PSM’s Jeffrey Benoit Details Ammonia Combustor Development at DLR

Alternative fuels were a major discussion topic at POWERGEN International 2026, with several OEMs providing the latest updates on their demonstration testing, project installations, and more across key technical sessions. PSM, a Hanwha company, joined the trend with several sessions regarding its FlameSheet and newly developed ammonia combustor technology, developed as part of its recently announced agreement with Baker Hughes.

Jeffrey Benoit, Vice President of Clean Energy Solutions at PSM, established a comprehensive and technical overview of the company’s ammonia combustor development during his interview with Turbomachinery International. Per Benoit, a primary focus in the development process was controlling the high NO_x emissions produced via ammonia’s long ignition speed and notable flame temperature.

TURBO: What specific combustion challenges does ammonia present compared to natural gas and hydrogen, and how did those challenges shape the combustor architecture?

Benoit: The differences between hydrogen, natural gas, and ammonia are quite stark when you’re combusting them in a gas turbine. Hydrogen is very volatile with a quick ignition speed and propensity to be ignited in areas it shouldn’t be. It’s much harder to use hydrogen in [combustion]. Most of the combustion architecture in modern gas turbines are optimized for natural gas operation.

Ammonia is a non-traditional fuel with a very long ignition speed: The flame is much larger and harder to ignite for combustion in a gas turbine. It also produces a very hot flame, which increases the levels of nitrous oxide (NO_x). This is regulated by the United States’ government, particularly the EPA…We’re employing a Rich-Quench-Lean combustion system. We’re first igniting the fuel, and it will generate a certain amount of NO_x as the flame temperature rises. Then, we immediately quench with cool air to cut off this reaction.

TURBO: What were the most critical lessons learned from fuel injection and mixing schemes during high-pressure testing at DLR?

Benoit: DLR is one of the national laboratories in Germany—this one is based in Cologne. We have over 20 years of experience working with [DLR], looking at and developing our various combustion platforms. Initially, they did not have a system to consume or use ammonia for combustion testing. As Hanwha and PSM, we installed an ammonia vaporization system to enable partial-pressure testing and then full-load, full-pressure testing. That was the first barrier we needed to overcome.

Secondly, our emissions equipment needed to handle a broader NO_x range as we were dialing in the geometry, architecture, and the combustor’s pressure-drop considerations. This allows the appropriate mixing to happen in both the first portion and lean portion of the combustion system. As we pushed the envelope, we expected to over-temperature and likely melt some of our hardware—it is part of the combustion development process. We needed to push the limits and validate our assumptions and models to make sure it operates per design intent.