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EBS - Energy Harvester

The Institute of Telematics currently experiments with a variety of different devices converting ambient energy into electrical energy. The charateristics of these devices - ranging from a thermal harvester to solar cells - are explained in the following. This reserach is done in the context of the project EBS.

Solar Cell

Solar cells are probably the best known and most widely used method to harvest electrical energy from the environment. They convert incoming light into electricity, the efficiency depends strongly on the intensity and spectrum of light. Solar cells can be produced in different shapes and therefor can be easily integrated into their surroundings. Due to the long experience and dissemination solar cells are now also fairly inexpensive. In full sun the construction we use generates an output of up to 100 mW, while in the shade (buildings, clouds) the power is reduced to about 15 mW.

Water Turbine

At many places where clean water flows, this small turbine (Kinetron WTG120) can help to generate electrical energy. For example it can be integrated in the cold water pipe of a sink, where it acts additionally as a resource-saving flow limiter. Their optimum efficiency has this turbine at a flow rate of 2.5 l/min, in which it delivers a power of 227 mW, the minimum flow rate is 2 l/min.

Vibration Harvester

The prototype PowerQb of HSG-IMIT ( converts vibrations into electrical energy, depending on the type most effitiant at frequencies of e. g. 64.5 Hz or 109.1 Hz. Thus they can be used in many places in which an environment is in mechanical vibration, for example in a motor vehicle with a combustion engine, within a speaker or a refrigerator cooled by a compressor. The achievable power varies depending on the type, between about 1.6 mW and 5.4 mW.

Thermal Harvester

Seebeck elements produce electrical energy, if they are inbetween two media of different temperature. E. g. it is possible to embed them in dishes, in which hot beverages are served.

Door Harvester

A chain of magnets with alternating polarity, integrated into the floor below a door can stimulate a perfectly matched combination of coil and core metal mounted at the door in a way that alternating current flows through the coil current, whenever the door is opened or closed. With professional embedding in the floor and the door you feel no mechanical resistance due to the installation and no aesthetic impact.