Paper Title
Accumulation System of Pressed Air using the Cold Energy

Abstract
In our study, we develop a new method how to use cold energy in a cold area. Namely, an energy conversion system which extracts cold energy from the cold air outside is developed. In the system, a basic principle that the volume of water shows ten percent increase when it is frozen. If the air and water are enclosed in an airtight container at the same time, the air is pressed by the frozen water when the water starts to freeze. The pressed air can be stored into an accumulator. Even in a winter season in a cold area, the air temperature outside can across the freezing point in a day. This means that the phase change both from water to ice and from ice to water can repeat in each day. Then, the pressure from the pressed air can be increased in an accumulator due to the repeated phase change. However, the total amount of the pressed air is very small. Keyword - Cold Energy, Accumulator, Pressed Air, Energy Storage