Electrical energy storage systems for energy networks

Dispersed electrical energy storage systems are expected to work for load leveling, fluctuation smoothing, uninterruptible power supply and emergency power source. Their introduction seems to be essential in order to control the future complicated energy utility networks. In this paper, the characteristics of promising energy storage systems by pumped hydro, compressed air, secondary batteries, superconducting magnet, flywheel or capacitors have been surveyed and discussed. From the results, their characteristics and suitable application fields have been clarified.