This project aims to build upon past research to understand better and address the emissions impact of blending H2 into Capstone microturbines. Prior research indicated that 20% blend levels could be achieved in the C-65 and C-200 models without any observed flashback. However, NOx increases were observed, and controllable up to a limitup to a limit via system settings. Beyond 20% blending has demonstrated the need for additional system modifications to control emissions. The team was able to correlate mixing performance with NOx emissions, showing why NOx levels with 100% H2 testing and H2 injectors may have been elevated compared to NG injectors. The findings suggest minor retrofits can be made on fielded engines via injector modifications to improve mixing.