Optimal usage of coal, gas and oil in a power plant

Abstract

This study addresses the problem of an optimal actuator selection when economic value is considered. The objective is to minimise the economical cost of operating a given plant. The problem has been formulated using mathematic notions from economics. Functionals describing the business objectives of operating a power plant has been established. The selection of actuator configuration has been limited to the fuel system which in the considered plant consists of three different fuels -coal, gas and oil. The changes over 24 h of operation is established and a strategy for using a plant utilising the three fuels is developed which will yield a greater profit than a coal fired plant.

Profit Maximization of a Power Plant

“…Therefore, some heuristics are introduced to avoid the reference deviations (and non-optimal behavior). From the discrete optimization, it is observed that only one fuel is used at the time, which has also been suggested by earlier work [10], [13]. As a consequence, σ i,j (t) < 0 at any given time, where the notation x i,j means coordinates i and j of the vector x.…”

“…The functions in (4) are in this work assumed sufficiently smooth (C and explanation of the above quantities can be found in [14], [12], [13], and [10]. A prognosis of the next days's electricity consumption is established by Energinet.dk 4 , which is responsible for the electrical grid in Denmark.…”

“…The production plan used in this work is an approximation of a production plan delivered by DONG Energy. These are depicted in Figure 2 (for more details on the production plan see [13]). The plant should follow the generated production plan such that power balance can be upheld.…”

“…If case 2 use λ(t) and E(t) to compute C i (t), i = z, u, t given by (28). Then compute u * (t) using (13). We remark that due to numerical imprecision, in simulations, we have placed a band around 0 of width 1 in which all elements are set to zero.…”

“…The problem stated above has been discussed in [14], [12], [13], and [10]. In particular, the formulation in [10] which includes plant dynamics gives the basis of this work.…”