To provide an electric field forming panel used for a prefab capable of preparing a prefabricated environment so as to cause supercooling and a prefab equipped with the electric field forming panel.SOLUTION: The electric field forming panel 1 used for prefabrication has flexibility and includes a mesh-like flat electrode 3, a first panel material 7 covering one side of the flat electrode 3, and a second panel material covering the other side of the planar electrode A panel body 2 having a second panel member 9, and an insulating material 5 disposed between the first panel member 7 and the flat electrode 3. When a voltage of 1 kV to 5 kV is applied to the flat electrode 3 in a sinusoidal waveform with a frequency of 48 Hz to 62 Hz to the flat electrode 3, the electric field is formed within 3 m from the surface of the flat electrode 3 on which the insulating material 5 is not disposed. An electric field space having an electric field strength of 3 kV / m to 15 kV / m is formed and the environment of the electric field space is adjusted to a state where supercooling in which the water is in a non-frozen state occurs at a temperature below the freezing point.(FIG.【課題】プレハブ環境を過冷却が生じるように整えることが可能なプレハブに使用する電場形成パネル及びこの電場形成パネルを取り付けたプレハブを提供する。【解決手段】プレハブに使用する電場形成パネル１は、柔軟性を有し、メッシュ状の平面電極３と、平面電極３の一方側を覆う第一パネル材７、及び平面電極の他方側を覆う第二パネル材９を有するパネル本体２と、第一パネル材７と平面電極３との間に配置される絶縁材５を備える。電場形成パネルは、平面電極３に周波数４８Ｈｚから６２Ｈｚの正弦波形で１ｋＶから５ｋＶの電圧が印加されることで、平面電極３の絶縁材５が配置されていない側の表面から３ｍ以内に０．３ｋＶ／ｍから１５ｋＶ／ｍの電界強度を有する電場空間を形成し、電場空間の環境を氷結点以下の温度で水が非凍結状態となる過冷却が起こる状態に整える。【選択図】図２
