HOLTEC INTERNATIONAL

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.

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.

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.

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.

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.

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.

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.

A solar power generation system includes a thermal energy storage vessel containing a thermal mass composition operable to store thermal energy, solar energy collection system, and power generation system. The collection system comprises a first closed flow loop including a solar collector which absorbs solar energy and heats a first working fluid. The heated first working fluid recirculates through a first closed flow loop through and heats the thermal mass composition. The generation system comprises a second closed flow loop including a turbine-generator. The second closed flow loop recirculates a second working fluid through the thermal mass composition to absorb thermal energy and heat the second working fluid which flows to the turbine and the generator produces electricity. The second working fluid may be water/steam or a compressible gas. The thermal mass composition comprises a mixture of a phase change material such as salt and a metallic material.

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.

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.