ML23118A345
ML23118A345 | |
Person / Time | |
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Issue date: | 06/13/2023 |
From: | Liliana Ramadan NRC/NRR/DEX/ELTB |
To: | |
Shared Package | |
ML23118A358 | List: |
References | |
RG 1.212 Rev 2 DG-1418 | |
Download: ML23118A345 (3) | |
Text
Responses to Public Comments on Draft Regulatory Guide (DG)-1418 Sizing Large Lead-Acid Storage Batteries Revision 2 to Regulatory Guide 1.212 On March 6, 2023, the U.S Nuclear Regulatory Commission (NRC) published a notice in the Federal Register (88 FR 13735) that Draft Regulatory Guide (DG)-1418 (Proposed Revision 2 to Regulatory Guide (RG) 1.212) was available for public comment. The public comment period ended on April 5, 2023. The NRC received comments from individuals listed in the table below. This document identifies how the NRC dispositioned the comments received. The comments are quoted verbatim in italics.
Comment No. Commenter ADAMS Accession No.
1 Anonymous ML23067A070 2 Tania Martinez Navedo ML23074A002 3 Anonymous ML23074A015 4 Curtis Ashton ML23074A016 Comment 1:
This rule should be reviewed and revised over the necessary comments and standard procedures in the legal correct form of action. The sizing of lead is similar to sizing poison against society in numerical forms. Nature and life matters and destroying matter around us by producing a lead heavy sized battery will not help the environment but slowly destroy it and the people around it. The sizing for lead-acid batteries should be replaced with another power source that both helps the environment and its people that protect it.
NRC Response:
This comment is outside the scope of this RG. The comment opposes the use of lead. The guidance in this RG is voluntary and applicants/licensees may choose alternative power sources to meet their requirements. This RG provides guidance to applicants and licensees for defining the direct current (dc) load and sizing of large lead-acid batteries to supply dc power to applications during the full range of operating and emergency conditions for production and utilization facilities. No changes were made toas a result of this comment.
Comment 2:
The last paragraph in the background section states:
IEEE Std. 485-2020, section 4.2.5, Duty Cycle Diagram, states that the total time span of the duty cycle is determined by the requirements of the installation. This duty cycle time depends on the type of production and utilization facility designactive or passive. The duty cycle time is typically discussed in a plant safety analysis report. For facilities that are active, the battery duty cycle should cover both design-basis accidents (DBAs) and station blackout (SBO) scenarios (with a permitted load shedding scheme). For DBAs, since an emergency diesel generator (EDG) or other onsite emergency power source is assumed to be available within approximately 10 seconds to recharge the battery, some facilities have sized the vital batteries considering a duty cycle of less than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> duration. However, an EDG or onsite emergency power source may be out of service at the time of an accident concurrent with the loss of offsite power. It may take up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to switch the associated battery charger to an alternate power source. Therefore, for active designs, the vital batteries should be sized for the worst-case duty cycle,
consisting of either a minimum of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for the DBAs or the analyzed SBO duration (with a permitted dc load shedding scheme). This guidance does not apply to the EDGs or onsite emergency power sources own battery if provided separately (which is exclusively sized based on the starting requirement of the EDG or onsite emergency power source, such as field flash).
This paragraph may cause confusion since passive plants may still need to design for DBA and SBO and this paragraph doesnt state as such - really, it doesnt provide sufficient guidance for passive plants. Passive plants and advanced Rx will have to size their batteries, based on the safety analysis (i.e. for what events they are needed - DBA, SBO, AOO, etc).
I would recommend revising the paragraph as follows:
IEEE Std. 485-2020, section 4.2.5, Duty Cycle Diagram, states that the total time span of the duty cycle is determined by the requirements of the installation. This duty cycle time depends on the type of production and utilization facility design, andactive or passive.
The duty cycle time is typically discussed in a plant safety analysis report. For facilities that are active, the battery duty cycle should cover both design-basis accidents (DBAs) and station blackout (SBO) scenarios (with a permitted load shedding scheme). For DBAs, since an emergency diesel generator (EDG) or other onsite emergency power source is assumed to be available within approximately 10 seconds to recharge the battery, some facilities have sized the vital batteries considering a duty cycle of less than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> duration. However, an EDG or onsite emergency power source may be out of service at the time of an accident concurrent with the loss of offsite power. It may take up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to switch the associated battery charger to an alternate power source. Therefore, for active designs, the vital batteries should be sized for the worst-case duty cycle, consisting of either a minimum of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for the DBAs or the analyzed SBO duration (with a permitted dc load shedding scheme).
This guidance does not apply to the emergency diesel generators (EDGs) or onsite emergency power sources own battery if provided separately (which is exclusively sized based on the starting requirement of the EDG or onsite emergency power source, such as field flash).
NRC Response:1 The staff agrees with the comment to provide general guidance applicable to the type of production and utilization facility design. DG-1418 was modified as recommended by the commenter.
Comment 3:
I believe it would be beneficial to approve of this change in regulation. A lot of things have changed, and due to the main reason for this request being an attempt to make shipping and the overall process of battery transport and sale more consistent, I personally see this change as a good thing. Bigger batteries would result in longer performance due to having a larger capacity. This would allow facilities to produce larger batteries, which means smaller production rates, but more efficient and longer-lasting batteries. From an economic standpoint, the initial price of the battery would increase, but it would allow for a longer usage time, saving the producing company time on not making so many, and save the customer from having to buy batteries quite as frequently. Overall, I see no harm in implementing this rule, as the pros would outweigh the cons and could benefit society.
1 Although the comment was submitted by a current NRC employee, the comment was treated as submitted by a member of the public. The NRC employee submitting the comment has no official responsibility for and did not work on the RG.
NRC Response:
The commenter generally supports the revision, and no change was made to DG-1418 as a result of this comment. For completeness, the staff notes that this RG is not associated with any changes in Commission rules or regulations. The RG provides voluntary guidance to applicants and licensees for defining the dc load and sizing of large lead-acid batteries to supply dc power to applications during the full range of operating and emergency conditions for production and utilization facilities.
Comment 4:
In the 4th paragraph of page 4, the guide notes that IEEE 484 and several other IEEE standards are helpful when sizing lead-acid batteries. Since 484 refers directly to IEEE 1635 / ASHRAE 21 for ventilation calculations, it would be good to include this IEEE/ASHRAE document in there as well.
NRC Response:
The staff agrees with the comment and modified DG-1418 to add a reference for Institute for Electronics and Electrical Engineers (IEEE)/American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) 1635-2022, Guide for the Ventilation and Thermal Management of Batteries for Stationary Applications. IEEE/ASHRAE 1635-2022 provides ventilation calculations that are associated with IEEE Standard 484, IEEE Recommended Practice for Installation Design and Installation of Vented Lead-Acid Batteries for Stationary Applications.