The increasing of Zero Energy Building (ZEB) introduction leads to the need of energy management in building. Utility supply is still necessary to avoid the load curtailment. In this case, electricity prices may affect the economical operation of building. Recently, it becomes common for utility to use time-varying prices, and give options for customer to choose between fixed prices or time-varying prices. In this study, we introduced peak-time price ratio, α, and peak-base ratio parameter, β, to identify electricity pricing plan. These parameters are used to evaluate the system benefit which is intended to be applied in preliminary economic study of system planning. By using a general model of power grids system which contains PV generation and battery system as energy storage, the parameters will be validated. The contribution is to be used for evaluating the system benefit which is intended to be applied in preliminary economic study of zero energy building system planning.