Since the spectral structure of carbon arc lights is compatible withAM0, they are used as a light source in space solar simulators andmulti-junction solar cell optimization rather than for terrestrial photovoltaic panel tests [55,56]. Accordingly, they are slightly compatible with the natural sunlight spectrum and their wavelength is weaker than that of xenon lamps except between 320 nm and 339 nm [57,58]. Other disadvantages of carbon arc lights can be stated as short operation time, instability during operation and extreme blue radiation that propagates carbon arc [17]. Since they are commonly used in space solar simulations, it can be seen that carbon arc lamps were also used in the first space simulation applications of NASA [59–61]. Fussell stated that the technical report showed that the carbon arc lamp could be a good solar simulator [62]. The report by Ross and Bickler states that carbon arc lamps are a good choice for solar simulations but solutions should be found for the instability problem [63]. Mirtich used a carbon arc lamp in the solar simulator he used for the test he performed. He emphasized that the spectrum of the lamp was completely matched to the Johnston curve [64], but the performance of the simulator changed from time to time [65]. High pressure sodium (HPS) vapor lamps developed by Louden andSchmidt in 1965 [66,67] are used as light sources in solar simulatordesigns and applications due to their high efficiency, long life cycle and wise spectral range (250–2500 nm) [31,68–71]. According to Grish [72] the spectral irradiance of sodium vapor lamps mainly lies around the yellow region of the visible spectrum. This yellow region is called DLine and corresponds to a wavelength of about 586 nm [66,73]. Although HPS vapor lamps are widely used in practice, the lamps are comparatively expensive and require auxiliary electronic devices to regulate lamp power [74]. Besides carbon arc lamps, argon arc lamps were also used in the first solar simulation studies. In 1972 Decker stated that argon arc lamps were a suitable light source for simulations with high uniformity, stability of irradiance, clean operating characteristics for a 400 kW argon arc lamp used for solar simulations. However, the simplification of maintenance also emphasized that lifetime and reliability should be increased [75]. Argon arc lamps have a 6500 K color heat emission spectrum with a 275–1525 spectral interval [76]. In the 75 kW High- Flux Solar Simulator study by Hirsch et al. [77] in Zürich in 2003, a high pressured (7 atm) closed argon arc lamp was used as the light source. In general, arc lamps provide additional power in visible,infrared and ultraviolet wavelengths and have outputs similar to realsolar radiation with optic fibers developed in AM 0 and AM 1.5standards [78].