Retrofit of a 100 kW Micro Gas Turbine for the Use of Hydrogen and Mixtures of Hydrogen and Natural Gas

Abstract This study presents a detailed account of the retrofitting process for the Ansaldo Green Tech micro gas turbine AE-T100. First, the state of the art for gas turbine systems is shown and the necessary steps for a retrofit process are pointed out. For the upgrade on hydrogen the components have to be reviewed and new components have to be chosen. At the same time the official regulations have to be considered for the whole process. Out of this the concepts are derived. The plant layout for the demonstration is introduced. For the hydrogen supply and the admixture of natural gas a blending device was developed and a communication with the MGT was established. One core component for the upgrade on hydrogen operation is the combustor. A new combustor was developed based on the jet stabilized combustion concept and two prototypes were manufactured. Furthermore, the modifications to the MGT are explained. An additional instrumentation package was installed in the MGT, comprising thermocouples and pressure transducers. The internal measurement data was recorded and the emissions were quantified using a Horiba gas analyzer system for CO, CO2, NOx and O2. A measurement campaign was conducted to investigate the two prototypes, including an analysis of the operation with pure hydrogen in transient as well as in steady state conditions. Additionally, the admixture of natural gas was investigated with a focus on emissions and the stability of the combustion process. Successful operation utilizing hydrogen as well as admixtures with natural gas was demonstrated. Corrected NOx emissions below 15 ppm could be achieved with the latest stage combustor prototype operated with pure hydrogen.