Joseph Meehan wrote:

I remember one college project was to figure out how long you
needed to turn out a standard the old 4 foot tubes before you would
save money. Factoring in the cost of electricity lamps and the labor
for maintenance to replace them, it turned out to be about 20
minutes. We had a fun statistics class back 35 years ago. The CF's
would be far less. That start up surge is like 1/30 of a second and
is about 10 times or less of the rated lamp consumption.

I just read something recently that said FL lights are best suited to spaces
where the lights will be on for at least thirty minutes, so that seems to
fit.