Batteries, Battery failure, dangers of nuclear, emergency backup power, Emergency Batteries, emergency battery failure, EnerSys, failures, Fukushima, hurricane, Hurricane Hermine, Hurricane Hermine track, lead batteries, legal liability, liability, nuclear, nuclear accident, nuclear accident liability, nuclear disaster, nuclear energy, nuclear industry, nuclear power, Nuclear Power Station, Nuclear Power Station Emergency Backup, Power Outages, risk management, US NRC, USA
On Sept. 1st, 2016 EnerSys notified the US NRC of potential battery failures at nuclear power stations apparently due to how their batteries interact with the nuclear power station connections. Why are they trying to absolve themselves of responsibility? Why are they not working with their customers, the nuclear utilities, to make sure that this integral part of nuclear reactor safety works? Batteries are needed as emergency backup power. Did the timing have to do with Hurricane Hermine entering the Gulf of Mexico, where it threatened numerous nuclear power stations?
According to the US DOE: “When an earthquake or other emergency disrupts normal power supplies at a nuclear power plant, a backup power system must be available for controlling the plant and safely shutting down the reactor.”
This image is found in the same article. These are of a different brand, however.
According to Dr. David Lochbaum, “Per design, batteries provided direct current (dc) electrical power for a bare-bones minimal subset of emergency equipment.” http://allthingsnuclear.org/dlochbaum/nuclear-station-blackout This includes emergency cooling to prevent a meltdown.
Why did EnerSys choose to send out this notification as Hurricane Hermine approached landfall on a track with multiple nuclear power stations in its sights? Why did they send it out in the peak of hurricane season? To try to avoid legal liability? Did one or more nuclear power stations test batteries in preparation for Hurricane Hermine and find them dead?
Although Hermine is a comparatively weak storm, even weak hurricanes and their spin-off tornados are known to generally cause widespread power outages. Thus the need for backup power. Indeed, such was the case for Hurricane Hermine, where hundreds of thousands lost power in multiple states. https://web.archive.org/web/20160903054301/http://www.breakingnews.com/topic/power-outages/ No hurricane, large or small, should be underestimated. They must be treated with caution and respect. While having common characteristics, each hurricane and tropical storm appears to be somewhat unique, and one must be prepared for anything. Not only did Hurricane Hermine cause widespread power outages, it caused torrential rainfall, as well.
Furthermore, so messed up are the electrical systems of most nuclear power stations (defective breakers, open phase defects) that even a nearby lightening strike caused a scram, which led to a loss of cooling, earlier this year: https://miningawareness.wordpress.com/2016/02/18/lightening-scrammed-nuclear-reactor-lost-cooling-off-for-weeks-on-again-now-off-usnrc-inspection/
The EnerSys Notice to the US NRC: “Notification Date: 09/01/2016, Notification Time: 14:51 [ET]” Shortly before, at 1 pm ET, the National Hurricane Center issued the following: “BULLETIN TROPICAL STORM HERMINE SPECIAL ADVISORY NUMBER 17…CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016 1200 PM CDT THU SEP 01 2016… DISCUSSION AND 48-HOUR OUTLOOK..
At 1200 PM CDT (1700 UTC), the center of Tropical Storm Hermine was located near latitude 27.8 North, longitude 85.6 West. Hermine is moving toward the north-northeast near 14 mph (22 km/h), and this motion with a slight increase in forward speed is expected during the next day or so. On the forecast track, the center of Hermine will be near the Florida coast in the hurricane warning area tonight or early Friday.
Maximum sustained winds are near 70 mph (110 km/h) with higher gusts. Additional strengthening is anticipated, and Hermine is expected to be a hurricane by the time landfall occurs.
Tropical-storm-force winds extend outward up to 185 miles (295 km), mainly to the northeast and southeast of the center. The estimated minimum central pressure is 989 mb (29.21 inches).
HAZARDS AFFECTING LAND
WIND: Hurricane conditions are expected to reach the coast within the warning area beginning tonight. Winds are expected to first reach tropical storm strength by this afternoon, making outside preparations difficult or dangerous. Preparations to protect life and property should be rushed to completion. Tropical storm conditions are expected to begin within the warning area along the Atlantic coast on Friday, and spread northward through Friday evening. Tropical storm conditions are possible in the tropical storm watch area by Friday night and Saturday.
STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. There is a danger of life-threatening inundation within the next 12 to 24 hours along the Gulf coast of Florida from Indian Pass to Longboat Key…
RAINFALL: Hermine is expected to produce storm total rainfall accumulations of 5 to 10 inches over portions of northwest Florida and southern Georgia through Friday, with possible isolated maximum amounts of 20 inches. On Friday and Saturday, Hermine is expected to produce totals of 4 to 8 inches with isolated maximum amounts of 10 inches possible across portions of eastern Georgia, South Carolina, and eastern North Carolina through Saturday. These rains may cause life-threatening flash flooding.
TORNADOES: A few tornadoes are possible this afternoon into Friday morning over north Florida and southeast Georgia. The tornado risk will continue across the eastern Carolinas from Friday morning into Friday night.” https://web.archive.org/web/20160903144732/http://www.nhc.noaa.gov/archive/2016/al09/al092016.public.017.shtml? Hermine had entered the Gulf of Mexico a couple of days before, and once there, even if it changed course, would put at risk numerous nuclear power stations.
Here’s what the Enersys notice says:
“21 – POTENTIAL FAILURE OF BATTERY SYSTEM CONNECTIONS
“This letter will serve as notification from EnerSys to the United States Nuclear Regulatory Commission of an identified deviation in published literature information. The literature defines requirements for resistance in both cell to cell and cell to terminal connections in supplied battery systems. High connection resistance causes increased cell voltage drop and a potential failure to meet run time requirements.
“Internal investigation by EnerSys confirms that no defects exist in systems tested before shipment to customer utilities as internal documented procedures define correct parameters. However, the potential of less than desired performance exists if the values noted in the literature are used during installation and test at utility sites.
“EnerSys does not have the ability to evaluate if a defect exists at customer utilities so per the provisions of Part 21, notification is being made to both the Commission and affected EnerSys customers.” http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2016/20160902en.html
Such faulty connections can lead to failure, which are unacceptable in the context of a nuclear power station:
Problem = High connection resistance, means that the wiring and connectors are not made or installed properly
Location = cell to cell and cell to terminal connections.
Consequence = battery overload or premature drainage. The overload can cause corrosion and a premature energy drainage so the battery will not work when needed in an emergency (or not for the duration expected). An overloaded battery may even explode.
For the AP 1000, the UK’s Nuclear Regulator states:
“Westinghouse’s safety claims and arguments are set out in the PCSR. These include the following claims and arguments:
The main AC system does not perform any safety function.
The battery backed Class 1E direct current (DC) and Uninterruptible Power Supply (UPS) systems provide reliable power for the safety systems, structures and components needed for shutdown of the plant.
The standby diesel generators are not safety related as they do not support safety critical plant“. http://www.onr.org.uk/new-reactors/reports/step3-ap1000-electrical-systems-assessment.pdf
The Brookhavn National Lab and the US NRC undertook “Evaluation of Battery and Battery Charger Short-Circuit Contributions to a Fault on the DC Distribution System at a Nuclear Power Plant” (Task 1 Report, Lit Review) in 2015. Excerpt: “Inherent in designing and maintaining short-circuit protection in a DC distribution system protection is knowing what the contributions are from the station battery and battery charger(s), the major sources of direct current to a fault on the DC distribution system. There is an extensive amount of literature dealing with this subject in the form of industry guidance or standards, journal articles, and test reports. The purpose of this BNL technical report is to review these sources and summarize the information that is relevant to better understanding the expected contributions from batteries and battery chargers in response to a fault on a DC distribution system at a nuclear power plant. The review of the literature revealed several interesting factors associated with this general subject including:
1. Industry guidance and standards (summarized in Table 1) differ somewhat with regard to the magnitude of the short-circuit currents to be expected from a vented lead acid battery and the combined effect from the battery charger and battery when they are connected in parallel (the typical configuration for a nuclear power plant). Some publications indicate that a conservative rule of thumb approach is sufficient while others recommend more precise calculations that take into account DC distribution system resistance and inductance.
2. These same industry standards are based on a limited amount of testing and other empirical data. IEEE 141-1993 states that “Simplified procedures for the calculation of DC short-circuit currents are not well established.” Since many of the DC distribution systems in the current commercial nuclear reactor fleet were designed before 1993, there may not have been a uniform approach taken to calculating the expected contributions from battery chargers and batteries when designing the short-circuit protection schemes for the DC distribution system.” “EVALUATION OF BATTERY AND BATTERY CHARGER SHORT-CIRCUIT CURRENT CONTRIBUTIONS TO A FAULT ON THE DC DISTRIBUTION SYSTEM AT A NUCLEAR POWER PLANT TASK 1 REPORT: LITERATURE REVIEW” March 2015 Prepared by Brookhaven National Laboratory Nuclear Sciences and Technology Department Upton, New York 11973 BNL Project Manager – Bill GuntherPrepared for U.S. Nuclear Regulatory Commission Project HQ-60-14-D-0023 NRC Project Manager – Liliana Ramadan https://www.bnl.gov/isd/documents/88634.pdf