The branch of technology associated with the production of electric current at the junction of two substances is referred to as photovoltaics. Photovoltaics have started substituting fossil fuels as a major form of energy generation. They target higher efficiencies and/or lower costs to bring PV at par with grid electricity. Third generation PV technologies may surmount the basic limitations of photon to electron conversion in single-junction tools and, hence, enhance their efficiency and cost. This book introduces prominent advances in these techniques, namely nanostructures and dye-sensitized cells. Some of the significant issues that the book discusses are life cycle assessment of OPV, multiscale modeling of heterojunctions, new materials and architectures for solar dye-sensitized cells, field performance factors and polymeric films for lowering the cost of PV, among others. Various renowned professionals have contributed to the book, compiling knowledge necessary for advancing this new generation of PV.