A solar power system includes at least one alternating-current module and a communication apparatus. Each alternating-current module includes a solar panel and an alternating-current inverter. The communication apparatus connects to the alternating-current module and controls stand-alone power-generating operations on the alternating-current module. The communication includes a module connector and a control circuit. The module connector is configured for connecting with the alternating-current module. The alternating-current module can be parallel-connected on a household power grid selectively. The communication apparatus can transmit a stand-alone power-generating command to the alternating-current module. The alternating-current inverter may cancel an anti-islanding protection procedure thereon according to the stand-alone power-generating command.