Should I turn off my Mac Pro nightly?

This is one of the longest running debates in computer history. Unix operating systems benefit from self cleanup which Anacron or Macjanitor can do for Mac OS X, and that is best run when the computer is not in Energy Saver but is not in use while on.
Power supplies give brief surges everytime you turn on.
Yet moving parts wear down machines too.
PRAM batteries drain quicker if machine is unplugged.
Unplugged machines from power, phone and internet are the only ones immune from lightning strike.
Peripherals have to be unplugged too from those sources to secure that immunity.
Plugging and unplugging can wear down wires too.
Which side effect wears down a machine sooner is a matter of luck.

wasted equipment ___
maybe the worst thing about shutting off computers daily is the thermal gradient. Apple even recommends waiting ten minutes before opening the side panel so that the cooler air doesn't suddenly rush over the memory modules. It isnt the cooler air thats a problem but the change in temperature.

exactly how this Tº change affects the metal platters in a hard drive that spins up and down and up and down, and how much the Tº change contributes to the eventual failure of the drive is like a black box. But its a definate factor.

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wasted time ___
i would be curious though, how many studio and schools like the ones you're involved in, are just tired of wasting time setting up multiple machines, and their respective workloads. How many operators too, waste time trying to get their setup all set up, the way they like it (and find efficient), and prefer to just leave it the way it is. Maybe some institutions want to have remote access at night, or weekends.

i know when i have to reboot, it takes me a half hour to set everything up again.

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wasted electricity ___
on the other hand, the carbon footprint of idling computers worldwide is terrible. Mine draws 200W while idling (which it never does though). Imagine a million computers drawing 200W each. Ten, fifty . . .

i know of an energy producing plant where the employees are fined for leaving their computer or lights on at the end of the day.

I turn my TV off when I won't be watching it for a period of time.


... just saying ....

See [Sleeping your Mac vs. Powering it Down|http://web.me.com/pondini/AppleTips/Sleep.html].

A little off topic but you do know that your TV's and monitors are drawing electricity even when they are turned off? We put power bars on all out big energy eaters (except the fridge) and the drop in my electric bill was astounding.