Plug-in electric vehicles as storage devices within an Autonomous power system. Optimization issue

In modern Power Electric Systems (PES) consisting of diverse sources of energy supply, uncertainty regarding the availability of some renewable sources-based generation plants is one of the major issues affecting the task of sizing the capacity of conventional generation plants. Energy storage devices are able to mitigate the intermittence of the availability of renewable resources and, consequently, successfully reduce the aforementioned uncertainty. Along these lines, electric drive vehicles equipped with sophisticated storage, control and communication systems are being developed and improved in order to allow their connection to the distribution networks at the final consumers´ level. This paper discusses the possibilities of taking advantage of plug-in electric vehicles while they are parked provided that their energy storage system installed on board is able to consume from or rapidly supply energy into the electric grid. The impact of incorporating plug-in electric vehicles within an Autonomous PES (APS) is evaluated by modeling the dynamic decisions executed for the EMS and by formulating an optimization problem where the type and size of the diverse generation plants -conventional and renewable- are known and the penetration level of plug-in electric vehicles is determined. Solutions found involve maximizing the performance (expressed in monetary terms) of the tested APS.