Abstract: A hybrid power generation system which includes a nuclear facility comprising a nuclear reactor and an exclusion zone. A thermal energy storage, a nuclear steam supply system located, and a solar energy collection system are all located within the exclusion zone. The thermal energy storage vessel contains a thermal mass composition operable to store thermal energy. The nuclear steam supply system has a nuclear reactor and a working fluid loop. The working fluid loop is configured to circulate a working fluid from a steam generator through the thermal energy storage vessel to absorb thermal energy and heat the working fluid for introduction to an electricity generating system. The solar energy collection system includes a heat transfer loop heated via a solar collector. The heat transfer loop is configured to circulate a heated heat transfer fluid to add thermal energy to the thermal mass composition in the thermal energy storage vessel.

Abstract: A solar power generation system having a thermal energy storage system, a solar energy collection system, a power generation system, and an electric generator. The thermal energy storage system has a thermal energy storage vessel containing a thermal mass composition operable to store thermal energy and a plurality of heat exchanger modules. The solar energy collection system has a plurality of heliostats, a tower, and a first closed flow loop including a solar collector with at least one thermal receiver mounted on the tower. The first closed flow loop is configured to transfer the thermal energy to the thermal mass composition in the thermal energy storage vessel from the solar energy collection system. The power generation system has a second closed flow loop including a turbine and configured to transfer thermal energy form the thermal energy storage vessel to the turbine to produce electricity.

Abstract: A system for producing electricity having a primary coolant loop having, in operable and fluid coupling, a vertical nuclear reactor, a vertical once-through steam generator, at least one external hot leg conduit, and at least one external hot leg conduit. The at least one external hot leg conduit fluidly is coupled with the vertical nuclear reactor and to the vertical once-through steam generator to deliver a primary coolant from the vertical nuclear reactor to the vertical once-through steam generator. The at least one external cold leg conduit is fluidly coupled with the vertical nuclear reactor to the vertical once-through steam generator to return the primary coolant from the vertical once-through steam generator back to the vertical nuclear reactor. At least one booster pump is operably coupled to the primary coolant loop to force flow of the primary coolant through the primary coolant loop during normal operation of the system.

Abstract: A method of forming a concentrated solar power system for generating electricity. The method has three steps. The first step is coupling a plurality of tower segments together onsite at a solar energy concentration field to form a solar tower in a lowered orientation. At least one solar receiver is coupled to the solar tower to form a solar tower assembly. The second step is raising the solar tower assembly to a solar energy collection orientation by pivoting the solar tower assembly about a pivot axis located at a bottom portion of the solar tower. The third step is securing the solar tower assembly in the solar energy collection orientation.

Abstract: A solar energy system with thermal energy storage comprises a vessel defining an internal cavity including a partition structure forming multiple vertical heat transfer cells. Each cell is formed by vertical cell walls of the partition structure. Each heat transfer cell contains a separate inventory of a thermal mass composition operable to store thermal energy. A heat exchanger disposed in each cell comprises first and second tube bundles embedded in the thermal mass composition. The first bundle circulates heat transfer fluid heated by solar energy to heat the composition. The second bundle circulates working fluid such as water converted to steam by absorbing heat from the composition for generating power or other steam applications. The cells may be formed by discrete self-supporting transportable tubular modules each supporting one of the heat exchangers. Each cell and heat exchanger therein are independently operably of the others.

Abstract: A nuclear fuel decay heat utilization system usable for space heating in one embodiment comprises a nuclear generation plant building housing a spent fuel pool containing submerged fuel assemblies which emit decay heat that heats the pool. Plural fluidly isolated but thermally coupled heat removal systems comprising pumped flow loops operate in tandem to absorb thermal energy from the heated pool water, and transfer the thermal energy through the systems in a cascading manner form one to the next to a final external heat sink outside the plant building from which the heat is rejected to the ambient environment. A programmable controller operably regulates the intake and flowrate of water from the heat sink into the heat removal systems and monitors ambient air temperature inside to building. The flowrate is regulated to maintain a preprogrammed building setpoint air temperature by increasing fuel pool water temperature to a maximum permissible limit.

Abstract: An automated welding system for sealing high level radioactive waste containers in the field at the nuclear plant site. The system includes a programmable portable robotic welder comprising a multi-jointed articulating robotic arm. A welding head operable to form a weld is mounted to the arm. Operation of the robotic welder and ancillary components is controlled by a programmable controller which implements a welding plan. In one embodiment, a circumferentially-extending lid-to-shell hermetic seal weld may be formed by the robotic welder. The weld is completed in multiple welding passes through the weld joint between the lid and shell guided by an automated joint tracking sensor linked to the controller. The highly portable robotic welder is detachably mountable on the lid to perform the welding. An automated pivotable cable-conduit management apparatus keeps electrically conductive wiring and flow tubing out of the path of the rotating robotic arm during welding.

Abstract: A vertical bundle air-cooled heat exchanger, a finned tube assembly for an air cooled condenser and method for forming the same, and a system for removing thermal energy generated by radioactive materials. In one aspect, an air cooled condenser sized for industrial and commercial application includes an inlet steam distribution header for conveying steam, a condensate outlet header for conveying condensate, an array of tube bundles each having a plurality of finned tube assemblies having a bare steel tube with an exposed outer surface and a set of aluminum fins brazed directly onto the tube by a brazing filler metal. The steel tubes may be spaced apart by the aluminum fins and have an inlet end fluidly coupled to the inlet steam distribution header and an outlet end fluidly coupled to the outlet header. A forced draft fan may be arranged to blow air through the tube bundles.

Abstract: A passively cooled stackable nuclear waste storage system may include a pair of vertically stacked radiation-shielded nuclear waste storage casks. Each cask has a cavity which holds a nuclear waste canister containing spent nuclear fuel or other high-level radioactive wastes. The lower cask may be founded on an above-grade concrete pad. The upper cask is vertically stacked on and detachably coupled to the lower cask. The upper cask comprises a perforated baseplate which establishes fluid communication between cavities of both casks and is configured to prevent radiation shine. One or both casks may include air inlet vents configured to draw ambient ventilation air into each respective cask cavity for cooling the nuclear waste. In operation, air is drawn inward into each cask cavity independently. Air heated in the lower cask rises into the upper cask where it mixes with air drawn into the upper cask and is returned to atmosphere.

Abstract: A natural passively cooled ventilated cask includes a cavity which holds a canister containing heat and radiation emitting spent nuclear fuel assemblies. Cooling air inlet ducts draw ambient cooling air inwards into a lower portion of the cavity. The air heated by the canister flows upwards along the canister and is discharged from at least one air outlet duct formed by the cask lid to atmosphere via natural convective thermo-siphon flow. The air inlet ducts or at least one outlet duct in one embodiment may be fitted with an adjustable shutter plate which allows the flowrate of air entering the cask to be increased or decreased to maintain a predetermined canister maximum temperature limit selected in part to prevent the onset of stress corrosion cracking of the canister welds. Other embodiments may use a fixed orifice plate replaceable over time to maintain the minimum temperature.

Abstract: A power generation system and related method for repowering a fossil-fueled power plant using a carbon-free nuclear steam supply system (NSSS) which replaces the existing fossil plant steam generator which burns fossil fuel such as coal, oil, or natural gas. The existing fossil plant energy conversion system including the turbine-generator (turbogenerator) and auxiliary components of the Rankine cycle is retained. The NSSS may include a small modular reactor (SMR) unit comprising a reactor vessel with nuclear fuel core and steam generator which receives heated primary coolant from the reactor to produce main steam to operate the Rankine cycle. The main steam output by the SMR unit is compressed in a steam compressor to increase its pressure to a level necessary to operate the turbogenerator. The compressor may be operated via a portion of the main steam. An intercooler of the compressor may be used for main steam reheating.

Abstract: A hybrid solar energy power generation system includes a thermal energy storage (TES) vessel containing a thermal mass composition operable to store thermal energy, a concentrated solar power (CSP) system, and a photovoltaic (PV) power system. The CSP system heats a first working fluid flowing in first closed flow loop via a solar collector. The heated first working fluid recirculates through the TES vessel to heat the TM composition. The PV power system generates electricity which can be delivered directly to the electric power grid or alternatively when grid demand drops energizes can electric heaters to supplement heating the first working fluid. This increases the temperature and enthalpy of the first working fluid to store additional thermal energy in the TM composition. The TES vessel is operable to heat a second working fluid to produce steam usable for industrial processes, district heating, or to power a Rankine power generation cycle.

Abstract: A hybrid power generation system in one embodiment comprises a green boiler containing a thermal mass composition operable to store thermal energy, a solar energy collection system which absorbs solar energy to heat a first working fluid and in turn the thermal mass composition, and a power generation system comprising a steam turbine coupled to an electric generator to produce electricity and a nuclear steam supply system which convert a second working fluid comprising water from liquid to steam. Steam output by the nuclear steam supply system flows through the green boiler and is heated by absorbing heat from the thermal mass composition to increase the enthalpy of the steam and concomitantly electric power output from the turbine-generator. The nuclear steam supply system and green boiler may be retrofit to replace existing fossil fuel steam generation systems while retaining the energy conversion part of the fossil power plant.

Abstract: An automatically adjusting seismic restraint system for nuclear fuel storage in one embodiment comprises a free-standing first fuel storage component (FSC) configured to contain nuclear fuel, and a stationary second FSC configured to receive the first fuel storage component. An inter-body gap formed between the FSCs includes at least one seismic restraint assembly. The assembly includes a stationary wedge member fixedly coupled to the second FSC and a movable loose wedge member engaged with and supported in place by the stationary wedge member. The stationary wedge member defines an inclined load bearing surface slideably engaged with a mating inclined load bearing surface of the loose wedge member. During a seismic event or thermal expansion of the first FSC, the first FSC moves towards the second FSC which shrinks the inter-body gap and the loose wedge member is vertically displaced relative to the stationary wedge member while maintaining engagement therewith.

Abstract: A passively cooled stackable nuclear waste storage system includes an at least partially below grade cavity enclosure container (CEC) and above grade cask. Each vessel includes a cavity holding a nuclear waste canister containing spent nuclear fuel or other high-level radioactive wastes. The CEC is founded on a below grade concrete base pad and cask is mounted on an above-grade concrete top pad in a vertically stacked arrangement. The upper cask comprises a perforated baseplate which establishes fluid communication between cavities of both casks and is configured to prevent radiation shine. One or both vessels include air inlets which draw ambient cooling air into their respective cavities for cooling the nuclear waste. Air heated in the lower CEC rises into the upper cask through the baseplate where it mixes with air drawn into the cask and is returned to atmosphere. The system increases storage capacity of new or existing facilities.

Abstract: A radioactive nuclear waste storage system includes a cask comprising a hermetically sealed internal cavity configured for holding the waste such as spent nuclear fuel submerged in an inventory of water. One or more pressure surge capacitors disposed inside the cask include a vacuum cavity evacuated to sub-atmospheric conditions prior to storage of fuel in the cask. At least one rupture disk seals a vacuum chamber inside each capacitor. Each rupture disk is designed and constructed to burst at a predetermined burst pressure level occurring inside the cask external to the capacitor. This allows excess cask pressure occurring during a high pressure excursion resulting from abnormal operating conditions to bleed into capacitor, thereby returning the pressure inside the cask to acceptable levels. In one embodiment, the capacitors are located in peripheral regions of the cask cavity adjacent to the circumferential wall of the cask body.

Abstract: A green boiler includes a thermal energy storage vessel containing a captive bed of a thermal mass composition operable to store thermal energy, an array of heaters embedded in the mass, and at least one heat exchanger comprising a tube bundle. The heaters in one embodiment may be electric and coupled to an electric power source to heat the thermal mass. The tube bundle comprises tubes embedded in the thermal mass composition which are configured to convey heat transfer fluid (e.g., water or other) through a tube-side of the tubes. In operation, the heat transfer fluid is heated by absorbing stored thermal energy from the thermal mass composition. The thermal mass composition may be heated by power extracted from the power grid during off-peak demand periods in some embodiments. The vessel may produce heated water or steam for district heating, or steam for power generation or industrial uses.

Abstract: A system for transporting radioactive materials which may include a containment vessel, a thermal shield, and an impact limiter. The containment vessel may include a vessel body having a storage cavity for receiving radioactive materials, a lid coupled to an upper portion of the vessel body to enclose a top end of the storage cavity, and a lid seal such as a gasket positioned between the lid and the upper portion of the vessel body. The thermal shield may be positioned over the lid. The first impact limiter may be positioned over the thermal shield. The thermal shield may be resistant to high temperatures and may help to protect the integrity of the lid seal when the system is subjected to high temperatures, such as during a fire condition.

Abstract: A containment enclosure for shielding an outer cask containing an inner canister loaded with nuclear waste such as spent fuel rods. The enclosure includes a lower base portion at least partially embedded in a concrete pad and an upper radiation shielding portion defined by a shield jacket coupled to and supported by the lower base portion at a circumferential joint. Cavities of the base and shielding portions collectively define a contiguous containment space for the cask. A portion of the cask resides in each of the base and shielding portions which completely enclose and shield the cask to minimize radiation dosage of personnel in the environment surrounding the cask. The cask is cooled by a natural convectively-driven ambient cooling air ventilation system including air inlets at the circumferential joint of the enclosure. The concrete pad may be part of a spent nuclear fuel storage installation comprising plural cask containment enclosures.

Abstract: A nuclear fuel storage system comprises a fuel rack immersible in a fuel pool which comprises a baseplate and a cellular body extending from the baseplate. The body comprises plural cell walls arranged to define an array of upwardly open cells each configured to store a nuclear fuel assembly therein. A raised fuel assembly support ring may be disposed at the bottom of each cell on the baseplate to engage and support a fuel assembly. A neutron absorber insert disposed in at least one cell comprises a bottom end configured to frictionally engage the support ring to secure the neutron absorber insert therein. The absorber insert comprises resiliently deformable radial locking protrusions which frictionally engage an outward facing annular side surface of the support ring in one embodiment. The absorber insert may be retrofit into existing racks to restore reactivity control.