The U.S. Department of Energy’s (DOE) National Energy Technology Laboratory has selected six Phase II projects, to further develop innovative technologies for advanced gas turbine components and supercritical carbon dioxide (sCO2) power cycles. The projects were selected from eleven projects that participated in Phase I that was recently completed by private sector companies.

The six Phase II projects will receive a total of approximately $30 million of research funding from the DOE over the next 3.5 years.

In a combined-cycle power plant, a gas turbine generates electricity while its exhaust provides heat to a steam Rankine cycle to generate additional electricity. Current state-of-the-art combined-cycle power plants have net thermal efficiencies of approximately 61 percent (using natural gas lower heating value). Under these awards, DOE seeks to develop innovative technologies and advanced gas turbine components that will increase that efficiency to 65 percent.

The use of carbon dioxide in its supercritical state is an emerging alternative to using steam as the working fluid in a power cycle. Over the past few years, sCO2 power cycles have gained significant interest across multiple power generation applications (renewable, nuclear, and fossil energy). The use of these power cycles are attractive in comparison to steam because the thermophysical properties of sCO2 allow for higher power outputs in a smaller package. This reduced size increases efficiency and potentially reduces the cost of electricity. Two awards have been selected to develop oxy-combustion technology and turbo-expander seals to advance the state of the art for direct and indirect sCO2 power cycles.

The six projects selected for further funding are:

Rotating Detonation Combustion for Gas Turbines—Aerojet Rocketdyne (Canoga Park, CA), in partnership with the Southwest Research Institute, Purdue University, the University of Alabama, the University of Michigan, the University of Central Florida, and Duke Energy, will develop and demonstrate an air-breathing rotating detonation engine combustion system for power-generating gas turbines.

Cost—DOE: $3,942,602/Non-DOE: $2,880,882/Total Funding: $6,822,484.

Development of Low-Leakage Seals for Utility-Scale sCO2 Turbines—GE Global Research (Schenectady, NY), in partnership with Southwest Research Institute, will develop turbine end seals and inter-stage seals for utility-scale sCO2 power cycles to achieve a field-trial-ready design. The majority of the work will be focused on maturing turbine end seals by testing them in new and existing facilities at increasing pressures, temperatures, and seal sizes in both air and sCO2 environments.

Cost—DOE: $5,973,693/Non-DOE: $1,493,423/Total Funding: $7,467,116.

Cooled High-Temperature Ceramic Matrix Composite Nozzles for Gas Turbines for 65 Percent Efficiency—GE Power (Schenectady, NY), working with GE Global Research and Clemson University, will further develop high-temperature ceramic matrix composite turbine nozzles as an innovative component that will contribute to the DOE goal for advanced gas turbines.

Cost—DOE: $5,874,651/Non-DOE: $2,517,708/Total Funding: $8,392,359.

Advanced Multi-Tube Mixer Combustion for 65 Percent Efficiency—GE Power (Schenectady, NY), partnering with GE Global Research, will apply an advanced version of GE’s Micro Mixer combustion technology to enable turbine inlet temperatures in excess of 3,100 °F while minimizing NOx emissions.

Cost—DOE: $5,928,825/Non-DOE: $2,540,925/Total Funding: $8,469,750.

Ceramic Matrix Composite Advanced Transition for 65 Percent Combined-Cycle Efficiency—Siemens Energy Inc. (Orlando, FL), working with COI Ceramics and Florida Turbine Technologies will further develop a ceramic matrix composite design for Siemens’ Advanced Transition combustor in support of 65 percent efficient gas turbine combined-cycles.

Cost—DOE: $5,936,856/Non-DOE: $1,490,964/Total Funding: $7,427,820.

High-Inlet Temperature Combustor for Direct-Fired Supercritical Oxy-combustion—Southwest Research Institute (San Antonio, TX), in partnership with Thar Energy LLC, GE Global Research, Georgia Tech, and the University of Central Florida, will demonstrate a directly heated sCO2 oxy-combustor for an advanced state-of-the-art fossil-fired sCO2 power cycle.

Cost—DOE: $3,193,544/Non-DOE: $798,400/Total Funding: $3,991,944.