Environmental and economical optimization of microgrid long term operational planning including PV-based active generators

Large scale penetration of Renewable Energy-Based Generators (REBG) and Distributed Energy Resources (DER) requires an evolution of the classical dispatching of conventional generators in power systems. A step towards the Smart Grid is to integrate locally REBG, conventional generators and loads in clusters called microgrids. This paper presents a microgrid energy management optimization in the presence of PV-based active generators. Based on predictions of the available energy from PV generators, energy storage availability and the power demand from the loads, the Microgrid Central Energy Management System (MCEMS) elaborates a 24 hour ahead operational planning using the approach of unit commitment by dynamic programming. The optimization objective function is either the CO₂ equivalent emissions (environmental criteria), the fuel consumption (economical criteria) or a tradeoff between these two. In order to reduce uncertainty in forecasted values for PV production or load demand, a medium term energy management recalculates the generators power references one hour ahead if necessary.