Thursday, January 31, 2013

Raspberry Pi power consumption - One month after

Here is the end of January  As promised, I'll do a checkpoint about my Raspberry pi power consumption.

My consometer measured a total power consumption of 1,8 kWh, this is absolutely very low.

I'll do another measure in two month for confirmation.

Crédit photo: M. G. Loppé [Public domain], via Wikimedia Commons

Sunday, January 20, 2013

A bug on the teapot - Firefox Debugging tools

I received an email from a visitor telling me there is a bug on the site of my teapot.
In summary, he told me that the debugger says him that my teapot it returns him a code 200 instead of a 418 code.

But how to check the presence of this bug by myself? I explored the development tools in the Firefox menu to find the option "Web Developer / Web Console".

This tool displays some technical informations about the current page in a banner that appears at the bottom (remember to refresh the page if nothing is displayed)

Indeed, the return code 200 is the code sent after a HTTP request accepted by the server. My teapot hosting a web server, it returns this return code when you visit my page.

It is also noticed traces of my usage of Google Analytics with this tool.

Now that I'm aware of this failure, I'll try to find a way to return a true 418 code in a future post.

Sunday, January 6, 2013

Raspberry Pi power consumption - One week after

Here is a first checkpoint about the power consumption of my Raspberry Pi.
Today, after one week of measuring my powermeter announces a total consumption of 0.4 kWh.
Given the low power consumption and the poor accuracy of the tool, I'll do the next measure at the end of the month.

Credit photo: Thomas Bresson (originally posted to Flickr as Eclair) [CC-BY-2.0 (], via Wikimedia Commons

Tuesday, January 1, 2013

Raspberry Pi power consumption

To start the new year, I decided to look at the power consumption of the project.

I found a power meter in my stuffs, which is probably not very accurate, but should allow me to give an idea of what consumes and costs my Raspberry Pi. I want to take into account the conversion from 240 Volts to 5 Volts.
My power meter is the MPM 50 model of brand IDK.

Due to the low consumption of Rasperry Pi, it is possible that the power meter consumption is significant. According to the manual it consumes less than 2 watts.

The experiment just started, so I have didn't accumulated cumulative consumption yet, but here are the first informations on the instantaneous data given by the device:
237 Volts
0,02 Ampères
2,5 Watts

For your information, the regulated tariff for electricity from EDF (Electricité de France) is € 0.0812 per kWh excluding taxes and € 0.1249 per kWh including taxes.

I'll try to give regular updates on measured consumption.