This contribution elaborates on a futuristic hybrid concept for the multifunctional employment of a liquid air energy storage (LAES) system for combined heat, cold and power production (tri-generation) in a food factory, thereby providing a substantial part of the energy demand for various unit operations and enhancing the round-trip efficiency (RTE) of LAES. A processing line for frozen French fries, with relatively high heating and refrigeration demands, is used as a case study. The total useful energy output per charge/discharge cycle is 61,677 kWh (i.e., 38,295 kWh of electricity, 19,278 kWh of heating, and 4104 kWh of refrigeration). The estimated tri-generation RTE of the studied system reaches 55.63%, which appears to be 1.2 times higher than the RTE of a classical standalone LAES system with the same power input, considered as a baseline. In a broader context, such a performance enhancement by amalgamating food and energy technologies can make cryogenic energy storage a more viable grid balancing option capable of substantially increasing the share of renewables in the energy supply mix.

This paper proposes a combination of a nuclear and a concentrated solar power (CSP) plant. Most of today’s operating nuclear reactor systems are producing saturated steam at relatively low pressure. This, in turn, limits their thermodynamic efficiency. Superheating of nuclear steam with solar thermal energy has the potential to overcome this drawback. An innovative configuration of a hybrid nuclear-CSP plant is assembled and simulated. It brings together a small pressurised water reactor and a parabolic trough solar field. The solar heat is transferred to nuclear steam to raise its temperature. Continuous superheating is provided through molten salts-based thermal energy storage (TES). The results from design point calculations show that solar superheating has the potential to increase nuclear plant electric efficiency significantly. Solar heat to electricity conversion efficiency defined as the ratio of extra generated power to collected solar energy reaches unprecedented rates of 52%. An off-design model was used to simulate 24-h operation for one year by simulating 8760 cases. Due to TES non-stop operation is manageable. Abbreviations: CSP: concentrated solar power; DNI: direct normal irradiation; FR: Fresnel reflectors; HP: high pressure; HTF: heat transfer fluid; NPP: nuclear power plant; PT: parabolic trough; PV: photovoltaic; PWR: pressurised water reactor; RPV: reactor pressure vessel; SANPP: solar-assisted nuclear power plant; SM: solar multiple; SMR: small modular reactor; ST: solar tower; TES: thermal energy storage

This article proposes a combination of nuclear power plant and grid-scale energy storage, classified as Carnot battery. The electric heater heats molten salts when excess electricity is available in the grid. The steam that is produced in a small modular nuclear reactor is heated with hot molten salts in the external super-heater. For continuous superheating to be ensured, the plant is equipped with molten salt thermal energy storage. The combined plant and reference NPP are modelled and simulated at steady-state conditions. Due to the higher turbine inlet temperature, the efficiency of the combined generation-storage nuclear plant is substantially improved. The proposed concept makes the co-location of NPP and Carnot Battery more attractive than the separate plants. The integrated thermal storage acts as secondary electricity storage. As such, it surpasses compressed air storage and is competitive with the pumped hydro storage, in the absence of their geographical and environmental constraints.

One of the most promising approaches for replacing conventional power plants during the transition to clean energy is the conversion of existing coalfired power plants (CPPs) into nuclear power plants. This strategy offers numerous ecological and economic advantages. However, integrating a nuclear reactor with a steam turbine originally designed for a coal plant is far from trivial and involves significant technical challenges. The purpose of this work is to analyze and evaluate various options for coupling a HighTemperature GasCooled Small Modular Reactor (HTGR SMR) with a potentially suitable subcritical steam turbine from an existing CPP, thereby creating several repowering configurations. The main difficulties stem from the fact that the turbine was designed to operate with live steam at lower flow rates, temperatures, and pressures than those typically provided by an HTGR SMR. In addition, the feedwater temperature and pressure requirements for the HTGR SMR steam generator differ substantially from those in a CPP, leading at best to additional efficiency losses. Moreover, the overall thermal cycle layouts of the two systems are fundamentally different. Despite these challenges, technically feasible combinations can be achieved. However, determining which option is the most economically viable depends on numerous additional factors, including the specific characteristics of the individual CPP and the regulatory framework of the country in which it operates.