NOVELTY - Growing crystalline anatase nanowires upon a substrate involves deposition of titania onto a substrate; conversion of the titania into titanate nanowires; and treatment of the titanate nanowires to produce crystalline anatase nanowires. At least one reactor is used in at least one step, simultaneously and/or sequentially, and in a continuous and/or batch manner. The reactors are heated for duration of 0.25-48 hours. The reactors are hydrothermal reactors or microwave-driven hydrothermal reactors. In the method, at least one solvent is used either simultaneously or sequentially.    USE - For growing crystalline anatase nanowires upon substrate to produce electricity; in a device for the production of electricity from radiation; for catalyzing and/or promoting chemical reactions; in the catalysis and/or promotion of chemical reactions with radiation; in an energy storage device (claimed); in photovoltaic device; and in solar cells such as liquid-based dye sensitized Gratzel solar cells (DSSCs), heterojunction solar cells, Forster resonance energy transfer (FRET) based solar cells, and organic solar cells.    ADVANTAGE - The method provides improved self-assembling, vertically-oriented 1-D nanostructure comprising crystalline structural elements that are synthesized upon a transparent conductive substrate for use in photovoltaic and other applications. The high surface area crystalline anatase nanowire films offer enhanced light absorption without a corresponding penalty in unwanted charge recombination, and as such offer great utility in a variety of 3rd generation photovoltaic designs, including dye sensitized, quantum dot, and multiple exciton solar cells. The method allows production of 1-D anatase nanowire films in a cost effective manner, and without damage to the underlying transparent conductive layer to minimize series resistance. The films are fully crystalline for superior charge transport, and are of extended length for enhanced light absorption.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a device comprising at least in part of the crystalline anatase nanowire array for use in the production of electricity from radiation; and    (2) a device for energy storage in which at least one electrode comprises at least in part of the crystalline anatase nanowire array.