The following data is provided for a combined cycle cogeneration plant installed in the chemical industry: Steam production: 42 t/h of saturated steam at 15 bar; Electrical energy production: 210,000 MWh/year; Natural gas consumption: 550,000 MWh/year; Annual operating hours: 8,100. For the above cogeneration system, draw at least two possible operating diagrams, detailing the main characteristics of the selected heat engine. a) The annual useful heat provided by the cogeneration system b) The thermal, electrical, and overall performance of the cogeneration system c) The heat-to-electricity ratio, RCE, of the cogeneration system. d) The equivalent electrical performance, REE, of the cogeneration system. e) Primary energy savings in toe/year for standard performance values of electricity and heat generation of 35% and 85 %, respectively.