Session: 04-01: Research for the Clean Energy Transition I

Paper Number: 130180

130180 - From Waste to Resource: A Techno-Economic Evaluation of a CO2 Heat Pump and ORC Combined System With Photovoltaic Integration and Thermal Storage 

Abstract: 

The escalating global energy demand has resulted in a corresponding increase in greenhouse gas emissions. In order to cut those emissions, multiple energy sources, of various quality levels and forms, must be developed. One promising approach involves the utilization of low-grade waste heat generated by industrial processes. This study investigates a novel combined heating and power (CHP) generation approach through a comprehensive techno-economic analysis of a hybrid system that combines a CO₂ heat pump (HP) and an organic Rankine cycle (ORC) for utilizing low-grade waste heat. The HP is powered by photovoltaics (PV), enabling the extraction of heat from low-grade sources sustainably, and is further integrated with sensible thermal energy storage (TES) for demand management. The system primarily aims to supply district heating, but in scenarios with reduced district heating demand, it seamlessly transitions to an ORC-based power generation mode. The integration of PV, HP, ORC, and TES allows for the efficient utilization of diverse waste heat sources, with adaptability to various operational strategies and applications contingent upon demand and supply dynamics. A mathematical model of the hybrid CHP system is developed and simulated using the Python programming language. The study's techno-economic and parametric analysis explores component and system-level performance with Miami, FL serving as a case study. The outcome of this study highlights the potential of hybrid CHP systems for sustainable and versatile energy solutions.

Presenting Author: Laura Schaefer Rice University

Presenting Author Biography: Dr. Laura Schaefer is the Burton J. and Ann M. McMurtry Professor in the Department of Mechanical Engineering at Rice University. She received a B.S. in Mechanical Engineering (1995) and a B.A. in English (1995) from Rice University, and her M.S. (1997) and Ph.D. (2000) degrees in Mechanical Engineering from the Georgia Institute of Technology. She was formerly a faculty member in Mechanical Engineering at the University of Pittsburgh from 2000-2015, where she was Deputy Director of the Mascaro Center for Sustainable Innovation, and Associate Director of the Center for Energy. She is an ASME Fellow, and a past Chair of the Advanced Energy Systems Division of ASME.

Authors:

Kashif Liaqat Rice University
Shima Soleimani Rice University
Sophie Leibowitz Rice University
Jörg Temming Flowserve Corporation
Heiner Kösters Flowserve Corporation
Laura Schaefer Rice University