YoMo
You Only Meter Once - The open hardware smart metering system
...The metering system consists of a coordination unit, a raspberry pi, and several smart meters, arduino boards equipped with communication shields and our self-designed yomo metering shield.
The smart meters are attached to household devices and monitor their energy consumption. The gathered data is timestamped and transmitted to the coordination device. This device offers interfaces to control the smart meters. On top of the software runs a apache webserver that provides all estimated data on our yomo project homepage.
The system does not need any maintenance and works out of the box after the devices were integrated into the households Wi-Fi network.
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