A horticulture facility includes a first set of LED luminaires disposed in a grow room of the horticulture facility, a second set of LED luminaires disposed in another grow room of the horticulture facility, a centralized power supply and power transfer switches. The power supply includes DC/DC power converters each having an output. The power transfer switches include a first power transfer switch coupled to the output of one respective DC/DC power converter of the DC/DC power converters. The first power transfer switch is configured to switch between a first position for coupling the output of the respective DC/DC power converter to the first set of LED luminaires, and a second position for coupling the output of the respective DC/DC power converter to the second set of LED luminaires. Other example horticulture facilities and electric power systems are also disclosed.