Photovoltaic energy (PV) is one of the most important renewable energy sources in terms of global installed capacity. Although the majority of all new PV systems are based on crystalline silicon technology, novel technologies are being explored based on nanomaterials and organic cells which could give rise to breakthroughs in terms of efficiency. There is a wide range of options to convert sun into electricity such as Fresnel modules that use optical elements to increase the amount of sunlight onto a PV cell. Concentrating PV modules/arrays track the sun and use concentrating devices to reflect direct sunlight onto the solar cell to produce electricity directly. The main challenges for PV technology are to further improve solar cell efficiency while lowering production costs. Advances in efficiency, reliability and reproducibility require a better understanding of material properties and fabrication processes. Photovoltaic applications can be combined with practically any electrically powered load and controlled efficiently in a smart grid. They can be found in an industrial context, in new building construction and refurbishment projects.