A device for generating utilizable energy from potential energy of motor vehicles of street traffic is already known from U.S. Pat. No. 4,339,920. According to this patent a plurality of flexible containers, which are filled with an incompressible fluid are squeezed together, and subsequently the fluid is directed, possibly after passing a flexible and hence extendable container, to a hydraulic motor for generating utilizable energy. The containers, being compressible by the gravity of a motor vehicle, are disposed in small chambers which are inserted within the traffic lane, whereby the covers for these chambers can be urged by the gravity of a motor vehicle into a position underneath the surface of the traffic lane. Thereby the tire of the motor vehicle is hit very hard like in case of driving through potholes.
Furthermore, a device for generating utilizable energy from potential energy of motor vehicles is known from German Patent No. DE-OS 35 42 031. According to this patent flexible containers are filled with water by means of pivoted rigid plates and the urged out water is fed for generating energy into a turbine.
A disadvantage of the device shown in German Patent No. DE-OS 35 42 031 is that there has to be taken special measures for driving back the urged out water into the flexible containers and thereby to move back the pivoted plates into their original position. Furthermore, the requirement of having to urge incompressible fluid out of the flexible containers has shown to be disadvantageous because, in this case, the energy cannot be accumulated without taking additional measures in the form of a fluid under pressure and hence a turbine cannot be driven in an optional moment.