Fleischmann and Pons effect (FPE) is the production of excess power during electrochemical loading of deuterium in palladium. This effect has the following features: (1) It is a threshold effect (loading D/Pd > 0.9). (2) It is unobserved when electrochemical loading is performed with hydrogen from light water. (3) It is unexplainable as a chemical effect. (4) It occurs only if the involved materials.