PURPOSE: To produce a large volume of gaseous methane continuously in pumping-up power stations by providing gas feed pipes for the purpose of equalizing and controlling pressures of an upper basin and a lower basin other than water channels for falling-down power generation in said power plants.

CONSTITUTION: A pumping-up power station consisting of the closed system wherein the gigantic basins which have sealing covers consisting of dark color plastic sheets for transmission and absorption of solar heat reinforced with metallic plates or metallic framework for collection of solar heat and of which the circumferences are provided with heat insulation linings are provided as an upper basin and a lower basin irrespectively from existing river water sytems is provided. Gas feed pipes for equalizing and controlling the pressure of both basins are provided other than water channels for falling-down power generation connecting both basins to collect gaseous metahne. The gases in the gas feed pipes are transported reverse to the upper basin→ the lower basin if sewage is in the water channels is in the lower basin→ the upper basin and to the lower basin→ the upper basin if the sewage is in the upper basin→ the lower basin.