Power consumption of routers

I have several routers with different power consumption (measured with deactivated wlan):

GL-iNet MT300A       = 1.0 W
TP-Link Archer C7 V5 = 3.5 W
RPi4B                = 4.0 W
Linksys WRT1900ACS   = 9.5 W

The costs for 1 kWh at my location is 0.30 €. So using the MT300A causes yearly cost of 24 hours x 365 days => 8,760 hours x 0.30 € = 2.63 €/year. The WRT1900ACS causes yearly cost of 24.97 €.

So my question is: can I control the power consumption of a router running with openwrt by selecting special parameters?

I fiddled with the rpi4b by selecting different frequencies and governors. Are there similar parameters for other routers (specially the WRT1900ACS)?

Broadly yes... specifically not really...

  • You can disable wifi ( 30-50%? )
  • Not use usb ( 15-20%? )
  • Run absolute minimal processes ( 5-55%? over 100% time )
  • Some devices set low frequency scaling ( with upper performance hit )

Put simple, running the absolute minimum services and lower scaling might get you to ( very roughly ) perma 35-55% savings maximum...

Which is kinda significant over two years... ( 100-200AUD$ / 50-120$US worth? ) but in the context of a whole household it's not that much...

Specifically, as you note: some devices either by poor design, power supply inefficiency or other... just chew a whole lot more than others ( thanks for posting )... but often these big consumers offer better baseline performance...

With these cases... do as you did, and;

  • compare with a power meter
  • eliminate/swap the power supply
  • try the steps above and try to minimise / identify the hogs

In 30%+ of cases it will be power supply... most of the rest old/inefficient design ( not much you can do about that )... and a handful chew more for a reason... but you would see / be able to tell the performance difference fairly easily...

Diluted to the base questions;

  • Is this design / power supply inefficient / efficient?
  • Does this devices efficiencies come at a performance hit?

As a travel router i'd love a MT300A or an all in one SoC... but for my home, the more dedicated chips ( more power ) within the router the better IMHO... a little more pricey... alot more robust...

In general, the higher end your router is, the more power it will require - be it for providing power to USB devices, or to drive 802.11ac or 802.11ax wireless (especially at full performance). Top end routers can easily chug ~20 watts idle.

Acknowledged. But the difference between the rpi4b and the wrt1900acs is remarkable. The rpi4b is a quad core scaling between 600 and 1500MHz, the wrt1900acs a duo core with a fixed frequency of 1600 MHz.

The power consumption of a wrt1900acs pays in 2 years the price of a NanoPi R1, which I ordered today.

The costs of electric power will definitely increase in the future. Therefore I pay more attention to the power consumption of my routers. They are running 24/7 for VoIP and mostly idling.

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You're comparing apples with oranges here. A single connected (doesn't even need to actively transmit data) 1 GBit/s ethernet port (100 MBit/s needs less) requires between 1.0 and 1.2 watts, your WRT1900AC has five of those, the RPi4 a single one (and by using a switch, you're merely externalizing the power consumption). While wireless needs less power than ethernet beyond 1 GBit/s, it's also a considerable part of the calculation.


Adding a related thought: power consumption=heat. I am less concerned with electricity cost, and more concerned with whether I can fry an egg on the router.

My home has a small enclosed metal telecom junction box for the home ethernet lines with an electrical outlet built into it. The box is recessed into a closet wall. I sleep better at night knowing the EdgeRouter X enclosed in this box generates very little waste heat.

Modems are another matter. I find they are either based on yesterday's technology and run hot, or they are part of a giant "ISP Gateway" device that is too big for my enclosure.

The 9.5 W of the wrt1900acs result from 2 gigabit interfaces connected (1 wan, 1 lan). The one gigabit interface of the rpi4b combines 4 vlans connected via an 8-port switch (1.5 W). The single rpi4b interface had more traffic than the 2 interfaces of the wrt1900acs.

If you compare the archer C7 and the wrt1900acs: both have 5 gigabit interfaces, but the archer uses only 3.5 W (with all interfaces connected to active devices).

If your numbers are correct, why does the archer not use more than 3.5 W with all interfaces connected to active devices?

In general, you can check powertop (there is a package for it) and try on your own risk powersaving settings.

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wrt1900acs has a 1.6GHZ ARM dual core CPU compared to a 750MHz MIPS single core CPU. The former generates more heat and uses more power. The latter does not. It also has no heatsinks.

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I have powertop on my linux laptop. Didn't know, that there is a package for openwrt. I'll give it a try.

Thanks for your hint.

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I know, but the difference in power consumption is enormous.

It's a more powerful router.

Why to not buy the Nanopi R2S it's nearly the same price.
No wifi, but dual gigabit (941 Mbps both in/out).
FriendlyWrt with docker.
Annd following this 2 video full load it consume betwen 2.6 & 3w.
it will cost you in the worst case (full load 24H/7) 7,9 euro year

Is it such more powerful than it uses more electric power?

I think the Archer C7 handles electric power more efficiently than the WRT1900ACS.

Nexx WT3020. Though I cant mesure it power consumption at a time

Yes it is.

Up to now I didn't find any company, that sells it in Germany.

The German distributor of FriendlyARM products just delivers the NanoPi R1, not the R2S. But that may change from one day to the other. Hopefully!

But in the specs I see it's using an usb3 ethernet adapter, you can find the rock64 bought mine at

~25$ + an gigabit adapter if you think it satisfies you

You can order from AliExpress.
But keep in mind it's not supported by openwrt.
It's a fork of openwrt from friendlyarm

I know, it's not listed in the table of hardware. But there are images for the H5 chip, that should work for wired networking. I don't need wireless in the router.