CH-24-C015 - CHP Digital-Twin-Model for Control, Optimization and Transition to Renewable Based Fuels

Combined heat and power (CHP) systems are an efficient means of producing electrical power and heating energy to aid in decarbonization efforts. These systems generate electricity and thermal energy primarily used in building systems, while capturing energy in waste heat that is normally lost in traditional generation systems. Developing more efficient control strategies and optimization methods for current CHP systems will assist in improving grid resilience as well as easing the integration of renewable energy generation systems. Furthermore, Digital-Twin-Models of CHP systems will help transition these systems from using natural gas to hydrogen generated from renewable energy. The University of Texas (UT) at Austin utilizes a CHP plant that produces all the campus’ electrical and heating needs in conjunction with a microgrid and steam tunnel distribution system. The CHP is closely monitored and provides high frequency data from all components. Here, a model of the campus CHP system is developed and validated using measurement data provided by the utilities office. System component models predict performance of CHP components such as gas turbine generator, steam turbine generator, heat recovery steam generator, and steam boiler. A system of equations is developed to close the model, and optimization parameters are identified (developing the CHP digital twin). For the optimization, real energy consumption from 160 campus buildings, including electricity for building and district cooling systems and steam for district heating is used. A case study is performed studying the effects of renewable energy integration into an existing campus CHP plant, and results are presented to discuss potential challenges that need to be overcome during integration.