Optimization-Based Management of Energy Systems

Abstract : Why Distributed Power Systems and Energy Microgrids?: security of energy supply and reduced energy costs and environmental impact. Energy microgrids are distributed power systems with the capability to work seamlessly in islanding and grid-connected modes. They include thermal and electrical systems. Key Results: feasible microgrid architectures are able to provide 50-60% annual operating cost reduction, and optimization-based supervisory microgrid control provides an average annual 5-20% cost reduction compared with simple rule-based control strategy. Energy Management System (EMS) performs effective coordination and dispatching of distributed energy resources -- functionally similar to economic dispatch and unit commitment in power systems, selects combination of sources and storage to meet demand, considers constraints on availability of supply and operational limitations, and interfaces with customers and utilities. Conventional dispatching systems are optimization-based and use steady-state models. Renewable intermittency and memory associated with storage require planning and forecasting. Systematic decision-making with uncertainties in demand and availability of renewable resources. Conclusions: stochastic programming helps with decision making under uncertainty; stochastic programming tools can drastically reduce the value of perfect information; and sizing, architecture, and magnitude of loads dictate the required accuracy of forecasts.