Mathematical description of combined cycle gas turbine power plants' transient modes

Combined heat and power plants running conditions refer to the frequent start-ups and shut-downs with and without warm state preservation due to the nature of intermittent generation and electricity market mechanisms implementation. Recently the number of transient modes (shutdown, start-up, warm state preservation) were increasing dramatically. They were costly and unfavorable from technical, economic and environmental point of view. Now the transient modes cannot be omitted in the cost benefit analysis and optimization models of power plants as it was admissible previously, when they were operated at based load. In this publication the mathematical description of the transient modes is provided and mathematical models are developed for the calculations of the duration, produced energy amount and variable costs (fuel and CO
₂
emissions) of the transient modes.