Raspberry Pi and Energy Harvesting Wireless Devices

Do-It-Yourself home automation enthusiasts will welcome the idea of a wireless arrangement when setting up devices for automating their homes. It would be still better if these sensors and switches did not require an external power source to make them work. EnOcean Pi makes both these scenarios possible, with the tiny ubiquitous single board computer, the Raspberry Pi or RBPi, acting as a home automation server.

Therefore, with the EnOcean Pi, enthusiasts can set up home automation systems without any cables connecting the self-powered sensors and switches. Depending on information from sensors measuring temperature, humidity and from those detecting human presence, the RBPi may switch lights on/off and control blinds on windows.

Enthusiasts may either have sensors and actuators communicating directly with one another, or control them through an intelligent and smart home server. The latter allows adding remote sensing and remote control for home automation, which can be done conveniently through a PC or a smart phone. This type of home server is ideally suited for a tiny single board computer such as the RBPi. The EnOcean Pi then acts as a gateway controller to the EnOcean radio world. Element14 offers three types of kits for this purpose – the starter kit ESK 300, the developer kit EDK 350 and the Sensor kit PSK 300.

The wireless module, EnOcean Pi, comes in three versions – 868MHz for Europe; 315MHz for Japan, India and North America; and 902MHz for North America. This wireless module connects to other self-powered EnOcean sensor modules, which generate their own power through energy converters that use temperature differences, light or mechanical motion as an energy source. Therefore, the RBPi receives necessary data for intelligent control from maintenance-free sensors and actuator solutions.

It is always possible for OEMs and developers to design low-cost gateways for embedded applications including smart home solutions. Rather than developing new products from scratch, developers now have the option of using the EnOcean Pi and RBPi for creating a ready-made smart home box. This can process and visualize the data coming from self-powered wireless sensors, thereafter providing central control of a wirelessly connected house.

Users wanting to develop and integrate quick applications can download the EnOcean Link Trial Version middleware that comes with the new Pi accessory. The RBPi acts as a gateway, automatically controlling the EnOcean-based energy harvesting wireless sensors, switches and thermostats. That ensures a comfortable management of lighting, shading and HVAC, thus helping to save energy.

For a bi-directional communication via radio and serial interfaces, EnOcean Pi also offers the EnOcean Smart Ack controller functionality. The RBPi can use the serial interface to send and receive radio messages transparently in both directions. In this case, using the Smart Ack technology, the EnOcean Pi acts as a postmaster and controls up to 20 bi-directional sensors.

The EnOcean Sensor Kit has a set of three wireless sensors that includes a temperature sensor, a reed switch and a push button. Rather than use a battery, the sensors have a solar cell that supplies them with power. Each sensor has a wireless module with a built-in antenna requiring no cables. That makes the sensors totally self-powered and maintenance-free.