Abstract :
The kinetic energy storage has stepped from an initial development status to an operational phase on prototypes. The first energy wheel has been implemented as an uninterruptible power supply unit for a rural telephone exchange, close to Paris. This paper draws the 1st conclusions after one year of operational experience. At first thle operatirng principles and performance of the model are recalled a high speed rotor, magnietically suspended, inside a vacuum container, activated by a brushless motor. Being reversible, this motor arts as an electrical energy generator in case of failure or microcuts from the mains. The confirmation of several expected advantages is well underway: no failure, no maintenance, no detrimental effect of cold winter environment, constantly well down level of available back up energy. Necessary improvements are also identified, such as mass reduction, easy implementation, vacuum tightness, AC supply.
