Nissan engineers use the Xenon Weather-Ometer (XWO) to test material durability in different climate conditions. To evaluate the effects of solar energy on paint and other materials, a 4,000-watt Xenon bulb bakes nearly 100 samples at the same wavelengths as the sun. Samples rotate around the Xenon bulb to imitate earth’s orbit – and because the “sun can shine” 24 hours a day, it takes half the time to test paint samples.