The invention encompasses a method for production of electric power from a system of contacts of nanostructured conductive surfaces with a thin water-containing layer, and a hydroelectric generator for carrying out the method. The basis of the invention is a discovery, confirmed by experiments, that the contacts of the conductive surfaces, having nano-dimensional structural and/or parametrical heterogeneities, with the water-containing layer, having a thickness from several nanometers to a fraction of a millimeter, under certain conditions, described in the present disclosure, generate electromotive force in an external electrical load. The invention utilizes new principles for building power systems, which can find further wide application in various areas of science and technology.