| Type | Private |
|---|---|
| Industry | Nuclear power |
| Founded | Santa Fe, New Mexico, USA |
| Headquarters | Santa Fe, New Mexico |
| Key people | Robert E. Prince, CEO Otis G. Peterson, Chief Scientist |
| Website | www.hyperionpowergeneration.com |
Hyperion Power Generation, Inc. is a privately held corporation formed to construct and sell several designs of relatively small (70 MW thermal, 25 MW electric) nuclear reactors, which they claim will be modular, inexpensive, inherently safe, and proliferation-resistant. According to news coverage, these reactors could be used for heat generation, production of electricity, and other purposes, including desalinization.
The company is currently attempting to license their technologies through the U.S. Nuclear Regulatory Commission.
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Hyperion announced in November 2009 that, despite their continued intentions to pursue the self-moderated uranium hydride reactor, urgent customer needs for a rapidly licenseable and deployable reactor are causing them to choose another LANL design for initial commercialization. They are moving forward with a more conventional Generation IV reactor design: a uranium nitride fueled, lead-bismuth cooled reactor. Using a liquid-metal-cooled fast reactor should speed the time to commercialization over the more revolutionary uranium hydride, self-modulating design that had previously been publicly discussed.[1]
According to Hyperion, the uranium nitride fuel incorporated in the design is generally similar in physical characteristics and neutronics to the standard ceramic uranium oxide fuel that is used at present in modern light water nuclear reactors. However, it has certain beneficial traits - higher thermal conductivity - and thus less retained heat energy - that make it preferable over oxide fuels when used at temperature regimes that are greater than the 250 to 300 °C (482 to 572 °F) temperatures found in light water reactors.[3] By operating at higher temperatures, steam plants can operate at a higher thermal efficiency. The presentation by Hyperion at the ANS 2009 conference mentions the use of the Doppler inherent negative temperature coefficient of reactivity in this reactor as a means of control.[4] Nuclear scientist Alexander Sesonske avers that nitride fuels have both received very little development (as of 1973) and seem to have a very favorable combination of physical properties - especially in fast reactors.[5] Whether this carries over to lead-bismuth cooled reactors is a question not answered in the reviewed literature, though the Soviet Union has worked with this type of reactor before in naval service; in particular, the Alfa class submarine - well known in the West for its high speed operation - was driven by such a lead-bismuth reactor which is known to have worked very effectively.[3]
The Hyperion module has sufficient fuel for 3650 full power days at 70 MWth, is capable of load following, and is meant to be built in pairs; one module can be at power, while another can be under installation or uninstallation at the same time, ensuring reliable supply of electricity.[3]
Hyperion plans to use natural circulation of the lead-bismuth coolant through the reactor module as a means of primary cooling. Coolant temperatures within the primary loop should be approximately 500 °C (932 °F). Powered intermediate heat exchangers, also using lead-bismuth coolant, are located within the reactor and run an intermediate loop going to a third ex-reactor heat exchanger (the steam generator), where heat is transferred to the working fluid, heating it to approximately 480 °C (896 °F). Two schemes of power generation exist at this point: either using superheated steam or supercritical carbon dioxide to drive Rankine cycle or Brayton cycle turbines. In addition to the classical use of power generation, further uses for the heated working fluid can include desalinization, process heat, and district heating and cooling.[3]
The thermal hydraulics of the lead-bismuth reactor are dictated by the high heat capacity and unique properties of the lead-bismuth eutectic coolant. This coolant has several extremely beneficial properties for a reactor: it is opaque to gamma radiation, but transparent to neutron flux; it melts easily at a low temperature, but does not boil until an extremely high temperature is reached; it does not greatly expand or contract when exposed to heat or cold; it has a high heat capacity; it will naturally circulate through the reactor core without pumps being required - whether during normal operation or as a means of residual decay heat removal; and it will solidify once decay heat from a used reactor has dropped to a low level.[3]
Four mechanisms of control are used in the reactor. There are two types of control rods - rapid shutdown rods, designed to promptly absorb a large quantity of reactivity from the reactor to bring it below the shutdown margin, and fine-grained working control rods, also known as shims, which are used to compensate for the long-term decrease in reactivity (long-term decrease in Keff) that comes from the nuclear fuel being depleted and fission products being formed. The shims, in particular, have 1.5 metres (4.9 ft) of travel distance which they slowly travel over the life of the reactor. There is a secondary shutdown system consisting of neutron-absorbing boron carbide balls that can be launched into the core in the event the shutdown rods are not responsive and rapid shutdown is called for. Fourth, there is the prompt negative temperature coefficient of reactivity, which prevents the reactor from remaining critical if it should enter into an unsafe temperature range. The reactor is designed so that once shut down, it does not require external agencies aside from natural conduction and convection to surrounding natural media to remove residual heat, qualifying it as highly safe.[3]
The reactor weighs 20 tonnes (44,000 lb) fully fueled (including coolant), and it can be transported by truck or by rail to its destination. Radiation protection during transport is integral, making it nearly impossible for any transport accident to threaten the release of radiation. As the coolant is composed of lead (a strong absorber of gamma radiation), the reactor is very safe for humans to be in close proximity to while the reactor is transported; further, if the reactor is allowed sufficient time to eliminate decay heat prior to transport, the lead-bismuth coolant will be in solid phase, thus fixing the internals of the reactor in place, causing the reactor to behave as a single piece of metal if subjected to external shock.[3]
Hyperion intends to pursue the licensing of the uranium nitride, lead-bismuth small reactor with the U.S. Nuclear Regulatory Commission (NRC), though the firm's deployment schedule - the target date for deployment will be by the end of 2013 - as well as indications from senior personnel within Hyperion indicates that perhaps the reactor will bypass the normal NRC process for commercial reactors - as it takes many years - and will instead be initially deployed by the U.S. Department of Energy or the U.S. Department of Defense, not subject to NRC regulation, or that Hyperion will seek a 10CFR50.21 Class 104 Research and Development reactor license from the NRC.[3] As of May 2010[update] Hyperion expects to apply to the NRC for regulatory approval "within a year."[6]
Possibilities for manufacture in nations other than the United States have also been mentioned as a way to overcome the NRC's lesser agility in responding to the commercial introduction of unique and innovative features of this reactor design. In particular, Hyperion plans to manufacture reactors in the United Kingdom, which has demonstrated recent national leadership in the field of nuclear energy, while a yet to be announced nation in Asia is targeted for manufacture as well.[3]
As of November 2009[update], no uranium nitride fuel for the design has been tested or manufactured for the project, but Hyperion claims that fuel burns will begin before year-end 2009.[1]
As of September 2010[update], the company announced an agreement with Savannah River Nuclear Solutions, operator of the Savannah River National Laboratory in Aiken, South Carolina, for the development of a demonstration site, intended for testing and licensing purposes, at Savannah River.[7] [8]
In 2008 and 2009, Hyperion planned to initially commercialize a small, modular self-regulating, uranium hydride reactor,[9] based on a design by Dr. Otis G. Peterson, formerly of Los Alamos National Laboratory, (with United States patent application #11/804,450) for a unique modular nuclear reactor design that Peterson developed while working for LANL.[10] [11] According to the U.S. Nuclear Regulatory Commission, Dr. Peterson has licensed the pending patent to Hyperion Power Generation, Inc.[12]
In November 2008, the Nuclear Regulatory Commission (NRC) indicated that investigation of the design is not expected to begin until February 2009 and that they expect "that it will take significant time to ensure safety requirements."[13]
As of September 2009[update], Hyperion expected to sell 4,000 units of the "2008-design" version of its Hyperion Power Module, at an estimated US$25–30 million each, and expected to ship its first unit in June 2013,[14] before the company moved on to a second-design in 2009.[15] In early 2009, the company had more than 100 orders for the "2008-design", with plans to build manufacturing facilities in the United States, the United Kingdom, and Asia.[16]
See List of small nuclear reactor designs