Copyright by Benjamin Houston Gully 2012 The Dissertation Committee for Benjamin Houston Gully certifies that this is the approved version of the following dissertation: Hybrid Powertrain Performance Analysis for Naval and Commercial Ocean-Going Vessels Committee: Michael E. Webber, Supervisor Carolyn C. Seepersad, Supervisor Robert E. Hebner Thomas M. Kiehne Dongmei (Maggie) Chen Hybrid Powertrain Performance Analysis for Naval and Commercial Ocean-Going Vessels by Benjamin Houston Gully, B.S.M.E., M.S.E. DISSERTATION Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY The University of Texas at Austin August 2012 Dedicated to my loving parents, John Houston Gully and Rajean Meester Gully, for their infinite support and the opportunity to devote my efforts to research that I hope can provide for the common good. Acknowledgments I would predominantly like to thank Dr. Michael E. Webber and Dr. Carolyn C. Seepersad for their guidance, continued support and good faith. I would also like to thank Dr. Bob Hebner at the UT Center for Electromechanics for his support and allowing me to carve my own path. Furthermore, this work would not have been possible without the technical guidance of Dr. Tom Kiehne, Dr. Hamid Ouroua, Dr. Angelo Gatozzi, John Herbst and Richard Crawford. This work was supported by the Office of Naval Research through its Electric Ship Research and Development Consortium. v Hybrid Powertrain Performance Analysis for Naval and Commercial Ocean-Going Vessels Benjamin Houston Gully, Ph.D. The University of Texas at Austin, 2012 Supervisors: Michael E. Webber Carolyn C. Seepersad The need for a reduced dependence on fossil fuels is motivated by a wide range of factors: from increasing fuel costs, to national security implications of supply, to rising concern for environmental impact. Although much focus is given to terres- trial systems, over 90% of the world's freight is transported by ship. Likewise, naval warfighting systems are critical in supporting U.S. national interests abroad. Yet the vast majority of these vessels rely on fossil fuels for operation. The results of this thesis illustrate a common theme that hybrid mechanical-electrical marine propulsion systems produce substantially better fuel efficiency than other technologies that are typically emphasized to reduce fuel consumption. Naval and commercial powertrains in the 60{70 MW range are shown to benefit substantially from the utilization of mechanical drive for high speed propulsion; complemented by an efficient electric drive system for low speed operations. This hybrid architecture proves to be able to best meet the wide range of performance requirements for each of these systems, while also being the most easily integrated technology option. Naval analyses eval- uate powertrain options for the DDG-51 Flight III. Simulation results using actual operational profile data show a CODLAG system produces a net fuel savings of up to 12% more than a comparable all-electric system, corresponding to a savings of 37% relative the existing DDG-51 powertrain. These results prove that a mechanical vi linkage for the main propulsion engine greatly reduces fuel consumption and that for power generation systems requiring redundancy, diesel generators represent a vastly superior option to gas turbines. For the commercial application it is shown that an augmented PTO/PTI hybrid system can better reduce cruise fuel consumption than modern sail systems, while also producing significant benefit with regard to CO2 emis- sions. In addition, using such a shaft mounted hybrid system for low speed electric drive in ports reduces NOX emissions by 29{43%, while CO is reduced 57{66% and PM may be reduced up to 25%, depending on the specific operating mode. As an added benefit, fuel consumption rates under these conditions are reduced 20{29%. vii Table of Contents Acknowledgments v Abstract vi Glossary of Acronyms xi List of Tables xiii List of Figures xv Chapter 1. Introduction 1 1.1 Naval Propulsion Systems Background . .3 1.2 Commercial Ship Performance Requirements . .4 1.3 Comparative Analysis of Propulsion System Configurations . .5 1.4 Document Organization . .8 Chapter 2. Background and Related Publications 9 2.1 Existing Electrified Naval Propulsion Systems . 11 2.1.1 All-Electric Navy Vessels . 11 2.1.2 Modern Hybrid Naval Power Systems . 13 2.2 DDG-51 Flight III Powertrain Analyses . 18 2.2.1 CrossConnect System Evaluation Studies . 19 2.2.2 Hybrid Architecture Redesign Analyses . 24 2.3 Commercial Ship Propulsion Background . 29 2.3.1 Commercial Ship Propulsion Systems . 31 2.3.2 Alternative Energy Systems Integration . 33 2.4 Summary . 37 Chapter 3. System and Component Model Development 39 3.1 Technical Differences in Marine Powertrain Architectures . 39 3.2 Propulsion Technology Modeling Bases . 41 3.2.1 Naval Prime Mover Selection and Modeling . 44 3.2.1.1 Navy Auxiliary Power Generating Units . 47 viii 3.2.2 Commercial Prime Mover Representation . 48 3.2.3 Electric Machines . 51 3.3 Alternative Energy Utilization . 53 3.3.1 Solar Energy Technology Representation . 55 3.3.2 Modern Sail System Technologies . 57 3.3.2.1 Rigid Wing Sail . 57 3.3.2.2 Fletter Rotor Sail Devices . 63 3.3.2.3 SkySails High Altitude Kite . 73 3.3.3 Wind Profile Definition . 80 3.4 Operational Analyses . 81 3.4.1 DDG-51 Load Profile . 84 3.4.2 Commercial Load and Operational Profiles . 87 3.5 Summary . 92 Chapter 4. US Navy Suface Ship Evaluation 94 4.1 Base DDG Powertrain Analysis . 94 4.2 Hybrid Electric Powertrain Concept . 97 4.2.1 Electric Power Generation System Deisgn . 99 4.2.2 Propulsion Gas Turbine Selection . 101 4.3 Powertrain Architecture Comparative Analysis . 102 4.3.1 Hybrid Powertrain Alternative 1: GE LM2500+G4 . 102 4.3.2 Hybrid Powertrain Alternative 2: Rolls-Royce MT30 . 105 4.3.3 Spatial Constraint Assessment . 109 4.4 Performance Comparison of CODLAG System with All-Electric IPS . 112 4.5 Operations Based Fuel Consumption Comparison . 116 4.6 Electric Power System Redundancy Concepts . 118 4.6.1 Additional Potential Benefits of Hybrid Drive Systems . 122 4.6.1.1 Single Generator Operation for COGLAG Architectures 125 4.7 Discussion . 132 Chapter 5. Commercial Application Analysis 134 5.1 PTO Based Hybrid Drive Performance Analysis . 134 5.1.1 Fuel Consumption Benefits of PTO Systems . 135 5.1.2 Hybrid Electric Propulsion Performance Analysis . 136 5.2 Alternative Energy Comparison . 140 5.2.1 Solar Panel Power Generation . 141 5.2.2 Sail Propulsion Systems Analysis . 143 ix Chapter 6. Summary of Results 152 6.1 Navy Specific Conclusions . 152 6.2 Commercial Ship Specific Conclusions . 154 6.3 Research Contributions . 155 6.4 Future Work . 156 Appendices 157 Appendix A. DDG-51 Speed Profiles and CONOPS Data 158 Appendix B. Fuel Calculation Methodology 162 Bibliography 175 x Glossary of Acronyms AIM - Advanced Induction Motor AMDR - Air and Missile Defense Radar CCI - Command, Control and Indication CODLAG - Combined Diesel-Electric and Gas COGLAG - Combined Gas-Electric and Gas DG - Diesel Generator EM - Electric Machine ESS - Energy Storage System GTG - Gas Turbine Generator HFAC - High Frequency Alternating Current HFO - Heavy Fuel Oil IPS - Integrated Power System (All-Electric) LaWS - Laser Weapon System MAN - Maneuver (in-port ship mode) MCR - Maximum Continuous Rating MDO - Marine Diesel Oil MRG - Main Reduction Gear PDE - Propulsion Diesel Engine PGT - Propulsion Gas Turbine xi PTI - Power Take-In PTO - Power Take-Off RSZ - Reduced Speed Zone (in-port ship mode) SFC - Specific Fuel Consumption SGO - Single Generator Operation TEU - Twenty-foot Equivalent Unit xii List of Tables 2.1 A sample comparison study for PGT selection which uses a ranking system for component technology selection. 26 3.1 Constant values used in the polynomial fit for the Rolls-Royce MT30 provide for fuel consumption calculations. 46 3.2 Constant values used in the polynomial for the Sulzer 12RTA96C pro- vide for fuel consumption calculations. 49 3.3 Constant values used in the polynomial for the commercial ship auxil- iary power MaK M32 DG fuel consumption calculations. 50 3.4 Emissions are calculated based rates typical of each engine's class and speed rating. 50 3.5 Geometric specifications for the Flettner rotor lift data sets shown in Figure 3.16. 67 3.6 Geometric specifications based on one of Skysails standard high-altitude kite used in analysis. 75 3.7 Speed and auxiliary load factors define the necessary aspects of a com- mercial vessel's operational profile, average values were assumed (* = defined by ship design). 91 4.1 A comparison of generator alternatives shows HFAC systems can pro- duce much more power in the same footprint as the current AG9140. 100 4.2 A comparison of generator alternatives shows HFAC systems can pro- duce much more power in the same footprint as the current AG9140. 102 4.3 Calculating potential EM size by fitting similar units into the LM2500 footprint suggests a maximum potential length of 2.13 m. 111 4.4 Comparing PGT and EM system dimensions to the outgoing LM2500 unit and engine room dimensions suggests minimal fitment issues. 112 4.5 HFAC MT30 specifications used for nominal IPS system. 113 4.6 Simulation results show very significant reductions in fuel consumption for the IPS and even better for the CODLAG hybrid, with monetary figures based on 4000 operating hours per year, and F-76 at $100/bbl. 117 4.7 Total annual fuel consumption based on indicated operational profile data assuming 4000 hours at sea per year. 118 4.8 Simulation results including COGLAG systems show that GTG aux- iliary power units greatly increase fuel consumption and that SGO is necessary for them to improve fuel consumption rates.