Flutterby™! : Power consumption 2001-02-20 00:13:46+00

Power consumption

2001-02-20 00:13:46+00 by Dan Lyke 8 comments

My house has a full-time server. Beyond the obvious stuff you'd want a server to handle, it gives me a way to get to my data from anywhere and handles automated backups from the office and the web server. Especially in light of the current power crisis I've felt pretty guilty about it and keep talking about ways to build an ultra-low power box running an ARM chip or somesuch. Well, I did some searching about today, and a few sources claim an idle Celeron 533 draws about 1.5 watts, so short of smart fans and maybe some intelligence about drive power-downs (I don't, right now, because I've lost too many drives prematurely that way) I'd be much better off spending that money I'd blow on embedded hardware on smarter lighting strategies.

Well, that's the CHIP, not the system. The motherboard draws current on idle, as do other components; the power supply itself burns quite a bit of energy doing its voltage regulation, even when the system is idle. I'd say that a system on standby would draw at least 20 watts. That's about 15 KwH per month. I'm guessing $7 or so extra on your electric bill, per machine, given your high electric rates. So yeah, building an ultra-low power box is an interesting idea, though you could do it with an X86-instruction-compatible chip rather than an ARM.

I wouldn't feel guilty about it, though; it's not YOUR fault the local government thought electricity came out of the socket in the wall and the power companies were just extortionists.

Actually, those measurements appear to be a full motherboard with VIA chipset and 128Mb DRAM.

And while it's not my fault that the power companies have maneuvered themselves into a corner and are asking the state government to bail them out, electricity consumption in the US is pretty damned profligate, and even though these power plants are just spewing their pollution into Nevada and points downwind of us they do still have an impact.

Put a timer on your hot water heater. Mine comes on for two hours in the morning and two hours in the evening. Result: on 4 hours per day. Off 20 hours per day. Should last for decades then? So turn off the hot water heater and you can load up on ram! P.S. why does auto-powering down the hard drive cause failures?

There are stresses involved in starting the motor and bringing the spindle up to speed that are harder on the bearings than continual running at a steady speed. You also run into a problem with the bearings supporing the weight of the spindle while not in motion.

Oh, and regarding your hot water heater, if you have hot water, why is there a need to heat it? :-)

Actually, the right thing to do hot-water wise is probably to just install a 2.5 gallon/minute flash heater. Unfortunately I can't see making that investment 'til I decide to buy a place.

What Larry said about hard drive failures. When my server had the hard drive powering up once every two hours or so (when the server checked the machines on the 'net for mail and such) a hard disk lasted about 9 months. Took two of those to realize that that wasn't a good idea.

Oh yeah, it was running under my Clary, and the other drive on that server that was older technology and wasn't getting powered up and down all the time is still running today. Starting and stopping is what kills hard drives.

And yes, spending money on a good UPS comes back to you at least fivefold over the life of the UPS in terms of equipment failure.

Warning: Those little flash heaters have one problem; the pipes wear out in five years or so, and when they do, they flood your house giving you no notice. It's more worthwhile just getting a superinsulated water heater, or putting a fiberglas jacket on your current heater.