View source for Information Notice 1998-07, Offsite Power Reliability Challenges from Industry Deregulation

{{Adams
| number = ML031050278
| issue date = 02/27/1998
| title = Offsite Power Reliability Challenges from Industry Deregulation
| author name = Roe J W
| author affiliation = NRC/NRR
| addressee name = 
| addressee affiliation = 
| docket = 05000003, 05000010, 05000029, 05000133, 05000155, 05000171, 05000206, 05000213, 05000219, 05000220, 05000237, 05000244, 05000245, 05000247, 05000249, 05000250, 05000251, 05000254, 05000255, 05000259, 05000260, 05000261, 05000263, 05000265, 05000266, 05000267, 05000269, 05000270, 05000271, 05000272, 05000275, 05000277, 05000278, 05000280, 05000281, 05000282, 05000285, 05000286, 05000287, 05000289, 05000293, 05000295, 05000296, 05000298, 05000301, 05000302, 05000304, 05000305, 05000306, 05000309, 05000311, 05000312, 05000313, 05000315, 05000316, 05000317, 05000318, 05000320, 05000321, 05000322, 05000323, 05000324, 05000325, 05000327, 05000328, 05000329, 05000330, 05000331, 05000333, 05000334, 05000335, 05000336, 05000338, 05000339, 05000341, 05000344, 05000346, 05000348, 05000352, 05000353, 05000354, 05000361, 05000362, 05000364, 05000366, 05000368, 05000369, 05000370, 05000373, 05000374, 05000382, 05000387, 05000388, 05000389, 05000390, 05000391, 05000395, 05000397, 05000400, 05000409, 05000410, 05000412, 05000413, 05000414, 05000416, 05000423, 05000424, 05000425, 05000437, 05000438, 05000439, 05000440, 05000441, 05000443, 05000444, 05000445, 05000446, 05000454, 05000455, 05000456, 05000457, 05000458, 05000461, 05000482, 05000483, 05000498, 05000499, 05000508, 05000528, 05000529, 05000530
| license number = 
| contact person = 
| document report number = IN-98-007, NUDOCS 9802240067
| document type = NRC Information Notice
| page count = 7
}}
{{#Wiki_filter:X 71 C sa'UNITED STATES NUCLEAR REGULATORY

COMMISSION

===OFFICE OF NUCLEAR REACTOR REGULATION===
WASHINGTON, D.C. 20555-0001 February 27, 1998 NRC INFORMATION

NOTICE 98-07: OFFSITE POWER RELIABILITY

CHALLENGES

===FROM INDUSTRY DEREGULATION===

==Addressees==
All holders of operating

licenses for nuclear power reactors except those who have ceased operations

and have certified

that fuel has been permanently

removed from the vessel.

==Purpose==
The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to alert addressees

to a potential

concern relating to electric power industry deregulation

that could adversely

affect the reliability

of offsite power sources, i.e., power from the transmission

system grid to nuclear power plants. It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, as appropriate.

===However, suggestions===
contained

in this information

notice are not NRC requirements; 
therefore, no specific action or written response to this notice is required.Description

of Circumstances

On July 11, 1989, safety systems at Virgil C. Summer Nuclear Station experienced

a sustained degraded voltage condition

and as a result the safety buses were automatically

transferred

from the offsite power system to onsite standby diesel generators.

The degraded condition

was caused by a turbine trip and deficiencies

in the offsite power system's transmission

network equipment.

The transfer of power supplies was initiated

by operation

of degraded voltage protective

relays, as designed.

Non-safety

system loads remained operable while being powered for approximately

1 hour from the degraded offsite power source. (LER 50-395/89-012)
On November 5, 1991, the licensee for Arkansas Nuclear One, Units 1 and 2 reported that, had its 500kV auto-transformer

been lost during summer peak conditions, the 161kV system might not have been able to maintain adequate voltages to support the operation

of the safety system loads of both units. (LER 50-313/91-010)
On April 15, 1992, Northeast

Nuclear Energy Company reported that under certain operating conditions

of the transmission

network (i.e., during heavy load conditions), a failure of transmission

system equipment

may cause a trip of all three Millstone

units and a loss of offsite power to the station. This operating

condition

was precipitated

by the economic displacement

of oil-fired

generating

units by non-utility

generators

and by the addition of other generating

capacity (Seabrook

and Hydro-Quebec) 
to the transmission

network. (LER 50-245/92-020)
?PD 1re-F Normf, 1g-0o7 80a.2 7 q ~ r 1l~lill~lill~lill~lililuill1!\i

IN -07 February 27, 1998 On April 14, 1993, Wisconsin

Public Service Corporation

reported that under certain transmission

line contingencies, a potential

existed for the Kewaunee Nuclear Power Plant grid to become unstable and cause all offsite power sources into the plant to trip. (Ref: LER 50-305/93-010)
On December 30, 1993, Northeast

Nuclear Energy Company reported that under certain operating

conditions

of the transmission

network (i.e., Millstone

Units 2 and 3 off line), the transmission

network may not have sufficient

capacity to permit the continued

operation

of safety system loads from offsite sources following

a trip of Millstone

Unit 1. (LER 50-245/94-001)
On August 8, 1995, Pacific Gas and Electric Company (PG&E) reported that under certain operating

conditions (i.e., a high system load with a specific 230kV transmission

line out of service), the transmission

network may not have sufficient

capacity to permit the continued operation

of the safety system loads from offsite sources following

a trip of one of the two Diablo Canyon units. (Ref: LER 50-275/95-007)
On August 10, 1996, a transmission

line sagged into a tree in Oregon creating a ground fault that progressed

into a major fault on the western Interconnection.

The subsequent

transient

resulted in the tripping of both Diablo Canyon, Units 1 and 2 (LER 50-275/96-012) 
and Palo Verde, Units 1 and 3 (LER 50-528/004).

During the summer of 1997, concerns were expressed

about the impact of electric peak conditions

on the offsite power sources for nuclear power plants located in the Midwest and New England. In addition, the licensee for Clinton nuclear station sought an exemption

from offsite power regulatory

requirements

because of its analysis that offsite power would become inadequate

under certain summer peak conditions

following

the loss of the nuclear unit.Recent NRC inspection

findings and Licensee Event Reports have indicated

instances

when grid stability

analyses had not been updated by the licensees

to reflect changes in the grid power system. Office for Analysis and Evaluation

of Operational

Data study C97-01, "Grid Performance

Factors" dated March 20, 1997, identified

a Oneed to monitor grid conditions

on a regular basis." Discussion

In 1988, NRC issued the station blackout (SBO) rule. The requirements

of 10 CFR 50.63, "Loss of All Alternating

Current Power," specify that each light-water-cooled

nuclear power plant be able to withstand

and recover from an SBO (i.e., a loss of offsite and onsite emergency

ac power sources) for a specified

period. The NRC review of licensees' 
analyses to assess the vulnerability

of offsite power and the time required for recovery indicated

that for most nuclear power plant sites the grid was stable and reliable.Historically, grid control is decentralized

and each utility or a small group of utilities

forms a control area containing

customers

for which it Is jurisdictionally

responsible.

The control areas form reliability

councils that establish

operating

standards

by consensus.

These agreements, in turn, became the factors that determine

the reliability

of the grid and the bases for the availability

of the offsite power system. Although the grid operating

standards

that evolved in the past provided reasonable

grid reliability, events like those discussed

herein reveal vulnerabilities

of the electrical

grid either through actual challenges

or through licensee's

analyses to assess the adequacy of the offsite power system.

INS '7 Feb,--dry

27, 1998 The present grid management

may be dismantled

or restructured

by two factors that are emerging: 
non-utility

generation

and deregulation.

It Is anticipated

that in the future, power suppliers, whether utilities

or independent

power producers, will actively compete for sales to customers

who may be located anywhere on the power grid. This option creates multiple combinations

of generating

units going on and off the grid based on economic and performance

related consequences.

Regional grid control could be the responsibility

of centralized

independent

system operators (ISOs). The responsibilities

and authority

of an ISO are yet to be defined, but It is expected that the ISO, or a similar entity, will be charged with maintaining

grid reliability

to facilitate

the marketing

of power. It is uncertain

how the historic mechanisms

for reliable operation

will change under the new grid operational

structure.

The Department

of Energy has sponsored

a Task Force on Electric System Reliability

to examine the implications

of industry deregulation

on the Nation's electric power supply.The capacity and capability

of the offsite power system for each nuclear power plant could be significantly

influenced

by the decisions

emerging from these forthcoming

changes. Since the capability

of the offsite power cannot be tested except when challenged

in an actual event, the design bases of the offsite power can only be assured through an enveloping

analysis that accounts for the full spectrum of grid loading and transient

conditions

that support the operability

of safety systems. The NRC Standard Review Plan Section 8.2 provides current guidance for assessing

the adequacy of the offsite power system. It addresses

grid analyses that demonstrate

acceptable

voltage and frequency

when subjected

to scenarios

involving

loss of nuclear unit generation, loss of the largest other unit, or loss of the most critical transmission

line.Although the above events discussed

may not demonstrate

present generic weaknesses

in licensees' 
processes, it is vital that licensees

continue to ensure that the design bases with respect to the reliability

and stability

of the offsite power sources do not degrade during the life of the nuclear facility.

The capacity and capability

of the offsite power system for nuclear power plants are important

elements to be factored into the management

of the changes resulting

from industry deregulation.

This information

notice requires no specific action or written response.

If you have any questions about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.orig /s/'d by Jack W. Roe, Acting Director Division of Reactor Program Management

===Office of Nuclear Reactor Regulation===
Technical

Contacts: 
Ronaldo V. Jenkins, NRR Thomas Koshy, NRR 301415-2985 
301415-1 176 E-Mail: rvj2nrc.gov

E-Mail: txk@nrc.gov

A-1T E~A FiL ;1 JAckETF Attachment: 
Ust of recently issued Information

Notices OGC Concurrence (R. K Hoefling) 
214198, PGEB Id 2/17198 (T. Essig), AEOD Idc 2/12/98 (E.Rossi) 
& Tech Editor 1/27/98 DOCUMENT NAME: S:%DRPM SEC\98-07.IN

-SEE PREVIOUS CONCURRENCE

To receive a copy of Nhis document, Indicate In the box C=Copy wlo attachmentlenclosure

E=Copy with attachmenUendosure

N = No copy l OFFICE PECB I EELB I IEELB I PECB L PECB I DRPM A NAME TKoshy* RJenkins* 
JCalvo* RDennig* SRichards* 
JRoe*DATE 2/2/98 j 2/2/98 j 2/2/98 2/10/98 2/11/98 2/17/98 OFFICIAL RECORD COPY

Attachment

IN 98-07 February 27, 1998 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 98-06 Unauthorized

Use of Ucense to 2/19198 All NRC licensees

authorized

to Obtain Radioactive

Materials, And Its Implications

Under The Expanded Title 18 of the U.S. Code Environmental

===Qualification===
Deficiency

for Cables and Containment

Penetration

Pigtails possess licensed material 97-45, Supp. 1 2/17/98 All holders of operating licenses for nuclear power reactors except those licensees who have permanently

ceased operations

and have certified

that the fuel has been permanently

removed from the reactor vessel 98-05 98-04 98-03 98-02 98-01 97-91 97-90 Criminal History Record Information

1997 Enforcement

Sanctions

for deliberate

Violations

of NRC Employee Protection

requirements

Inadequate

Verification

of Overcurrent

Trip Setpoints

in Metal-Clad, Low-Voltage

Circuit Breakers Nuclear Power Plant Cold Weather Problems and Protective

Measures Thefts of Portable Gauges Recent Failures of Control Cables Used on Amersham Model 660 Posilock Radiography

===Systems Use of Nonconservative===
Acceptance

Criteria in Safety-Related

Pump Surveillance

Tests 2111/98 2/9/98 1/21/98 1/21/98 1/15/98 12/31/97 12/30/97 All holders of operating licenses for power reactors All U.S. Nuclear Regulatory

Commission

licensees All holders of operating

licenses for nuclear power reactors All holders of operating

licenses for nuclear power reactors All portable gauge licensees All industrial

radiography

licensees All holders of OLs for nuclear power reactors except those who have ceased operations

and have certified

that fuel has been permanently

removed from the vessel OL = Operating

License CP = Construction

Permit

IN9' Y , Feb~Uyxx, 1998 The present grid management

may be dismantled

or restructured

by two factors that are emerging: 
non-utility

generation

and deregulation.

It Is anticipated

that in the future, power suppliers, whether utilities

or independent

power producers, will actively compete for sales to customers

who may be located anywhere on the power grid. This option creates multiple combinations

of generating

units going on and off the grid based on economic and performance

related consequences.

Regional grid control could be the responsibility

of centralized

independent

system operators (ISOs). The responsibilities

and authority

of an ISO are yet to be defined, but it Is expected that the ISO, or a similar entity, will be charged with maintaining

grid reliability

to facilitate

the marketing

of power. It is uncertain

how the historic mechanisms

for reliable operation

will change under the new grid operational

structure.

The Department

of Energy has sponsored

a Task Force on Electric System Reliability

to examine the implications

of industry deregulation

on the Nation's electric power supply.The capacity and capability

of the offsite power system for each nuclear power plant could be significantly

influenced

by the decisions

emerging from these forthcoming

changes. Since the capability

of the offsite power cannot be tested except when challenged

in an actual event, the design bases of the offsite power can only be assured through an enveloping

analysis that accounts for the full spectrum of grid loading and transient

conditions

that support the operability

of safety systems. The NRC Standard Review Plan Section 8.2 provides current guidance for assessing

the adequacy of the offsite power system. It addresses

grid analyses that demonstrate

acceptable

voltage and frequency

when subjected

to scenarios

Involving

loss of nuclear unit generation, loss of the largest other unit, or loss of the most critical transmission

line.Although the above events discussed

may not demonstrate

present generic weaknesses

in licensees' 
processes, it is vital that licensees

continue to ensure that the design bases with respect to the reliability

and stability

of the offsite power sources do not degrade during the life of the nuclear facility.

The capacity and capability

of the offsite power system for nuclear power plants are important

elements to be factored into the management

of the changes resulting

from industry deregulation.

This information

notice requires no specific action or written response.

If you have any questions about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Jack W. Roe, Acting Director Division of Reactor Program Management

===Office of Nuclear Reactor Regulation===
Technical

Contacts: 
Ronaldo V. Jenkins, NRR Thomas Koshy, NRR 301-415-2985 
301-415-1176 E-Mail: rvjenrc.gov

E-Mail: txk@nrc.gov

Attachment: 
List of recently issued Information

Notices OGC Concurrence (R. K Hoefling) 
2/4198 DOCUMENT NAME: G:ITXK\GRIDIN2.1WPD

-'SEE PREVIOUS CONCURRENCE

To receive a copy of this document indicate In the box C=Copy wlo aftachmentlenclosure

E d: .ATo osure N = No copy[OFFICE lPECB lI EELB 1 _ EELB l PECB lI PECB I DRPM NAME TKoshy* RJenkins* 
JCalvo* RDennig* lSRichards'Jle

l DATE j 2/2/98 [2/2/98 2/2/98 j 2/10/98 l- ;1 /98 1/ 1/98_J___A_ 18- .8--OFFICIAL RECORD COPY t CM I Tre

ING' x Febkty xx, 1998 The present grid management

may be dismantled

or restructured

by two factors that are emerging: 
non-utility

generation

and deregulation.

It is anticipated

that in the future, power suppliers, whether utilities

or Independent

power producers, will a6tively compete for sales to customers

who may be located anywhere on the power grid. This option creates multiple combinations

of generating

units going on and off the grid based on economic and performance

related consequences.

Regional grid control could be the responsibility

of centralized

independent

system operators (ISOs). The responsibilities

and authority

of an ISO are yet to be defined, but it is expected that the ISO, or a similar entity, will be charged with maintaining

grid reliability

to facilitate

the marketing

of power. It is uncertain

how the historic mechanisms

for reliable operation

will change under the new grid operational

structure.

The Department

of Energy has sponsored

a Task Force on Electric System Reliability

to examine the implications

of industry deregulation

on the Nation's electric power supply.The capacity and capability

of the offsite power system for each nuclear power plant could be significantly

influenced

by the decisions

emerging from these forthcoming

changes. Since the capability

of the offsite power cannot be tested except when challenged

in an actual event, the design bases of the offsite power can only be assured through an enveloping

analysis that accounts for the full spectrum of grid loading and transient

conditions

that support the operability

of safety systems. The NRC Standard Review Plan Section 8.2 provides current guidance for assessing

the adequacy of the offsite power system. It addresses

grid analyses that demonstrate

acceptable

voltage and frequency

when subjected

to scenarios

involving

loss of nuclear unit generation, loss of the largest other unit, or loss of the most critical transmission

line.Although the above events discussed

may not demonstrate

present generic weakness in licensees' 
process, it is vital that licensees

continue to ensure that the design bases with respect to the reliability

and stability

of the offsite power sources do not degrade during the life of the nuclear facility.

The capacity and capability

of the offsite power system for nuclear power plants are important

elements to be factored into the management

of the changes resulting

from industry deregulation.

This information

notice requires no specific action or written response.

If you have any questions about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Jack W. Roe, Acting Director Division of Reactor Program Management

===Office of Nuclear Reactor Regulation===
Technical

Contacts: 
Ronaldo V. Jenkins, NRR Thomas Koshy, NRR 301-415-2985 
301-415-1176 E-Mail: rvjenrc.gov

E-Mail: txk@nrc.gov

Attachment: 
List of recently issued Information

Notices OGC Concurrence (R. K Hoefling) 
2/4/98 DOCUMENT NAME: G:ITXK\GRIDIN2.1WPD

-SEE PREVIOUS CONCURRENCE

To receive a copy of this document, idicate hi the box C=Copy wlo attachmentlenclosure

E=Copy with attachmentlenclosure

N = No copylOFFICE PECB I EELB _L EELB I -PECB l- DRPM_NAME TKoshyl RJenkins* 
JCalvo* g ~ nig SRichards

JRoel DATE I /== 2/2/9f 1 2/219 i ,I &deg;B9% l I / I9t OFFICIAL RECORD COPY

IN "x February xx, 1998 This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Jack W. Roe, Acting Director Division of Reactor Program Management

===Office of Nuclear Reactor Regulation===
Technical

Contacts: Ronaldo V. Jenkins, NRR 301-415-2985 E-Mail: rvjenrc.gov

Thomas Koshy, NRR 301-415-1176 E-Mail: txkenrc.gov

Attachment: 
List of recently issued Information

Notices DOCUMENT NAME: G:\TXKAGRIDIN2.1WPD

To receive a copy of this document, indicate in the box C=Copy wlo atachment/enclosure

E=Copy with attachment/enclosure

N = No copy OFFICE l PECB lEELB EELB I El PECB I PECB l lDRPMl NAME s RJenkins JCalvo /1 RDennig SRichards

JRoel DATE 121249 I L,-,9l 212/t9 I / , I I,9 , / W OFFICIAL RECORD COPY}}

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