Market Basis for Salt-Cooled Reactors: Dispatchable Heat, Hydrogen, and Electricity with Assured Peak Power Capacity

Abstract

Energy markets are changing because of (1) the addition of nondispatchable wind and solar electric generating capacity and (2) the goal of a low-carbon energy system. The large-scale addition of wind and solar photovoltaics results in low wholesale electricity prices at times of high wind and solar output and high prices at times of low wind and solar input. The goal of a low-carbon energy system requires a replacement energy production system with assured peak energy production capacity. To minimize costs, capital-intensive nuclear reactors should operate at base load. To maximize revenue (minimize sales at times of low prices and maximize sales at times of high prices), the power cycle should provide variable heat and electricity. This requires the power cycle to (1) include heat storage that enables peak heat and electricity output that may be several times base-load reactor output and (2) provide assured peak power production. Assured peak power production requires the capability to efficiently burn lowcarbon fuels such as hydrogen and biofuels. Alternatively, nuclear systems with base-load reactors can be built to produce peak electricity and storable hydrogen for industry, biofuels, and other markets. All power reactors with appropriate system designs can meet these requirements. The lowest-cost technologies for heat storage, assured peak power production, and hydrogen production require high-temperature heat. This economically favors salt-cooled reactors with the average temperature of delivered heat of about 650°C versus heat delivered at lower average temperatures from other reactors such as light water reactors: 280°C, sodium-cooled reactors: 500°C, and high-temperature helium-cooled reactors: 550°C. Salt-cooled reactors include (1) Fluoride-salt-cooled High-temperature Reactors (FHRs) with solid fuel and clean salt, (2) Molten Salt Reactors (MSRs) with fuel dissolved in the salt, and (3) fusion reactors with salt blankets. Future energy markets, nuclear systems (heat storage, assured peak energy production capacity, and hydrogen production) designed for such markets and the power cycle technologies that economically favor salt reactors are described.

Radiation-induced reaction kinetics of Zn2+ with eS− and Cl2˙− in Molten LiCl–KCl eutectic at 400–600 °C

“…Interest in the chemistry of molten salts in radiation environments is in resurgence due to the potential of molten salt reactors (MSRs) to revolutionize the nuclear energy landscape. 1,2 Both fluoride and chloride salt systems have been proposed as reactor coolant and fuel matrix candidates. However, the radiation science underpinning molten salts is in its infancy compared to water radiolysis, which is critically important for managing water-cooled reactor technologies.…”

Molten salts: Potential candidates for thermal energy storage applications

“…The KCl-MgCl 2 salt combination is by far the most preferable in terms of cost and easy availability. 146…”

“…The discharged molten salt also showed the highest temperature (625°C) as compared to the other candidates studied (KCl‐MgCl 2 and KF‐ZrF 2 ). The KCl‐MgCl 2 salt combination is by far the most preferable in terms of cost and easy availability 146 …”

Nuclear Air-Brayton Power Cycles with Thermodynamic Topping Cycles, Assured Peaking Capacity, and Heat Storage for Variable Electricity and Heat

“…Initial studies 19 are underway on a third-generation nitrate salt-crushed rock system for high-temperature nuclear reactors to further lower capital costs to a few dollars per kilowatt hour of heat storage. The tank structure would be replaced by an insulated trench up to 60 m wide and 20 m high and lengths that may exceed 1000 m with no internal structures.…”

“…Work is underway to develop systems with crushed rock in the tanks to replace some of the oil inventory 20 and systems where the crushed rock is in large trenches. 19…”