Arduino home energy consumption monitor project

Dear all,

I've been working recently on a little project, and I'm considering to publish it on the playground. Before doing so I'd like a bit of advice, though.

First a little bit about the project. Since we are consuming too much electricity (8000 kwh/y) I'd like to monitor and record the power consumption in our house. This is compexified by a solar power plant which we installed mid last year. So we have two electrical meters: One that measures the production of the solar panels, the other one is a two-way meter that measures how much energy we are delivering to or retrieving from the public energy grid. It should be noted that from the solar production we only deliver the excessive electricity into the grid after our house is served.

The meters are so-called eHz-meters. They follow the IEC 62056-21 standard, which means that they come both with an infrared output port which emit serial datagrams every so many seconds at 9600 baud, 7 bit, even parity. A datagram might look as following:


In addition, they also have a visibly blinking LED which triggers every 1/10 Wh.

The solar panels are monitored and recorded by a device called Solarlog 500. This device has an S0 input port for the own power consumption monitoring and recording.

What my Arduino now does is that it receives the information from the two infrared ports and the blinking LED, adds the solar production to the energy retrieved from the grid thus computing the current consumption in the house, and then generates the necessary S0 impulses towards the Solarlog. The project also involves a few phototransistors and an optocoupler, currently on a breadboard.

How do I best go about to describe the project on the playground? For instance, which tool is used to generate these nice Arduino schematic drawings? Also, it seems that I can't currently create an account on the playground -- the registration page is empty?

Kind regards, Sebastian

Ok, I don't usually like it when people answer their own questions, but I think I found my way and will describe my project on

Kind regards, Sebastian

HI Sebastian,

Can you explain what the codes mean?

Maybe you have a postable sketch that parses this info to something that means something to humans :)

Thanks, Rob

Hi Rob,
1-0:1.8.1*255(004954.5561) means we’ve taken 4954.5561 kWh from the power network so far.
1-0:2.8.1*255(002111.2756) means we’ve distributed 2111.2756 kWh into the power network from the solar panels.
1-0:96.5.5*255(82) is status code 82.

All of this is described in more detail in, e.g.,

Kind regards,

Why did you remove the english posting on the wiki? There's only the link to your german website now. Not everybody on this planet speaks german, so could you please put the english version back on the wiki?