Raspberry Pi power consumption?


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I've been thinking about getting a Raspberry Pi to become a downloader/smart TV solution, given it's low price and low power consumption. Can anyone tell me how much power it will actually consume if plugged in and downloading via Ethernet? I don't understand all the power statistics that I've found on the Internet as they confuse me.

Can anyone tell me what the costs could be, or what the power consumption is compared to other electrical devices, such as a light bulb, router, homeplugs, etc?

Also, what's the normal power consumption for homeplugs and a normal router?

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The official figures for the ORIGINAL 256MB model B one is 5 watts, it runs on 5v at about 1 amp, 5*1 = 5w.

The new 512MB one that allows a lot more power to passthru to the USB slots (model B) will probably use more depending on what's plugged in.

Original Model A from what I remember is 5v at 0.5a meaning 2.5w, not a clue about the new model A but it doesn't have ethernet anyway.

 

In theory the original RPi B uses half the power an 11w energy efficient light bulb uses, well that's the raspberry pi itself, the actual power depending upon the power supply you use, seeing as most plug-in USB power adapters are upto about 75% efficient.

 

Routers probably use a bit more power due to the multiple ethernet isolation transformers inside them, again it all depends upon the router, the manufacturer and other things.

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For 'SmartTV' functionality, I think you might be better off with a with an Android MiniPC like this one.  They use the same amount of power but is far more capable than the RaspPi (I have both btw).  I found out like most do about the RaspPi is that you run out of headroom fast when it comes to performance.

 

Also, the MK 809II is only a few pounds more expensive as well.

 

I've linked mine to my Google account where I have access to stuff like Plex which can stream movies and TV series straight off my server and it can handle 1080p content fine. :)

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That's great. I only planned on using it over night, or an hour or two on an evening, so it should be even less. Thanks for the replies. :)

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Remember that it's absolutely fine for streaming over ethernet, but very slow as a download box. IO over USB gets very slow very fast and the ethernet doesn't go that fast either.

 

I have mine as a tiny Tomcat web server now, runs remarkably well. Plan is to put XBMC on it (OpenELEC) when I get a new TV.

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Remember that it's absolutely fine for streaming over ethernet, but very slow as a download box. IO over USB gets very slow very fast and the ethernet doesn't go that fast either.

 

I have mine as a tiny Tomcat web server now, runs remarkably well. Plan is to put XBMC on it (OpenELEC) when I get a new TV.

What does it equate to as a download box though? My broadband can only download at 1MB/s. I assume it'll be good enough for that?

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I use a 5V 1.5A power supply (thats a max output of 7.5W) and it powers my raspberry pi with ethernet cable, as well as  750mA 2.5" HDD its using to improve throughput.

I can download/upload to the Pi around 20MB/s this way, opposed to around 4-5MB/s off SD, plus I have a TB of storage.

 

Highly suggest anyone who wants real throughput from the Pi follow this guide: http://zeroset.wordpress.com/2012/10/03/move-an-existing-raspbian-installation-from-memory-sd-card-to-usb-flash-drive-stick

 

My XBMC box runs from a 5V 1A supply without any problems, and if you use HDMI-CEC and have no need for a wifi adapter you can likely get away with a 5V 0.5A or 0.75A supply. Ensure you are using a stable quality supply and a good microUSB power cable. 90% of raspberry pi issues come from these 2 things.

 

Most routers use 24W (12V 2A) you can determine this by unplugging the AC adapter and reading it. You should see something labeled OUTPUT: 12V --- 05.A (should be a solid bar with dashes under it) this states it can supply 12Volts at 0.5Amps.

 

Power is Voltage multiplied by Amps, so just multiply them together and thats the MAX amount of power it can use under full load. In the case above, 12*0.5, it'd be 6W of power. Most devices operate at most in the 60-80% of their supplies rating, to prevent failure with power brownouts or spikes. For maths easy we assume it uses the MAX power all the time.

 

You can do a lot of stuff on them too. like running XBMC while downloading torrents and having an SSH VPN tunnel is just the tip of the iceberg.

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What does it equate to as a download box though? My broadband can only download at 1MB/s. I assume it'll be good enough for that?

It'll do fine for that. My connection is 15MB/s and it starts to struggle at that point (very high CPU, especially with torrents).

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