NOVELTY - The method involves receiving information pertaining to an energy generation system i.e. solar photovoltaic system (800), to be installed at a customer site from a user by a computer system. An electrical design for installing the energy generation system is determined at the customer site by the computer system based on the information, another information retrieved from external data sources, an electrical data model and a decision tree modeling an electrical design process. An installation diagram illustrating the determined electrical design is generated by the computer system.    USE - Method for facilitating an electrical design of a renewable energy generation system i.e. solar photovoltaic system (claimed) installed at a residential and non-residential customer site. Can also be used for wind turbine system, solar-thermal system, geothermal system, biomass system and hydro-power system.    ADVANTAGE - The method enables eliminating the need for an experienced engineer or system designer to manually select an electrical component of a system installation, or manually determine how the components can be interconnected, so that the electrical design process can be performed more quickly and efficiently, thus eliminating need for training or experience on the part of the designers. The method enables providing default values to be displayed as read-only values in interface, thus preventing the user from making any changes. The method enables providing the default values to be modifiable, thus enabling the user to override the defaults with alternative values. The method enables providing electrical design module that can automatically attempt to retrieve from external data sources if the necessary information does not provided, so that the electrical design module can minimize the need for user input when generating the electrical design.    DETAILED DESCRIPTION - The information is main panel information, utility meter information and grounding configuration information. The computing system is an end-user computing device such as desktop computer, laptop computer, personal digital assistant, smartphone and tablet computer. The external data sources are selected from a group consisting of an Authority Having Jurisdiction (AHJ) database, utility database, state database and a component supply chain database. INDEPENDENT CLAIMS are also included for the following:    (1) a system for facilitating an electrical design of an energy generation system    (2) a computer-readable storage medium comprising a set of instructions for facilitating an electrical design of an energy generation system.    DESCRIPTION OF DRAWING(S) - The drawing shows a circuit diagram illustrating a method for facilitating an electrical design of an energy generation system.    Solar photovoltaic system (800)    Photovoltaic module strings (802)    Direct current combiner box (804)    Photovoltaic inverter (810)    Meter socket (812)