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Uysal, Selcuk Can

Publications and source records attributed to Uysal, Selcuk Can.

10 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Hydrogen and Power Co-Production Using Direct sCO 2 Power Cycles

This report presents the techno-economic analysis (TEA) results of integrating a modified autothermal reforming (ATR) hydrogen (H 2 ) production plant with a natural gas-fired, utility-scale power plant based on the direct supercritical carbon dioxide (sCO 2 ) power cycle. In this study, the H 2 production and the power plant are fully integrated in terms of heat, fuel, and carbon capture and storage (CCS). The ATR process has significant waste heat available for heat integration with a direct-fired sCO 2 power plant that benefits the power plant efficiency. The off-gas stream from the modified ATR process is primarily carbon dioxide (CO 2 ), carbon monoxide (CO), and residual H 2 . As supplemental fuel, it has beneficial heating value in the CO and H 2 that can be used in the direct sCO 2 power cycle. Finally, the direct sCO 2 power plant can isolate the CO 2 produced at the facility for CCS.

08 HYDROGEN↗
DOE OSTI2023

Cooled Gas Turbine and Combined Cycle Analysis for H 2 -CH 4 Fuel Mixes (Up to 100% H 2 )

In this study, a cooled gas turbine analysis was conducted for varying levels of hydrogen (H 2 ) blends with the natural gas. The ultimate goal is to have a gas turbine design that can be used for all the fuel blends (including 100% H 2 ) without any changes to the system. The technological developments in the cooling system, gas turbine design and materials that will be required for H 2 combustion were identified and analyzed in this study to develop an advanced gas turbine design for H 2 fuels. The study includes a combined cycle performance analysis with the H 2 fuel blends using the advanced gas turbine design developed in this study. A techno-economic analysis was conducted for analyzing the impact of the H 2 fuels on the levelized cost of electricity and cost sensitivities to fuel price and capacity factor.

03 NATURAL GAS↗
DOE OSTI2022

Advanced Turbine Airfoils for Efficient CHP Systems: Energy Storage Integration Analysis

This report documents the energy storage systems (ESS) integration portion of the work conducted under the Office of Energy Efficiency and Renewable Energy (EERE) advanced Manufacturing Office (AMO) Lab Call DE-LC-000L059 project titled "Advanced Turbine Airfoils for Efficient CHP Systems." The objective of this work is to analyze the previously-developed combined heat and power (CHP) plant with the upgraded gas turbine to include an ESS to improve the operational flexibility. The analysis includes identifying a candidate CHP configuration for the ESS integration and identifying possible storage systems to be integrated. A qualitative analysis was made to down select possible storage technologies and a techno-economic analysis (TEA) was made for the CHP system with the selected storage technology.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2022

Performance and Cost Potential for Exemplar Direct Supercritical Carbon Dioxide Natural Gas Plants

This report presents the techno-economic analysis (TEA) optimization results of natural gas-fired utility-scale power plants based on the direct supercritical carbon dioxide (sCO 2 ) power cycle. To identify optimum plant configuration, the study also considered three different cases (Case A, Case B, Case C) with varying levels of thermal integration with the plant air separation unit (ASU). A fourth case (Case D), which is based on a patent from 8 Rivers, was also considered and includes thermal integration with the ASU as well as compressed recycle carbon dioxide (CO 2 ) gas. The four direct sCO 2 power plants offered similar or slightly higher plant efficiencies than the reference NGCC plants based on an F-class gas turbine with carbon capture and storage (CCS). LCOE of the direct sCO 2 plants is 13.5–17.2 percent higher than the reference NGCC plants with CCS due to higher capital costs associated with the ASU and sCO 2 power block. Recuperators make up over 50 percent of the power cycle costs. Consequently, any research and development (R&D) efforts to reduce the recuperator capital costs will be beneficial for the technology commercialization. The study also investigated the impact of co-firing landfill gas (LFG) and natural gas on plant efficiency, LCOE, and CO 2 emissions. Increasing the LFG co-firing from 0 percent to 50 percent (mass basis), decreased the plant efficiency by 0.3 percentage points and increased the LCOE by 3 percent. Due to high inherent CO 2 capture rates, direct sCO 2 plants have strong potential to achieve net-zero CO 2 emissions with LFG and natural gas co-firing.

03 NATURAL GAS↗
DOE OSTI2021

Radial Compressor Design and Off-Design for Trans-critical CO2 Operating Conditions

Presentation for the The 7th International Supercritical CO2 Power Cycles Symposium, February 21 – 24, 2022, San Antonio, Texas. A multi-staged intercooled centrifugal compressor design is performed for an indirect-fired sCO2 cycle and the design point data are used to generate the performance maps using a 2D mean-line analysis code. Fluid and turbomachinery similarity laws are applied to find an appropriate surrogate ideal gas fluid to be used in the design and performance map generation codes. The performance maps are then scaled back for the sCO2 fluid case using the affinity laws.

Uysal, Selcuk Can↗
DOE OSTI2021

Radial Compressor Design and Off-Design for Trans-critical CO2 Operating Conditions

A multi-staged intercooled centrifugal compressor design is performed for an indirect-fired sCO2 cycle and the design point data are used to generate the performance maps using a 2D mean-line analysis code. Fluid and turbomachinery similarity laws are applied to find an appropriate surrogate ideal gas fluid to be used in the design and performance map generation codes. The performance maps are then scaled back for the sCO2 fluid case using the affinity laws. The developed methodology is validated using the experimental data for a compressor operating at similar inflow conditions.

Uysal, Selcuk Can↗
DOE OSTI2021

Impact on Cycle Efficiency of Small Combined Heat and Power Plants from Increasing Firing Temperature Enabled by Additive Manufacturing of Turbine Blades and Vanes

The results of this study show that a 180°F (100°C) increase in firing temperature can increase the gas turbine efficiency by 1 percentage point without improving cooling effectiveness and add 2 additional percentage points in efficiency by using advanced turbine blades with higher internal cooling efficiency. The engine upgrades evaluated in this study show potential for increasing the CHP cycle efficiency by 3 percentage points while increasing the steam generation rate by 8%.

Uysal, Selcuk Can↗
DOE OSTI2021

Impact on Cycle Efficiency of Small CHP Plants from Increasing Firing Temperature Enabled by AM of Turbine Blades

Combined Heat and Power (CHP) systems are gaining popularity because of their potential for high overall thermodynamic efficiency and increased need for distributed power generation. Most CHP systems include a gas turbine for electricity generation and a heat recovery steam generator (HRSG) for steam generation. The steam can be used to power a steam turbine for additional electricity generation or to drive rotating equipment, for space heating, for absorption chillers, etc. A CHP cycle configuration is often driven by the ‘principal’ utility for the facility that it services; steam or electricity. In either case, performance improvements in the gas turbine have the potential to increase the steam and power output from the cycle, which is a direct result of improvements in the gas turbine efficiency and power output. One possible opportunity to improve an existing gas turbine’s performance is to increase the firing temperature with improved turbine cooling and increased compression ratio.<br>In this study, the impact on CHP cycle performance from increasing the turbine firing temperature by 100 °C and improving the turbine blade cooling for a 6-MW scale gas turbine is estimated using an analytical cooled gas turbine model and a steam cycle model. A sensitivity analysis was performed to understand the impact of increasing the internal cooling effectiveness, thermal barrier coating performance and blade material upgrades on gas turbine and CHP cycle efficiency. The impacts of turbine blade cooling improvements were studied for three common CHP cycle configurations identified from the literature. Various definitions for CHP cycle efficiency from the literature are used in the comparisons. The results showed that a 100 °C increase in firing temperature can increase the gas turbine efficiency by 1 percentage point without improving cooling effectiveness and add 2 additional percentage points in efficiency by using advanced turbine blades with higher internal cooling efficiency. Studied engine upgrades showed potential for increasing the CHP cycle efficiency by 3 percentage points while increasing the steam generation rate by 8%.<br>

Uysal, Selcuk Can↗
DOE OSTI2021

Comparative Study for Pressure Gain Combustion-Gas Turbine System Performance in NGCC Configurations

The Department of Energy (DOE) has a goal to increase natural gas combined cycle (NGCC) plant efficiency to greater than 70 percent on a lower heating value (LHV) basis. Improvement in gas turbine (GT) efficiency is key achieving this goal. While many of the traditional improvement methods (higher firing temperature, advanced materials, improved cooling methods, etc.) may increase current GT and NGCC efficiencies incrementally, combining these traditional advancements with breakthrough technologies such as pressure gain combustion (PGC) may provide significant system efficiency gains. PGC is a combustion process that results in a net pressure increase across the combustor (up to pressure ratio of 2.2) rather than the traditional (<5%) pressure drop. There are multiple PGC technologies being developed that create the pressure rise phenomena, including resonant pulse combustors (RPCs), pulse detonation engines (PDEs), wave rotor combustor (WRC) engines and rotating detonation engines (RDEs). In this study, scoping analyses of PGC concepts applied to NGCC power plants were performed by combining simplified analytical models for the RPC, PDE, WRC, and RDE types of pressure gain processes with a GT model to evaluate impacts of using each of the PGC technologies on key GT performance parameters. Sensitivity analyses were also performed. Ultimately, the PGC technologies were found to have the potential to increase simple cycle efficiency by 4–6 percent (absolute) and NGCC efficiency by 2–3 percent (absolute) based on the results of the current study.

03 NATURAL GAS↗