A system for monitoring electric energy amount according to one embodiment of the present disclosure includes an electric energy system including one or more loads receiving electric energy through an external electric energy source and a renewable energy generator, a home server for receiving information of a first electric energy amount that is an electric energy amount consumed by the one or more loads, a second electric energy amount that is supplied from the external electric energy source to the electric energy system, and a third electric energy amount that is supplied from the renewable energy generator to the electric energy system, and an electric energy amount monitoring server calculating the second electric energy amount or the third electric energy amount from electric energy consumption of the electric energy system, which is received from the home server, and supply electric energy amount information supplied to the electric energy system.