This RaspberryPi project uses weather data to estimate the share of renewable energy in the power grid. From this, the value of CO2 emissions per kWh can be calculated. Visit https://www.agora-energiewende.de/service/agorameter/ for an overview of the electricity mix and the emission value.

The estimated emission value is displayed similar to a traffic light on a green-red scale by leds connected to the RaspberryPi.