3 title: Saving power of powerful printers
4 date: 2018-07-01T17:14:46+00:00
7 guid: http://wp.realraum.at/?p=1032
8 permalink: /2018/07/saving-power-of-powerful-printers/
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32 At home, my Samsung laser-printer uses 15W during standby. So, a few years back, in order to save power, I put it on a USB-controlled power-plug. Pretty soon I added a tiny script that would query cups if a print-job was queued and would switch the printer on and afterwards off again. It turned out to be a pretty effective power saving measure.
34 <p style="height:150px;">
35 <img src="http://wp.realraum.at/wp-content/uploads/2018/07/usbpowerswitching-300x148.jpg" alt="usbpowerswitching" width="300" height="148" class="alignleft size-medium wp-image-1035" />
38 Our two very big and reliable printers at realraum were even more power hungry, so I wanted to to something similar for the space.
40 Using the hardware I had on hand, I cobbled together the following:
42 * A BeagleBone Green to act as cups print-server and to run the python scripts.
44 * An empty 230V power-plug case, housing a 5V power-supply (for the BB) and a small opto-coupler isolated relay to switch the plug.
46 * A second power-plug case with a second small opto-coupler isolated relay.
48 While there is a lot of room for optimization, like a leaner BeagleBone image and better housing for the power-plugs, printing- and power-saving-wise it works very well.
50 As always you can find our <a href="https://github.com/realraum/printerbone" title="Code on Github" target="_blank">code on Github.</a> Stay tuned for updates.