In Aurora, one project can have multiple designs. Each design refers to a specific configuration of electrical components that will make up the PV system. Aurora allows you to create multiple different designs for any given project. This allows you to experiment with different PV systems, each highlighting specific strengths. I.e. you might create one design for the most cost effective system, and one for the most energy efficient PV system. Aurora allows you to specify your primary key of a design within Aurora's system under the field external_provider_id. This allows you to map your design record to Aurora's design.