According to one embodiment, a power control apparatus includes a receiving unit, an environment-data acquiring unit, and a calculation unit. The receiving unit receives, from a power supplying side, a power-consumption reduction request for reducing power consumption at a power demanding side. The environmental data acquiring unit acquires, from the power demanding side, environmental data representing environmental state of the power demanding side. The calculating unit calculates a power-reduction value based on the environmental data, in response to the power-consumption reduction request.