NOVELTY - A porous electrode comprises a porous film (A) (232), with through pores and an electrically conducting material comprising conductor and semiconductor, having an average pore size (d1) of 0.02-3 microns and a porosity of 40-90%. The electrically conducting material (231) is filled in the through pores of the porous film (A).    USE - For a composite element of dye-sensitized solar cell and an electric double layer capacitor (claimed).    ADVANTAGE - The inventive porous electrode exert a high efficiency of light usage and is highly flexible.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (a) a composite element comprising a porous electrode (23) and a porous film (B) with through pores disposed on one surface of the porous electrode, where the porous electrode comprises a porous film (A) as above, and the porous film (B) having an average pore size smaller than the average pore size (d1) of the porous film (A);    (b) a dye-sensitized solar cell, comprising a first and second substrates (21, 26) opposing each other, a counter electrode, a porous electrode and a collecting electrode that are arranged between the first and second substrates in this order as viewed from the first substrate, and an electrolyte interposed between the counter electrode and the collecting electrode through the porous electrode; where the porous electrode is an electrode comprising a porous film (A) as above, the second electrode being a transparent electrode, the semiconductor being isolated from the counter electrode, and the semiconductor carrying a sensitizing dye (27) on the surface;    (c) an electric double layer capacitor, comprising a first and second substrates opposing each other, a counter electrode, a porous electrode and a collecting electrode which are arranged between the first and second substrates in this order as viewed from the first substrate, and an electrolyte interposed between the counter electrode and the collecting electrode through the porous electrode, where the porous electrode is an electrode comprising a porous film (A) as above, and the conductor is isolated from the counter electrode;    (d) a method for producing a porous electrode, comprising applying a liquid containing an electrically conducting material comprising conductor or semiconductor to one surface of a porous film (A) as above; and    (e) a method for producing a composite element, comprising applying a polymer solution comprising a polymer and a solvent to one surface of a porous electrode to form a layer of the polymer solution, the porous electrode comprising a porous film (A) as above; and removing the solvent from the polymer solution to form a porous film (B) as above.    DESCRIPTION OF DRAWING(S) - The figure is a schematic cross-sectional view of a dye-sensitized solar cell.    First and second substrates (21, 26)    Porous electrode (23)    Sensitizing dye (27)    Electrically conducting material (231)    Porous film A (232)