FlueFlex : Enabling part-load operation of CHP plants with gas turbine exhaust gas recirculation
Even if gas turbines are in general capable to run at part load of 50% - 70% of full load, most CHP units are only used at base load as it is much more difficult to cope with the requirements from the flex power market in combination with the requirement for a reliable heat supply (especially when delivering steam). The challenge for large utility power plants is thus to decrease the minimum load level and to increase the part load efficiency, while staying emission compliant. A solution to this dilemma is the use of Exhaust Gas Recirculation for which flue gas from the chimney are recirculated at the gas turbine inlet.
The research aims at expanding the use of exhaust gas recirculation as it would allow to reduce power generation while still providing reliable heat. To achieve this, the research focuses on EGR cycles through 1) the study of thermodynamic and operating effects on gas turbine components, and 2) the experimental study of combustion stability and emissions in reduced oxygen level combustion. The control strategies developed in the research and a techno-economic analysis will be applied to CHP installations with the help of industrial partners.