Originally Posted by
steelbikeguy
for fun(?), or at least some education, you can put your lights in the fridge or freezer, and see how long they run. Let them sit in there for an hour or two before beginning the test, in order to allow the internal parts to fully cool off.
Steve in Peoria (thermal tests were a routine part of designing electronics for me back in the old days)
Rather than using a freezer and having to open it repeatedly, it would make a lot more sense to put everything in the backyard and point the light at one of the windows to know how long it lasted.