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From uncertainty to vitality: The future of nuclear energy in Illinois
Nuclear is enjoying a bit of a resurgence. The momentum for reliable energy to support economic development around the country—specifically data centers and AI—remains strong, and strongly in favor of nuclear. And as feature coverage on the states in the January 2026 issue of Nuclear News made abundantly clear, many states now see nuclear as necessary to support rising electricity demand while maintaining a reliable grid and reaching decarbonization goals.
Gilberto Espinosa-Paredes, Jose Alvarez-Ramirez, Alejandro Nuñez-Carrera, Alfonso Garcia-Gutierrez, Elizabeth Jeannette Martinez-Mendez
Nuclear Technology | Volume 145 | Number 2 | February 2004 | Pages 150-162
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT04-A3466
Articles are hosted by Taylor and Francis Online.
A comparative analysis of the dynamic behavior of a boiling water reactor in a full-scope power plant simulator for operator training is presented. Three- and four-equation reactor core models were used to examine three transients following tests described in acceptance test procedures: scram, loss of feedwater flow, and closure of main isolation valves. The three-equation model consists of water and steam mixture momentum, including mass and energy balances. The four-equation model is based on liquid and gas phase mass balances, together with a drift-flux approach for the analysis of phase separation. Analysis of the models showed that the scram transient was slightly different for three- and four-equation models. The drift-flux effects can explain such differences. Regarding the loss-of-feedwater transient, the predicted steam flow after scram is larger for the three-equation model. Finally, for the transient related to the closure of main steam isolation valves, the three-equation model provides slightly different results for the pressure change, which affects reactor level behavior.