An analysis of the investment risk related to the integration of a supercritical coal-fired combined heat and power plant with an absorption installation for CO2 separation

For two variants of a supercritical coal-fired combined heat and power plant a thermodynamic, economic and risk analyses were carried out. The first variant consists of a unit working without realization of CO2 capture process. The second one is the unit integrated with a chemical absorption CO2 capture installation. In this variant the heat required for the desorption process is supplied with steam extracted from the steam turbine. The developed model of the CHP plant allowed to obtain main operation characteristics for annual change of load. For the two analyzed variants the characteristics of the amount of produced electricity (gross and net), generated heat and consumed chemical energy of fuel, as a function of the cogeneration unit operation time per year, were determined. In the next stage of calculations these characteristics were required to carry out the economic and risk analysis. Economic performances were evaluated in terms of the break-even price of electricity. The performed analysis proves that both investment projects will achieve the same economic effect, i.e. 85.26 €/MW h, if the price of emissions allowances reaches the value of 47.88 €/MgCO2. In this case, the potentially better variant of the system may be indicated based on the result of the risk analysis. In order to perform the risk analysis the main technical and economic risk factors concerning implementation of this technology were identified. The risk analysis was conducted with the use of Monte Carlo method. Based on the determined cumulative probability curves of obtaining specified values of the break-even price of electricity, it was possible to obtain values for defined in the paper indices of the investment risk assessment. The results of risk analysis are presented and discussed in the paper.