System imbalance minimizing renewable generation portfolio selection in the presence of plug-in electric vehicles

We have developed a model for analyzing the system imbalance with different mixes of renewable generation (solar photovoltaic and wind) including in the presence of large pools of plug-in electric vehicles (PEVs) that participate in vehicle-to-grid and grid-to-vehicle operations. Our proposed model also identifies optimal compositions of renewable portfolios that minimize system imbalance reserve requirements under various target penetration levels for renewable power in conjunction with growing deployment of PEVs. We have applied our model to 4 years of actual load, solar and wind resource data for New York City to derive the trends in system imbalance with growing renewable and PEV penetrations. Our results show that by optimizing the renewable mix, imbalance reserve requirements can be cut down by about 60% for target renewable penetrations above 30%. Adding PEVs to the optimization scheme enhances the reduction further to 75%. This represents an economic benefit of 2.2 million per year.