Learning from the concepts used by green plants photosynthesis, we have developed nanostructured systems affording efficient solar light harvesting and conversion to electricity and fuel [1].Solar cells using dyes or semiconducting nano-particles as light harvesters supported by mesoscopic oxide films have emerged as credible contenders to conventional p-n junction photovoltaic devices.Separating light absorption from charge carrier transport, dye sensitized mesoscopic solar cells (DSCs) were the first to use a three-dimensional nanocrystalline junction for solar electricity production.A molecularly engineered donor-acceptor porphyrine dye when used in conjunction with a Co(Ⅱ/Ⅲ) complex based redox electrolyte has reached a power conversion efficiency (PCE) of over 12 percent [2] under standard air mass 1.5 (AM1.5) reporting conditions (25℃, 1000 Watt/m2 solar intensity).The PCE of the same system attains 26% under ambient and indoor light conditions.