ARIES Documents

Utility Advisory Committee Reports

I. Introduction

The meeting was convened for three purposes: 1. To review a paradigm for the promotion of fusion power plants that had been developed by the Fusion Power Plant Studies Program using input provided by the committee during its first two meetings; 2. to learn of the latest developments within the Fusion Power Plant Studies Program, certain of which had resulted from discussions held during the first two committee meetings; and 3. to up-date the committee on the status of fusion and near term plans for the U.S. program from an industrial perspective presented by Dr. David Overskei, General Atomics. In particular, three major discussions took place during the meeting. These concerned: refinement of the paradigm itself, to better promote fusion by optimizing the perception of fusion's specific advantages; the licensing process for a fusion power plant; and the role of DEMO and the goals that it must meet, as viewed by a utility.

The original paradigm that had been developed by the Fusion Power Plant Studies Program was intended to embody those beneficial elements of fusion that would result in the most persuasive case that a CEO or VP might present to the board of directors of an electric utility when requesting that they invest in fusion power plants. In developing the paradigm, a number of fundamental assumptions had been made. These were reviewed in depth by the committee, emphasis being placed upon refinement of the specific advantages of fusion, and upon methods to promote it. As a result, the original paradigm was developed further and is summarized in section II.

II. The Paradigm

Two paradigm objectives were identified, one based on the case to be made in support of fusion power plants prior to DEMO and one based on the case to be made post DEMO operation. The intention is to distinguish between investing in the early DEMO, where power producers would share the cost of the plant with government onsome negotiated basis, for example 50/50, and investing in subsequent commercial fusion power plants where the total cost would be borne by the power producers.

II.1 Paradigm Objective

a. PRE-DEMO

Provide the elements of the case to be made to the Board of Directors by the CEO or VP that the utility company should participate in a consortium together with other private-sector companies and the U.S. Government to build a Fusion DEMO.

b. POST-DEMO

Provide the elements of the case to be made to the Board of Directors by the CEO or the VP that the utility company should accept a fusion plant as the next electric plant on the system. This plant will be part of an overall mix of power producing and power conditioning units in the system.

II.2 Elements of the Paradigm

Here, we summarize the key statements associated with each element of the case to be presented to the Board of Directors. Colloquially, these are the "arrows in the quiver" of the CEO or VP.

PRE-DEMO ARGUMENT FOR A FUSION PLANT

Element 1.a: Economics

Fusion plants have the potential for cost competitiveness with competitors. The cost estimate for the DEMO is not more than about 20% greater than competitors, and there is a pathway to a commercial system that is up to 20% less expensive than competitors.

POST-DEMO ARGUMENT FOR A FUSION PLANT

Element 1.b: Economics

Fusion plants are cost competitive with other central station options. Indeed, there must be a clear cost advantage (of the order of 10% or more) for fusion power plants.

Element 2: Licensing

Fusion Licensing is Easy and there is No Need for Evacuation Plan.

* Reasons:

* Large cost penalty is associated with (fission) licensing.

* Minimum environmental impact and positive public perception.

* Maximum siting flexibility and be consistent with the size of the distribution grid.

* Consequence:

* Develop fusion-specific regulations.

* Avoid fission regulations.

* Avoid fission lexicon and terminology. Part of conditioning ourselves that fusion is in fact really different.

* Avoid requirement for the Design Basis Accident.

* Utilize low-activation material.

Element 3: Waste Disposal Environmental Impact and Attributes

Fusion Produces No Long-Lived High Level Waste.

* Reason:

* Minimum environmental impact and positive public perception.

* Consequence:

* Utilize low-activation material. - Must keep 10CFR20, but must get rid of much of 10CFR. (May have Class C waste but do not have waste comparable to fission products and actinides.) Do not need Appendix A, B, J, K, R of 10CFR50. - They are irrelevant and do not apply.

Element 4: Reliability and Availability

Fusion Power is Reliable, Available, and Stable as an Electric Power Source.

* Reason:

* Low-operating-cost, high-profit-margin energy source.

* Consequence:

* All the fault conditions expected of the plant result in benign shut-downs with minimal consequences to plant, and the plant re-starts quickly after any such event.

* Power plant unscheduled shut-downs should be kept below 1 shut-down per year. (INPO objective for fission power plants in 1995.) Failure to pulse would be equivalent to an unscheduled shut-down.

Element 5: Atmospheric Environmental Impact and Attributes Argument

Fusion has No Local or Global Atmospheric Impact.

* Reason:

* Minimum environmental impact and positive public perception (no greenhouse and acid-rain gases).

* Insurance against future regulations and constraints in this area.

* This asset might make tax incentives available.

* Consequence:

* Fusion will meet these characteristics.

Element 6: Fuel Availability and Transportation Argument

Fusion Fuel Cycle is Closed on Site, and Fuel Availability is High.

* Reason:

* Utility protected from issues associated with the cost and availability of fuel supply.

* Consequence:

* Plan for no radioactive fuel shipments other than first start-up deliveries.

Element 7: Plant Operating Flexibility Argument

Fusion Plant has the Capability for Load Following.

* Reason:

* Additional arrow, but is not needed to introduce large baseline plants to the market.

* Consequence:

* Demonstrate that fusion plant follow (a desirable range for load following is about 2/1).

Element 8: Range of Power Plant Size and Capacity Argument

Fusion Plants have a Capability for a Range of Unit Size.

* Reason:

* Flexibility in the installed electrical base. We want market "pull", not technology "push".

* Consequence:

* Determine the minimum-size fusion power plant that meets the utility need.

* This has to be balanced against the advantages of a standard design.

III. Discussion of Paradigm Elements

III.1 ON FUSION AS THE PRIMARY FUTURE POWER SOURCE

In earlier meetings, it was assumed as part of the paradigm that fusion plants would be the primary future source of electric power. The consensus now is that a case advocating fusion power plants to a board of directors would advocate that a fusion plant be the next electric plant in the system. A utility is unlikely to confine itself to one technology but will always seek an appropriate mix.

III.2 ON COST COMPETITIVENESS

The topic of cost competitiveness, for which equality with other central station options had been assumed in the paradigm, was debated. The committee pointed out that cost competitiveness was not a sufficient criterion and that a fusion plant would have to offer a real cost advantage to succeed. The consensus was that a cost advantage of the order of 20% would be necessary for a new technology to be accepted. Furthermore, existing electric generating technology was going down in cost and it was anticipated that the costs of plants based upon established technical criteria would experience reductions of about 20% over the next several years. Hence fusion is aiming at a moving target.

However, it was conceded that predictions of conventional plant costs did not take into consideration any environmental penalties that might be imposed upon them in the future. The point was made that the further away a technology was from its implementation, the greater were the uncertainties in the cost of implementation and, hence, the larger the contingencies that were applied to it. For fusion, if the contingencies were stripped away, then an anticipated cost for plant that did not exceed conventional costs by more than 20% might be acceptable, provided that a pathway could be identified along which to progress from a DEMO to a commercial plant that would lead to a 10 - 20% competitive edge.

Since a penalty may be placed upon the future use of conventional fuels, this raised the question: "20% more competitive than what?" This uncertainty not withstanding, the committee stressed that a cost model for a fusion power plant needs to be established from the outset. That model needs to focus on fusion technology and how it is going to reduce costs. Today, there is a spread of potential improvements for existing technologies which could be implemented to reduce the effective cost of power plants by improving their efficiencies. It was pointed out to the committee that the Fusion Plant Studies Program had already made a cost analysis and had compared this with cost projections for advanced light-water reactor (ALWR) facilities. ALWR costs were projected to be 20% below costs of existing technologies; fusion costs could match ALWR costs. Hence, should ALWR plants prove to be environmentally acceptable, should their costs meet projections, and should they establish a sound record of reliability, such facilities will be the future "conventional" plants with which fusion must compete. The conclusion was that it would be very difficult to reduce the cost of fusion plants to a figure that was 20% lower than that projected for an ALWR facility should all the present uncertainties surrounding such a plant be resolved in the most satisfactory manner. For a fusion facility to be readily accepted, it must offer compelling advantages over its competitors, the most important factor being that it is less expensive. (Page 3 - Element 1.b: Economics).

It was stressed that the issue of primary importance for any new power plant is not that of technology but rather that of money. And, a major issue that will affect the overall costing is that of licensing; a large cost penalty is associated with the licensing of fission plants. Simplifying the licensing process will yield a high economic payoff because the licensing process occurs at the end of construction when all of the design and construction costs have been incurred. Not only are errors more difficult and costly to correct at this time, but the cost of money, debt service, is at a maximum too.

III.3 ON LOAD-FOLLOWING

If it is achievable, the capability for load following would be an advantage of a fusion plant. Utilities experience trouble with fossil plants with respect to load-following; maintenance problems become severe due to the thermal excursions that are involved. If there is sufficient fusion plant capacity in the mix, the necessity for load-following by the fossil plants will be avoided. However, the decision to purchase any new plant is based upon its economics. Once purchased, if it can load-follow with no penalty, that is looked upon as a bonus; it does not enter into the initial decision.

III.4a ON LICENSING ISSUES

The emphasis with respect to the licensing of a fusion plant should be based on the fact that fusion and fission are entirely different processes. Every attempt should be made to avoid confusing the two, which means that verbiage that applies to fission and that has hitherto been applied, by analogy, to fusion, should be avoided. There are genuine differences between fusion and fission, and every attempt must be made to differentiate, honestly, between the processes. The committee accepted that this would be an up-hill task since, with the exception of those in the Office of Fusion Energy, a mind-set already existed in the government that equated the two.

It was agreed that the development of low-activation materials was important to fusion and would have a positive impact upon licensing; fusion will generate Class C waste, but the waste will not be comparable to fission products and actinides, and fusion should strive for the same treatment as hospitals from the point of view of radioactive waste disposal. While there was a growing confidence within the interested community that low-activation materials could become a reality, there was concern that too little priority is being placed on these materials by the fusion program. While it is entirely possible that such materials could indeed be developed over the next 50 years, more emphasis needs to be placed upon their development to ensure their timely availability, and the OFE must be persuaded of the need for priority here.

It was pointed out that, on the positive side, the budget for 1995 has been changed to enhance low-activation materials research and there is now a much greater awareness in OFE of the need to accelerate this program, although it is still not funded at a level that is considered acceptable.

It was suggested that during the establishment of fusion licensing criteria, one should work through Title 10CFR50, part by part, and eliminate everything that is not relevant to fusion. It was noted in the discussion that while it was laudable to try to disassociate fusion from fission, there were similarities between them. Fusion, for example, produces ionizing and nuclear radiation. It also requires remote handling, and the only other power-generation technology that requires this is fission. The counter argument (Larry Papay, Bechtel) was that if fusion were unable to disassociate itself from 10CFR50 and produced high-level waste, then 10CFR50 would definitely apply. There was thus a very real need to reduce the severity of 10CFR50 as it applies to fusion. Hence, while fusion may still have to comply with some parts, including 10CFR20 (which is radiation-related), it really was essential to eliminate as many of the strictly non-applicable appendices (for example, A, B, J, K, R) as possible.

It was suggested that instead of starting with 10CFR50 and arguing for the elimination of the inappropriate parts, a better approach might be for the fusion community to start with a clean slate and to argue and work with the Nuclear Regulatory Commission (NRC) such that only those regulations relevant to the new technology would be retained. The NRC would then be placed in the position of having to justify each proposed regulation. It should result in only those regulations that fusion was unable to justify removal of (e.g. radiation protection standards) being applied to fusion facilities during the licensing process.

The case that is presented to the Board must have both a detailed cost study and a road map through the licensing process. The licensing of fission plants was always the pacing item, and one that was very costly. The cost analysis would of necessity contain a contingency for errors and omissions, plus other unknowns. However, for somethingas open-ended as the licensing process, a true cost is difficult to establish; therefore the total cost becomes uncertain and no decision can be made. The risk associated with the time-cost of money must be taken out of the process. An early site permit is essential. Construction defects can then be removed one-by-one as they occur so that full compliance with regulations may be achieved.

III.4b INPUT ON LICENSING FROM PULSAR TEAM

A summary of licensing issues was presented by the Pulsar Team to the committee. These included reviews of the tokamak magnet power system, the power conversion system, the blanket and fueling system and the auxiliary heating system. Of great significance was the potential inventory of tritium. Calculations show that if 100 grams of tritium is released by the tokamak, then at a distance of 1 kilometer from the point of release, the whole body dose would be 1 rem. Release of the entire vulnerable inventory for the tokamak that was being presented would result in a whole body dose of 8 rem at 1 kilometer. While the acceptable limit is 25 rem, the conclusion was that 8 rem was too near the limit for comfort. Utilities traditionally prefer the level of exposure risk to be at or below 10% of the limit, i.e. at not greater than 2.5 rem whole body dose. Hence the proposed tokamak needed to be improved vis-a-vis tritium release by a factor of two or three, by making a greater part of the tritium inventory non-vulnerable, thus to reduce the vulnerable inventory to 250 grams. It was considered that achieving this would present no real problem.

The advantages of treating a tritium leak in the same manner as some other chemical carcinogen were explored since the safety issues would then become those of a chemical plant, not a nuclear one. The conclusion was that the change in perception necessary to view tritium as a carcinogen rather than as a radio-active species would be difficult to achieve.

In the tokamak under discussion, the decay heat would be spread over a large volume. The only problem elements associated with de-commissioning would be ²⁴Na and tritium. Sodium would be a problem only for tokamaks for which silicon carbide was present in large quantities. Although steels have no sodium problem, the advantages of silicon carbide more than outweigh this one drawback. In any event, ²⁴Na is not a vulnerable inventory and so potential problems are minimized.

The question of whether or not the code applied to N-stamped components was raised. It was concluded that this question should be referred to expert review and, if the code was found to apply, a determination should be made concerning how it might be avoided.

Finally, the point was raised that within three years, DOE may be subjected to OSHA, EPA and NRC oversight. This led to a discussion of how inappropriate regulations might be avoided during the construction of ITER should the site that the U.S. will propose be selected. Table 1 provides a comparison of NRC's "One Stop" regulatory process and that proposed by DOE for ITER.

III.5 ON ITER LICENSING CONSIDERATIONS

A comparison was made between existing and planned U.S. tokamaks, and ITER. The new TPX device planned for Princeton will use no tritium. All reactions will be of the D-D variety. TPX will therefore be easier to license than TFTR was. Hence, unlike ITER, TPX will not push the site issues. Furthermore, ITER is going to set some far reaching precedents and should not be viewed as typical of fusion.

Table 1: NRC/DOE Regulatory Comparison

NRC - `One Stop'

The NRC process is inherently more prescriptive than that used by DOE, probably as a consequence of the environment in which the ultimate decisions of the NRC are implemented.

Early site permit stage.

Design certification stage.

PSAR and FSAR, including a design-specific risk assessment.

A set of proposed inspections, test, analyses and acceptance criteria (ITAAC) for operation must be specified.

The combination of the early site permit, the certified design, and the site-specific features would equal the combined Construction/Operating License (COL).

Public has four opportunities for input:

DOE - as applied to ITER

NEPA compliance mandatory under DOE rules regardless of where it is sited.

An EIS would be needed if it were sited in the U.S.

A PSAR must be completed for DOE to grant approval for construction.

An FSAR, a set of technical safety requirements(TSRs) and a satisfactory operational readiness review (ORR) must be completed for DOE to grant approval for operation.

The public is generally involved only at the initial stage during EIS through hearings
and submittal of public comment.

The choices of materials used in the construction of ITER will be driven by what is already available. The use of such materials in future fusion power plants would be undesirable. Thus, ITER is not the machine upon which to base fusion licensing regulations. This observation is critical: An important part of the Phase II ITER program is its testing mission, during which new materials, and especially those that might be suitable for DEMO blanket engineering, will be evaluated. The materials that are going to be tested in the ITER program will be down-selected for use in the next fusion machine, presumably a DEMO plant. It is the plant constructed from these new materials that should be the one upon which fusion-plant licensing regulations are based. Since ITER is going to be constructed from steels, the strategy should be one licensing route for ITER and another for commercial plants constructed from the new materials.

Regulations for Overseas Plants

In some circumstances, an Environmental Impact Statement (EIS) is required before facilities may be constructed overseas. Examples include facilities at U.S. military establishments that require waste disposal. Even if ITER were to be built overseas, it is possible that the project would need to meet some U.S. licensing regulations. The U.S. program should be cognizant of this.

It was suggested that the licensing process for fusion should be initiated as soon as possible, and before ITER must be dealt with. Then, ITER should be licensed under one set of conditions, with a different set being developed for later machines. The multi-national nature of ITER raised the question of whether international standards should be applied to fusion licensing. In the view of some, the U.S. is currently the world leader in electric power generating technology, and since the rest of the world is very pleased to adopt U.S. licensing rules, the consensus was that the U.S. should develop its own national rules for fusion since in all likelihood these would eventually be adopted worldwide.

IV. Fusion Energy Development and Fusion DEMO

Before proceeding with the design and construction of DEMO, it will be essential that complete agreement is reached on the definitions, characteristics and requirements that constitute a DEMO. The relationship between DEMO and its prototype must be clearly defined; what must be demonstrated and at what scale must be clear. Licensing considerations will influence design choices, as will safety, environmental objectives and waste disposal issues. An experience-base of significant size must be accumulated before proceeding with DEMO. The relationship between the fusion DEMO and fusion power plant pathways must be established, and the timing and nature of utility/industry participation determined. Here utility/industry could perhaps mean a utility-led consortium that includes supplier companies and that is capable of taking full leadership of fusion energy development.

IV.1 GOALS FOR THE FUSION DEMO

Every technology envisioned for commercial fusion power units must be incorporated in DEMO; all systems should be capable of working as an integrated unit at full scale. The DEMO plant should address the issues of dependability, reliability and availability. It should be of sufficient size that it establishes the scalability to the commercial-size units. The DEMO plant should be the one upon which the licensing procedures and rules for commercial fusion power plants are based. DEMO should demonstrate the cost viability of fusion, including the feasibility and acceptable cost of decontamination and decommissioning. The plant should clearly illustrate that the industrial infrastructure exists to serve the needs of the end-user utilities and independent power producers. Finally, DEMO must foster and encourage public acceptance of fusion power generation.

The perceived pathway to fusion power involves a progression from ITER through DEMO to a first-of-a-kind commercial unit (Figure 1). This raised the question of who is going to pay for DEMO, and who is going to pay for the first-of-a-kind commercial plant. Because development costs are going to be high, it is essential that DEMO be close to the first-of-a-kind in order to minimize first-of-a-kind engineering costs and to establish a technology data base upon which market decisions may be based. Currently, it is planned that the DEMO machine be built in a cost-sharing mode between the government and industry, so that the additional objective of establishing fusion engineering expertise within U.S. industry be achieved.

IV.2 The Role of ITER

It is the task of ITER and the balance of the U.S. fusion program to ensure that the U.S. is fully prepared to move on to DEMO in a timely manner. The fusion systems studies Starlight program will, within the next eighteen months, identify the issues that could be addressed by ITER and by the balance of the program, before moving to DEMO. If ITER is unable to provide all the information, then another machine might be needed in-between ITER and DEMO which will, of necessity, delay DEMO. This raised the point that if one were to wait until the conclusion of the eighteen-month study before providing results, the information would not be available in time to influence ITER. The compromise solution dictates that the fusion system studies Starlight program will make partial inputs to ITER on a regular basis until it is complete. It is anticipated that other national programs will act likewise, and that the programs of the overseas partners will also contribute to ITER on a continuous basis.

The minimum performance that DEMO must develop to satisfy concerns about scalability to the first-of-a-kind commercial power plant was discussed. Performance scalability was not seen as providing much of a problem. Of far greater concern were items such as the divertor which may not scale. The step from ITER to DEMO would appear to be simple since, perhaps for the first time, the Engineering Test Reactor (Namely, ITER) would be significantly larger than the machine that follows it.

IV.3 The Role of DEMO

It was considered likely that the most prominent factor constraining the size of DEMO would be the need for economic production of energy. From the utilities point of view, it is essential that DEMO make money. Since the U.S. government will probably pay 50% of the cost the DEMO facility, a premium of 20% on the cost of the electric energy produced by it would be acceptable. However, the premium that could be paid for DEMO's energy was highly susceptible to any change in the government's share of the facility cost. One could pay twice as much for DEMO as for the first-of-a-kind commercial machine and still get the same payback because the government pays for half of DEMO. To the extent that DEMO is less than half the cost of the first-of-a-kind machine, a better than normal payback could be expected.

Since the DEMO will be operated by utility personnel, it will have to look like, and operate similarly to, the first commercial machine. It must demonstrate construction and O&M cost advantages, and an acceptable life-cycle cost of energy. All must be capable of being achieved in a benign regulatory environment. The machine must demonstrate easy operability and high operational reliability, and must meet the criterion of no more than one uncontrolled shut-down (or one pulse failure) per year. It is a cultural imperative that the machine demonstrate that it is a low man-rem device. In essence this means that at least one complete blanket replacement must occur, which must be safe, and economically so. DEMO is likely to require two complete blanket changes during the first ten or so years of operation. Thus the man-rem issue should be clarified before any commitment to the first-of-a-kind machine is needed.

The fuel cycle characteristic must be demonstrated, and the life-cycle cost, including decontamination and decommissioning, must be determined.

Finally, since industry will have to construct the device, industry's interest in the fusion program will need to be maintained over a very long time period. The test elements for the ITER program should be designed and constructed by industry.

V. Date of the Next Meeting

It was agreed that the next meeting will be held in June. It will be a two-day meeting, with a third day being required for travel. Committee members will be polled to determine which of the periods June 1, 2, and 3 or June 22, 23, and 24 is the more convenient.

The meeting will focus on a comparison between the characteristics of a steady-state machine and those of a pulsed machine. In addition, the details of the preferred development path to DEMO will be reviewed.

Appendix I: Up-Date of the Status of Fusion and Near-Term Plans;

Remarks by Dr. David O. Overskei, Vice President, General Atomics, and comments by, and dialog with, committee members.

Dr. Overskei started by dealing with the reasons why an industry should be interested in joining in a venture such as fusion, that is so far away from commercial reality. Participation in intellectually demanding science and technology research enables a company to build up a reputation in the field which spills over to benefit the rest of the company, and opens doors for it in other areas of technology. In fusion, it is no longer science or improvements in science that are needed and important, but rather developments and improvements in technology, manufacturability and reliability are required. These areas should be of more interest to industry. In Japan, for example, it costs companies money to participate in the fusion program, but the benefits are seen to be worth the cost. There is real promise in fusion and many opportunities for industry. An interest shown by utilities in fusion would encourage industry.

Fusion will never come to reality unless the public can be made to accept fission. The climate for light-water reactors can be improved, not in terms of technology and cost, but rather in terms of perceived risk and in the area of licensing.

The remaining problems in fusion will not be solved by further improvements in confinement (the ability to retain heat in the plasma). Up until now, fusion performance has been limited by plasma technologies. This has changed, and performance is limited by materials availability, the handling of thermal loads, magnet technologies, etc. ITER, for example, already has first wall materials problems and a divertor problem, and cannot take advantage of the upper limit achieved for confinement.

ITER is the size it is because it incorporates some conservatism with respect to performance, and because it must be constructed from materials that are available today. The device will be operated at about 60% of capacity, which means it will be quite reliable. All of the margin is in the technology; hence the machine is larger than it really need be.

Until recently, the fusion program was led by scientists and physicists, largely at the national laboratories and universities, but that is changing. The technology of the application needs to be developed and, in future, if plasmas

Appendix II: Meeting Attendees

Committee Members Attending:

Ex Officio Members:

Observers:

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