

As the subject says, I am looking to see if there is any CFL lights that start at -40. (both the same temperature in Celsius or Fahrenheit). I see some that start at -23C/-10F, but living in Canada, It can get pretty nippy up here at times.

Thanks everyone!

-40 is mighty low. I don't think even cold cathode CFLs spec any lower than -20F. I think you are in LED territory there, as far as something other than incandescent goes.

Rated spec on some silicon power supply components (included the LEDs themselves) inside an LED luminaire might have issues at -40, but if it starts up at all it'll hit a more reasonable operating temp pretty quickly. The color output could appear truly whacked when running outside the specified operating range, even if the thing starts up.

Philips rates most of their LED assemblies for -20°C to +41°C, Cree stops at 0C on the low end for their potlight assemblies, but that's likely more a color-rendering & efficiency issue, not a "will it start up" or "will it smoke" problem.

My guess is that a CCFL would start at -40.

Even if a CCFL started at -40 (and it might not- the electronic switching components for the ballast may not have sufficient gain at that temp- it may self-destruct), the amount of light output would be extremely small until it warmed to a point where there was sufficient mercury vapor to have decent excitation current. The CCFLs I have outdoors take a few 10s of minutes to hit full bright even at -15C, and are a dull, dull, orange concentrated near the electrodes before if finds a knee in the warmup curve. Even a 0C the warmup is a few minutes (but only a few minutes.)