Concentrated photovoltaics (CPV) is a photovoltaic technology that generates electricity from sunlight. Contrary to conventional photovoltaic systems, it uses lenses and curved mirrors to focus sunlight onto small, but highly efficient, multi-junction (MJ) solar cells. Despite the need for additional concentrating optics, and the usage of more expensive MJ-cells, CPV systems, and especially High concentrating photovoltaic (HCPV) systems, have the potential to become competitive in the near future. They possess the highest efficiency of all existing PV technologies. And a smaller photovoltaic array also reduces the balance of system costs.