Pii: S0196-8904(96)00235-x

-Starting with information from Indian Point 1, a full size nuclear plant with fossil-fuel superheat which was built and operated, this paper examines the effect of superheat on both energy and exergy performance, as well as on the thermoeconomics of such plants. The study finds that adding superheat to the nearly saturated steam generated by water-cooled nuclear reactors increases the amount of power generated by at least 70%, the plant efficiency by at least 16%, the plant effectiveness by at least 6%, and reduces the cost of generated electricity by at least 32%. These costs are competitive with fossil-fuel plant generated electricity. These features make fossil-fuel superheat of nuclear power plants interesting both for new plants and for retrofit of existing nuclear plants. Hardware failures which were experienced during the operation of the Indian Point 1 plant appear to be easily avoidable. The superheater accounts for the major portion of exergy destruction in the system excluding the reactor, with the extraction turbine taking second place, and it appears that optimization of their combination will lead to even better system performance. © 1997 Elsevier Science Ltd. Exergy Second law analysis Thermodynamics Advanced nuclear reactors Hybrid power cycles Nuclear power Energy conversion Cf C = Co= Cnf Cu hi ~H = i = m i ~N ~ = m r = p i Q= S~ 1;,= W = Y = G r e e k le t ters AHj= q = £ = NOMENCLATURE Specific exergy at state point i, a~ = (h~ ho) To(s~ So) (kJ/kg) Exergy at state point i, A~ = m~a~ (k J) Cost of electricity (S/kWh) Cost of fossil-fuel (S/G J) Number of atoms of carbon in the fuel Initial capital cost of the plant ($) Non-fuel costs of the plant (capital + O&M) over its lifetime ($) Cost of the nuclear fuel over the plant lifetime ($) Enthalpy at state point i (kJ/kg) Number of atoms of hydrogen in the fuel Interest rate on capital (%) Mass flow rate at state point i (kg/h) Lifetime of the plant (years) Amount of electricity produced over the plant lifetime (kWh) Amount of fuel used over the plant lifetime (G J) Pressure at state point i (MPa) Heat (k J) Entropy at state point i (kJ/(kg K)) Temperature at state point i (°C) Work (k J) Annual operation and maintenance cost (S/year) The lower heating value of fuel (kJ/kg) Energy efficiency Effectiveness (exergetic efficiency)