ScatterWeb, a distributed, heterogeneous platform for the ad-hoc deployment of sensor networks offers hardware together with open, fully documented software for the deployment of embedded sensor networks. Already low power by design, the sensor nodes offer additional energy conservation mechanisms and support energy efficient routing, such as, e.g., solar-aware routing. In order to enable a battery-free operation, the nodes implement permanent power sensing and start the transmission if and only if the energy stored in a capacitor is sufficient for the complete transmission plus the reception of an acknowledgement. Energy-aware routing takes the current incoming power of environmental energy sources into account. Depending on the current power generated by, e.g., solar cells, traffic is always forwarded by the nodes having sufficient power. Together with additional power saving, auto-configuration, and remote reprogramming techniques, these mechanisms enable ScatterWeb nodes to survive many years in real-life scenarios without any on-site maintenance.