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From: myers@hpfcdj.HP.COM (Bob Myers)
Newsgroups: comp.sys.hp
Subject: Re: Monitors and the environment (sort of)
Message-ID: <17330024@hpfcdj.HP.COM>
Date: 14 Nov 90 18:21:15 GMT
References: <101950167@hpcvlx.cv.hp.com>
Organization: Hewlett Packard -- Fort Collins, CO
Lines: 40

>    1.	Leaving an HP (Sony) monitor and conusming electricity,
>    2.  Cycling the power and incurring the start-up stress on the
>	monitor?


Let's assume you're using the 16" Sonys, which are the least power-hungry.
The specs say they consume about 300 watts, so in one hour you've spent
0.3 kWh on your monitor: that's

	- 7.2 kWh per day,
	- 50.4 kWh per week, or
	- 2620.8 kWh per year.

Now, what does a kilowatt-hour cost in your area, and how does the stress
affect the monitor's AFR?  Let's pick an electric rate out of the air, and
say that a kWh of electricity costs you $0.15.  (I instantly expect tons of
responses, saying "that's way too LOW!" AND "that's way too HIGH!"  These
will all be cheerfully ignored.)  If that's what you pay for electricity,
then you would pay $393.12 to leave your monitor on 24 hours a day for a year.
That seems like a bit much to pay so that you NEVER stress your monitor
with a power cycle.  Certainly, the thermal cycling, etc., associated with 
the power cycling will degrade the reliability to some degree, but my
experience (from a past life as the engineer responsible for these monitors - 
and note that I'm speaking for MYSELF here, NOT for Hewlett-Packard) is that 
too much worrying about this just isn't worth it.

I'd suggest that you leave it on during the day, but feel free to turn the
thing off at night.  (BTW, you DON'T have to power down the system to power
down the monitor; the CPU will hum merrily along, even though nothing is
being done with all of the video that it's putting out.)  This has the
added benefit of running the built-in degausser every so often, so that you
catch magnetic (purity) problems before they become too serious for the
built-in coil to handle.  Also, the ecology will thank you, as that's 300W less
heat to worry about, and 300W that doesn't have to be generated for X hours
that you're not using the monitor.


Bob Myers  KC0EW   HP Graphics Tech. Div.|  Opinions expressed here are not
                   Ft. Collins, Colorado |  those of my employer or any other
myers@fc.hp.com                          |  sentient life-form on this planet.