Planning and engineering method for a process plant with which - in a plant planning phase, a flow chart of the plant is compiled by means of a plant planning tool by linking graphic process objects representing operator-controllable and observable facilities of the plant, - in a simulation phase, the linked process objects of the plant or a part of the plant are imported by means of a simulation tool and the process in the plant or the part of the plant is simulated with reference to simulation models assigned to the imported process objects, - in an engineering phase, an engineering tool is used to compile a function chart of the plant by linking icons of function blocks, wherein each process object has a corresponding automation function block describing the automation function of the process object and - the automation function blocks are loaded into automation devices of the plant for implementation, wherein - for at least a part of the process objects representing electrically operated facilities of the plant, the assigned simulation models are each supplemented by an energy consumption model describing the electrical energy consumption of the facility as a function of measurable or known process variables in the plant, - in the simulation phase, the electrical energy consumption of the facilities represented by the imported process objects is simulated and - for process objects for which the assigned simulation models are supplemented by an energy consumption model, the corresponding automation function block is supplemented by an energy consumption function which is derived by specialisation from the energy consumption model and is embodied to estimate the current electrical energy consumption of the facility during its running time in the plant. - in a plant planning phase, a flow chart of the plant is compiled by means of a plant planning tool by linking graphic process objects representing operator-controllable and observable facilities of the plant, - in a simulation phase, the linked process objects of the plant or a part of the plant are imported by means of a simulation tool and the process in the plant or the part of the plant is simulated with reference to simulation models assigned to the imported process objects, - in an engineering phase, an engineering tool is used to compile a function chart of the plant by linking icons of function blocks, wherein each process object has a corresponding automation function block describing the automation function of the process object and - the automation function blocks are loaded into automation devices of the plant for implementation, wherein - for at least a part of the process objects representing electrically operated facilities of the plant, the assigned simulation models are each supplemented by an energy consumption model describing the electrical energy consumption of the facility as a function of measurable or known process variables in the plant, - in the simulation phase, the electrical energy consumption of the facilities represented by the imported process objects is simulated and - for process objects for which the assigned simulation models are supplemented by an energy consumption model, the corresponding automation function block is supplemented by an energy consumption function which is derived by specialisation from the energy consumption model and is embodied to estimate the current electrical energy consumption of the facility during its running time in the plant. - for at least a part of the process objects representing electrically operated facilities of the plant, the assigned simulation models are each supplemented by an energy consumption model describing the electrical energy consumption of the facility as a function of measurable or known process variables in the plant, - in the simulation phase, the electrical energy consumption of the facilities represented by the imported process objects is simulated and - for process objects for which the assigned simulation models are supplemented by an energy consumption model, the corresponding automation function block is supplemented by an energy consumption function which is derived by specialisation from the energy consumption model and is embodied to estimate the current electrical energy consumption of the facility during its running time in the plant.