CURENT Power and Energy Industry Seminar – Dr. Jim Ostrowski
Date: Friday, September 14, 2018
Time: 12:20 – 1:10pm EST
Location: Room 404, Min H. Kao Building, Knoxville, TN
Title: Optimization Methods for the Unit Commitment Problem
Presenter: Dr. Jim Ostrowski, University of Tennessee
Abstract: The unit commitment problem (UC) is that of scheduling generators to meet power demand, and has been one of the great successes of mixed-integer programming models. The Midwest Independent Transmission System Operator (MISO), recipient of the Edelman Award in 2011, reports annual savings of over $500 million by using MIP models over Lagrangian relaxation techniques for unit commitment. Because of the scales involved, a 1% savings in energy markets is greater than $10 billion annually. We present a perfect formulation for a single generator in the unit commitment (UC) problem. This generator can have characteristics such as ramping constraints, time-dependent start-up costs, and start-up/shut-down ramping. The perfect formulation is polynomially large, so we use it to create a cut-generating linear program for a single generator. We test the computational efficacy of these cuts in a utility-scale UC MIP model, based on the FERC generator set and 2015 hourly data from PJM, creating 362 24-hour UC instances. We find that although these cuts from the ramping polytope are not very helpful for today’s UC problems, they may be more beneficial for tomorrow’s. We will also show how to extend these results to settings where there are nearly identical generators.
Bio: Dr. Jim Ostrowski is an associate professor in the Industrial and Systems Engineering department at the University of Tennessee. His research focuses on both applied and theoretical aspects of optimization. With respect to power systems, he has been working with the Midcontinent Independent System Operator (MISO) to improve solution times to their day ahead unit commitment problem. His work has been funded by the NSF, industry (MISO), and the DOE (as one of their early career awardees).