BIGH2 Innovation / Phase 4 – “Developing a fuel-flexible, low-carbon industrial gas turbine”

Background
In the ongoing energy transition, and for several decades to come, it will not be possible to count on specific fuels being available at all times and in large enough quantities. Security of energy supply, both in Norway and in the rest of Europe, requires that power plants are able to respond quickly and reliably to fluctuations in energy production. This is mainly due to the intrinsic unpredictability associated with the increasing share of wind and solar resources, as well as a rare but not entirely unlikely periodic reduction in rainfall with the subsequent production shortages from hydropower. Therefore, future power plants will have to provide an unhindered ability to use the fuel that is available when the need for “on-demand” large-scale power production arises.
Advanced low-NOx burners (state-of-the-art) are based on fuel and oxidant being mixed (fully or partially) prior to combustion. With current knowledge, this means that it is not possible to combine low NOx emissions with efficient combustion of hydrogen and/or ammonia. The problem lies mainly in challenges related to flame stability when using fuels with high (hydrogen) or low reactivity (ammonia). This technology gap is what the project aims to close in order to enable scenarios for industrial application of gas turbines with zero CO₂ emissions.

Goal
BIGH2/Phase IV will develop, test and demonstrate safe, efficient and clean combustion (low-NOx) of hydrogen and ammonia as carbon-free energy carriers in an advanced and state-of-the-art gas turbine combustion system as well as the unaffected ability to burn, cleanly and efficiently, natural gas as a “backup” fuel in the same combustion system. This will require a radical re-design of the gas turbine combustion system to enable axial fuel injection in two combustion stages which represents the key to achieving the desired flexibility in relation to widely different fuels (hydrogen, ammonia and natural gas). The starting point for this research work is the Siemens Distributed Combustion System (DCS) which is under development for hydrogen firing of larger “heavy-duty” gas turbines (H-class) but which will need major modifications to function optimally when firing the gas turbine with hydrogen, ammonia or natural gas (if required).

Activities
The project will increase the technological maturity of burners that have been tested and verified at laboratory scale (TRL4). This includes a full-scale demonstration of a single burner in relevant environments geared towards industrial use in a Siemens SGT750 industrial gas turbine for clean power generation both offshore and on-shore (TRL6).
The main project is organized into 3 Subprojects (SP1, SP2 and SP3). Subproject 1 (SP1) focuses on numerical modeling of the combustion system while in subproject 2 (SP2) the combustion system is investigated at laboratory scale, at atmospheric and high pressure, for clean and efficient firing of the plant with hydrogen, ammonia or natural gas. Tight integration of SP1 and SP2 activities is critically important: on the one hand, numerical simulations will contribute with important trends that reduce the costs associated with the experiments (fewer expensive runs are required in the development process), on the other hand, the experimental measurements will represent the necessary validation basis for the numerical models. Finally, subproject 3 (SP3) will consist of the actual demonstration of the technology carried out by Siemens using a full-scale version of the SGT750 combustor.

Results
The first results will consist of data from detailed numerical simulations and lab-scale experiments of the gas turbine combustion system. These initial results will be used to improve the design of the burner, which will be done in several rounds. From the start of the project, the focus will be on the first combustion stage, which should be able to handle clean and efficient combustion of ammonia. Later, the research activities will shift focus to the second combustion stage and the stabilization of a premixed hydrogen flame.

Publications
The project plans to publish the results in scientific journals and present them at relevant professional conferences (International Combustion Symposium) and industry meetings (ASME TurboEXPO).