The spectrum is the chosen design option which is inspired by Spectrum from Sun ray. With goal to design a headquarter of the solar power factory in Ninh Thuan, round shape is used as symbol of a power center, which called “ Trung Nam ‘s Sun”, where produce and operate resource of light and energy, just right as its name “ Solar headquarter”. Spectrum is a light sequence with different frequencies, when projected on a plane creating a colorful color range. The “spectrum façade” of the building is made of aluminium lourvers, providing motion effect when light shines on the façade from outside, and creates a shadow effect as the light enters the interior. AND designed architecture details and interior with criteria that maximize sustainable beauty by using the beauty of light on the surface of the material.