The use of renewable energy sources raises the demand of fast and flexible storage techniques and fast power availability to ensure electrical grid stability. A promising storage approach is the production of hydrogen and oxygen by electrolysis. The possibility of using a completely closed cycle of water, hydrogen and oxygen promises an attractive approach for high efficiency, zero emission energy storage. Since electrolysis can be carried out under high pressure, the compressor part of the gas turbine would be unnecessary, which is beneficial in terms of efficiency. Furthermore, high turbine pressure ratios, compared to typical gas turbine applications, can be reached easily.
However, the combustion of hydrogen and oxygen in gas turbines is a challenging task. Hydrogen and oxygen mixtures are extremely reactive and result in very high flame temperatures. In the present study the feasibility of steam-diluted combustion of hydrogen and oxygen at stoichiometric conditions is shown. A suitable combustor is developed and experimentally validated. The degree of humidity is varied systematically for stoichiometric hydrogen oxygen combustion. Flame shapes, temperature estimations and operating limits are compared and discussed.