When we first started getting heavy into mounting projectors we looked at
the cost of running the projector (electricity and bulb). I don't have the
exact figures in front of me, but on an individual basis the costs are
hardly worth mentioning.
It took more in payroll to do the math, maybe 14 cents in an hour's use
(mostly bulb, some electricity). Even when you multiply that by the number
of projectors we have any given hour's use is only a rounding error in a
We did ask people to shut them off when not in use, but not all of them have.
Some have said, the benefit of having them running is the instantaneous
availability, instead of having the wait the couple of mins to let the unit
Skip ahead a few years, now the economy is in the toiley, and (for us
anyway) enrollment is down, budget is frozen.
The problem is that electricity costs happen over time, but that $400 bulb
replacement happens all at once. If the bulbs were to all fail the same
year, we would be looking at $11k. Fortunately this is not our situation,
and most will run for 6+ years at the current consumption rates.
We have a least one heavy user though, who has gotten 3 years out of a bulb
that could have lasted 4 years with judicious use.
At the same time, we would not want to discourage people from actually using
the equipment ...
Looking ahead, I may be more proactive about this, and am just wondering if
anyone has had (or heard of) issue with a bulb that has been turned off/on
multiple times during the day (preps, lunch, etc).