Smart Grid is a next generation intelligent grid that optimizes the energy efficiency and enhances trust and transparency. The electricity providers and consumers exchange real-time information by combining information technology to existing grid.
 Based on real-time pay plan, customers can flexibly adjust electricity usage by the plan and this system uses renewable energy sources such as solar power, wind power and fuel cells and power saving devices in the daytime, when the rate of electricity is high and use electrify in the morning and and night, when the rate of electricity is low, to reduce the energy bill and use excess power in the peak hours.