An operation planning method performed in a system including a power generation device, a first electric load operating using power generated by the power generation device, and a second electric load which generates heat using power generated by the power generation device. The support unit includes a support frame and a locking element. In a particular embodiment, the movable mirror assembly includes an inner strip spaced apart from the fixed layer by a first distance and an outer strip disposed approximately adjacent to the inner strip and spaced apart from the fixed layer by a second distance which is greater than the first distance.