Residual power consumption of your Nerd Equipment(TM)


I am wondering how much residual energy you use for your nerd equipment. As my graphs show I consume about 30 W for various gadgets: A cable modem, a WLAN router, a switch and my (brandnew) QNAP TS219P NAS server. I was using an old PC as a home server years ago, but the energy consumption of this beast was just to high. The new QNAP server runs Debian and runs several services. For example, the Fluksobot runs on it, and my continuous temperature monitoring.

Although I am pretty happy with my current setup: Do you see any room for improvement? How does your setup look like?


drowe67's picture

Hello Mathias,

I also consume 30W for my basic office IT - DSL modem/WRT54G/switch plus an IP04 IP-PBX which I maintain so have to keep running.

However 30W adds up as this stuff is usually on 24 hours/day.

I also threw out an old x86 server due to power requirements. What I miss though is print sharing and perhaps a small file server. I really want a no-fuss x86 type Linux box as a server but with the power consumption on an embedded box. The Sheeva plug-in servers might be an option.

I can't help thinking this could all be improved. Would be interesting to compare the power consumption at the DC port top the AC. I suspect the little power supplies are all inefficient. Perhaps powering all of the 12V devices from one power supply might be better.

- David

gonium's picture

Hi David,

the TS-219P and the Sheevaplug both use the same Kirkwood SoC. I opted for the TS-219P because of the SATA connection to the harddisks, and the additional USB ports. It is my print and file server, in addition to running some pet projects. Both systems are (almost) fully supported by Debian:

I have not been running into any trouble with this so far. The TS-219P feels like a Pentium-III - I fully encrypt my filesystems which costs some performance. The support for the Kirkwood crypto hardware is on the way, though.

So, to sum it up: I don't see any reason for me to go back to an x86 machine. An Atom-based system would require a lot of tweaking to optimize the power consumption, and it would cost at least as much as the TS-219P. One showstopper would be if you need Java, it's not available for ARM. But anything else works quite well.


PS: I really like your electric car conversion project! I was thinking of doing the same here in Germany, but the regulations are really tough - I don't think it is feasible here.

drowe67's picture

Thanks Mathias - the TS-219P sounds like exactly what I need. By "x86 machine" I meant something like the TS-219P that runs a full Linux distro - something that feels like a Pentium 3 as your say.

I am used to messing around with small embedded devices running uClinux or OpenWRT which aren't quite as easy to use as a box with a full Linux distro support. Although I have thought about using an IP08 as a print server as it has a USB port. The IP0X devices are very low power - about 1W when operating without any analog telephony ports.

Re the Electric Car I have just installed some Lithium batteries, will blog on that soon. Charging it does consume a lot of power, but less that what we make from our PV solar.

Actually the legal side of the conversion was stressful here too (engineering reports, thorough inspection by people who didn't understand EVs), but I made it through eventually.



gonium's picture

Hi David,

if you go for the TS-219P I have one additional remark: I chose two Western Digital Green Caviar 1.5TB drives (WD15EADS) for it. I wanted big storage, so I had to choose 3.5" drives. The Green Caviar series is designed to be power-efficient. Part of the savings are achieved by parking the heads after only a few seconds of idle time.

For a NAS device, idle is more or less the default state. This lead to a very quick increase of the load cycle count. I would have reached the maximum load cycle count within four months. I was able to switch the head parking feature of using "WDIDLE3", a small semi-official tool of Western Digital.

So, to sum it up, the WD15EADS works quite well, but it's not a hassle-free experience.


egraaf's picture

I guess you will find my setup rather huge.

I use an Athlon based server that uses about 65W, and a Fritzbox, probably 10W, a small ethernet switch, maybe 5W. The other nightly use is a hard disk recorder for TV, fridge, freezer, central heating pump, and it seems the stair lift uses about 20W all the time.

The total averages out to about 160W.

ghostgum's picture

My problem with measurement is the number of standby loads with poor power factor or non sinusoidal current. If you use an appliance power meter (power-mate lite), you can't simply add the real or apparent power to get the total load. The central heater is 3W and 30VA on standby!

Baseload for the house is about 125VA. However the actual load is more like 250VA due to a freezer that runs about 90% of the time, and may die at any time. Replacement payback time for a combined fridge/freezer would be about 5 years, but we need to change some kitchen cabinets to fit the likely replacement fridge which is yet more cost.

Computer+MFP on standby are about 20W, Data cabinet (modem, router, low power PC, doorbell, ventilation fan) about 25W. PVR 20W. The rest is probably about 30W and 60VA.

Our laundry has a hydronic radiator panel for drying clothes. I improved this by mounting two muffin fans in a temporary cardboard structure under the radiator panel. This greatly speeds up the drying process. What wasn't as expected was that it also greatly speeds up drying when the heater is not on. 5W of fan and some clothes lines across the laundry are much more efficient less than a tumble dryer. Now I need to get around the replacing the temporary cardboard before the 3rd winter.

dougpurd's picture

I have security cameras, access control and alarm systems along with a small nas adsl modem and router, I have installed a single switch mode power supply to run everything and am slowly working out if it its cheaper than the separate plug packs or not....I am leaking about 150W somewhere and so far have not found it which is frustrating to say the least.

I have power switches installed for all our appliances (even the oven) so everything that can gets turned off completely.

The main reason I got rid of all the plug packs was the fire risk some of them run quite warm and I have been told plug packs in a plug board gathering dust contribute to a number of house fires.

tinestijn's picture

I recently replaced my dommel bbox with a fritzbox 7390. (required some hacking to get the password out)

MOre futures, less power and a lot of power-management options...
I even can add a hard-drive to it so I could use it as a basic file-server.

I added 'lights-out to my windows-home server (custom build system with atom CPU).
Now I only need to upgrade my linux-box with a tickless kernel. The hardware-cost for an ssd and atom-based mainboard just don't weight up with the energy saving.

I'll also gona buy some timer-switches to power-on during weekends/evenings and poweroff at night-time for the the telenet//cable devices and my 12-port switch

=> that rises a question: How long does the fluksometer can hold measurements without internet access?

icarus75's picture

The Fluksometer will buffer measurements in RAM when it cannot report its readings to the Flukso server. Once it can connect again, the whole buffer will be flushed to the server. There's an aging algorithm in the daemon which mimics the rrd behaviour. So the amount of buffered data will only increase O(log(t)) with time (t).

Please note that the sensor board will keep track of the counter value at all times. So even if a power failure were to occur when the FLM is offline, you'd only lose some granularity of the data. The total consumption however would still be correct. This case will manifest itself on the graph by a non-zero flatline equal to the average consumption during the inteval for which data loss occurred.

petur's picture

My 'IT department' seems to be using 90W, this includes the telenet modem + signal amp + switch, my own router + switch, a TS-439 NAS with 3 disks and the base station of my IP phone.
Now that I see the usage (I'm using flukso inputs to measure subcircuits), I'm considering changing the NAS to a TS-119-II with SSD for the stuff that must run 24/7 (squeezebox server, mail server and some webservices), and only boot the TS-439 when backups are due.

Did anybody from Belgium measure how much the telenet equipment uses? Not that I can kill it at night as even my telephone uses it :)