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NPR TECHNOLOGY ASSESSMENT

ABSTRACT

The Energy Research Advisory Board (ERAB) has reviewed and assessed reactor technologies as candidates for new reactor capacity to produce tritium (and possibly plutonium) to meet U.S. requirements for nuclear weapons materials. In its assessment, the Board emphasized the equal and primary importance of producing goal quantities of tritium when needed and doing so in a safe and environmentally sound manner. Particular strengths and weaknesses of each technology were evaluated in six areas (Technology Base, Safety and Environmental, Schedule, Costs, Industrial Base, and Institutional Acceptance).

The ERAB evaluation has found that Heavy Water Reactor technology is the most mature technology for tritium production at the present time. Each of the technologies considered (others are the High Temperature Gas-Cooled Reactor, the Light Water Reactor, and the Liquid Metal Reactor) could meet the mission requirements for new production capacity with varying degrees of risk as to cost and schedule. Use of multiple reactors to provide the capacity, possibly with diverse technologies and located at different sites, would provide high production assurance, reduce uncertainties in the schedule, and minimize the risk to national security, but at increased cost. Deployment of a single reactor is the lowest cost approach but carries the operational risk of unexpected loss of all capacity for an extended period. The Board found that, with early planning, there is an opportunity to gain revenues to offset costs by the sale of steam at the site boundary for power production.

Safety is a primary consideration in the design, construction, and operation of the new reactor capacity and is of major importance to the technology selection. The Board believes that the design should take full advantage of the results of safety research to date, and that proposed safety goals and a sound safety review process will provide a level of safety that is at least equivalent to that of the best of current commercial power plants. Moreover, the advanced reactors (High Temperature Gas-Cooled Reactor, Liquid Metal Reactor, and such concepts as a small advanced Light Water Reactor) provide an opportunity for a potentially significant advancement in the level of safety over current commercial reactor experience.

EXECUTIVE SUMMARY

The Energy Research Advisory Board (ERAB) has reviewed and assessed the Heavy Water Reactor (HWR), the High Temperature Gas-Cooled Reactor (HTGR), the Light Water Reactor (LWR), and the Liquid Metal Reactor (LMR) as candidates for New Production Reactor (NPR) capacity, as requested by the Secretary of Energy in his letter of January 7, 1988. A subsequent letter of April 28, 1988 requested that duality issues (use of two or more reactors for tritium production), diversity of reactor technologies, and more than one site be included in the assessment.

The ERAB reviewed the Department's proposed selection criteria for use in evaluation of the four candidate NPR technologies. For the most part, the ERAB accepted the criteria as a suitable basis for evaluation of the NPR technology. The six criteria areas are:

O Technology Base

O Safety and Environment

O Schedule

O Costs

O Industrial Base

o Institutional Acceptability

The Board emphasized the equal and primary importance of producing goal quantities of tritium when needed (Technology Base) and doing so in a safe and environmentally sound manner (Safety and Environment). The Board also identified public acceptance as an important part of the institutional acceptability criterion.

The ERAB recognizes the potential national security risks associated with interruptions of the Nation's tritium supply, and the need for the highest possible technical excellence and national confidence in assuring the future supply of tritium. New production capacity can be obtained only with public support, high confidence in public safety, and the availability of excellent technology.

Safety is a primary consideration in the design, construction, and operation of the NPR and is of major importance to the NPR technology selection. The Board believes that the design features of the NPR should take full advantage of the results of reactor safety research to date, and that management procedures should be established with disciplined lines of responsibility, accountability, and authority.

Technical Evaluation

The ERAB reviewed and assessed the candidate technologies according to the foregoing criteria based upon U.S. experience with each technology over the past 35 years and on design concepts presented to the Board for this evaluation. The design concepts and background information presented by proponents of each technology have, generally, been adapted to this application from commercial power reactor studies or from ongoing reactor program activities supported by government or industry. The NPR project has not yet been fully defined and there have not been compatible conceptual designs for an NPR based on the candidate technologies. As such, the design proposals and technology development programs presented to the ERAB have not been consistent as to their state of development, maturity, missions, and characteristics. Therefore, the ERAB has focused on the capabilities and potential of the underlying technologies for the different types of reactors rather than current technology and specific designs.

Particular strengths and weaknesses of each technology are shown in the Table at the end of the Executive Summary. The technical evaluation by the ERAB can be summarized as follows:

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Each of the reactor types considered can meet the mission requirements of a NPR with varying degrees of risk as to cost and schedule.

The Heavy Water Reactor has the most mature U.S. technology for tritium production at the present time. The other reactor types require varying degrees of research, development, and qualification testing of the lithium target technology to make tritium, with the High Temperature Gas-Cooled Reactor target technology being the most advanced. The LWR has the most nature and widely used reactor technology for power production.

o With proper design and a sound safety review process, each of the technologies can provide a NPR with a level of safety that is at least equivalent to that of the best of present commercial power plants. Radiation exposures to people, both on-site and off-site, are expected to be less than current practice. The advanced reactors (High Temperature Gas-Cooled Reactor, Liquid Metal Reactor, and such concepts as a small advanced LWR) provide an opportunity for a potentially significant advancement in the level of safety over current commercial reactor experience.

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