Minimization of life cycle CO2 emissions in the operation of a steam and power plant

A methodology is presented to minimize the life cycle CO2 emissions through the selection of the operating conditions of a steam and power generation plant. The battery limits of the utility sector are extended to include the CO2 emissions of the imported electricity generated by nuclear, hydroelectric and thermoelectric plants. In the life cycle context the CO2 emissions are estimated in the following stages: (i) exploration, extraction and transport of natural gas, oil, coal and uranium consumed in utility, thermoelectric and nuclear plants; (ii) submerged biomass decay in hydroelectric plants and (iii) transport in the construction stage of hydroelectric and nuclear plants. A Mixed Integer Nonlinear programming problem is formulated to select the operating conditions of the utility sector of an ethylene plant in GAMS. Significant reductions in the life cycle CO2 emissions, imported electricity, natural gas consumption and operating cost are achieved and reported in the numerical results.