Jayanta Kapat

Abstract

Researchers at the University of Central Florida have invented a revolutionary way for existing fossil fuel-fired power plants to significantly reduce their maintenance costs, reduce greenhouse gas emissions and produce even more electricity in the process. By simply retrofitting their turbine systems with UCF's specially designed recuperators and hot gas path components, companies can operate at peak efficiency much longer and harness their CO₂ exhaust gas to operate a supercritical carbon dioxide (S-CO₂)-based power cycle to increase energy production. Made of a unique polymer-derived ceramic composite (PDCC) material, the new components are smaller, lighter, and much stronger than traditional hot gas path components and recuperators.

Technical Details

The invention consists of a power generation system that includes a turbine with ceramic-based recuperators (heat exchangers) and hot gas path components (such as combustion liners, transition pieces and sealings). All components are made of an innovative, inexpensive PDCC material. Compared to superalloys found in turbines today, PDCC fibers have twice the strength and can handle much higher operating temperatures (more than 2,200 F). The invention also comprises configurations for high and low temperature recuperators, each with multiple matrix panels that interconnect to define hot and cold fluid channels. For example, the hot fluid channels can be adjacent to cold fluid channels and arranged in a counterflow and stair-step configuration. Companies can use the invention to retrofit both closed and semi-closed Brayton power generation systems.

Benefit

Market Application

Abstract

The University of Central Florida invention is a hydrogen-oxygen storage mechanism integrated with an H2/O2-sCO2 direct-fired power cycle enabling long-time energy storage and high-efficient reconversion of electricity from the storage medium. Current power cycle systems are designed to produce cheap energy for the commercial, residential, or industrial sector, which maximizes the use of fuel. However, with increasing energy production, there is associated pollution and CO2 emission. Renewable energy sources such as wind and sun can be fossil-free energy alternatives. Still, the intermittent nature of these sources requires rebalance of the production and consumption of the power grid.

Benefit

Market Application

Publications

A Novel Long-Duration Hydrogen Storage Concept Without Liquefaction and High Pressure Suitable for Onsite Blending, Proceedings Paper, Turbo Expo: Power for Land, Sea, and Air; The American Society of Mechanical Engineers, June 7-11, 2021.

Abstract

Researchers at the University of Central Florida have developed two technologies for catalytically cracking ammonia into hydrogen as a fuel source. The technologies enable ammonia to be both a carrier of hydrogen as fuel and to provide cooling for compressor intercooling. Their use also helps to eliminate nitrogen oxides (NOx), air-polluting chemical compounds that form smog, ozone and acid rain. Compared to hydrogen storage, ammonia has advantages for volumetric energy density, safety, and the supply chain. Example applications include aircraft, land or water vehicles and power generation.

Technical Details:

• Ammonia-Hydrogen Cracking Device with Integrated Topology-Optimized Heat Exchanger (technology # 2023-016): Instead of burning ammonia directly, the UCF device catalytically cracks ammonia into hydrogen. With the technology, ammonia is a carrier of electricity-derived, green hydrogen for aviation, with near-zero emissions. The alternative aircraft fuel can compete with sustainable aviation fuels (SAFs) and hydrogen. With its non-coking properties, ammonia makes it a suitable heat sink for intercooling compressor air. Researchers adapted performance data of an existing aircraft engine for a modern narrow-body aircraft to the novel fuel concept. An intercooler was sized based on expected operating conditions on the ground and during flight.
• Combustion Liner with Integrated Cooling Channels for Ammonia Cracking (technology # 2024-021): Hydrogen-enabling can crack ammonia within the combustion liner. Gas turbines exhibit higher cycle efficiencies with increasing combustion temperatures, whether for power generation or aviation. Combustion liners, a crucial part of the combustion system, contain the flame and are exposed to some of the highest temperatures within gas turbine systems. They are actively cooled using compressor bleed air. Though viewed as an emerging fuel and hydrogen carrier to cut carbon emissions, ammonia is typically not combusted directly but rather cracked into hydrogen and nitrogen using a process that requires extensive energy and high temperatures. As a solution, the UCF technology involves cracking ammonia within the combustion liner, reducing the coolant requirement of the system. It also improves performance and durability while providing high heat levels at elevated temperatures for cracking. Internal or external channels coated with a catalyst act as cracking-promoting surfaces while cooling the combustion liner. The channels may or may not be additively manufactured and may or may not have turbulence-promoting features such as ribs, pins, or other engineered roughness.
  
  Partnering Opportunity: The research team is looking for partners to develop the technology further for commercialization.

Benefit

Market Application