All OK for Y2K?

In the March 1998 issue, PEI took an initial look at the Year 2000 problem and how it could affect the power industry. In the second of this series of articles in the run up to January 1, 2000, PEI presents some key findings of an NERC report to the US Department of Energy on the US industry readiness for Y2K.

In a letter to the North American Electric Reliability Council (NERC), the US Department of Energy (DOE) requested an initial assessment by September 1998 of the US electric industry`s progress in addressing the Y2K bug. The assessment was to look at all aspects of electricity production, transmission and distribution. The report is the first in a series which will be published on a quarterly basis to measure progress compared to this initial benchmark report and the goals defined in this report.

The assessment covers six sections of the industry: nuclear power generation; non-nuclear power generation; energy management/Scada systems; telecommunications; substation controls and system protection (including distribution); and business information systems. This article presents the key findings and recommendations related to generation.

The NERC Y2K Readiness Assessment process used a detailed questionnaire, aimed at 200 bulk electric operating entities, which allowed each organization to report Y2K project progress across NERC-established mission critical areas. The reporting cycle was initially completed in July 1998, with 95 bulk electric entities reporting. The questionnaire was revised and reapplied in August and 144 organizations responded. Overall more than 75 per cent of the organizations participated in the assessment.

Reports were received from entities representing: 603 056 MW (84 per cent) of system peak load; 551 658 MW (77 per cent) of non-nuclear generating capacity; and 81 965 MW (74 per cent) of nuclear generating capacity.

Non-nuclear generation

Findings: Figure 1 shows the findings for the non-nuclear generation. It shows that currently 89 per cent have completed the inventory phase of the Y2K programme; 61 per cent have completed the assessment phase; while 26 per cent have completed remediation/testing. Figure 2 shows the current projection for mission critical non-nuclear generation facilities becoming Y2K ready.

Analysis: A reliable supply of generation is essential to minimizing the operational impacts of Y2K. One issue is adequacy of supply (having enough generation on-line or ready to be synchronized to meet demand plus reserve requirements during critical Y2K periods). Another issue is that generating unit forced outages due to Y2K problems could result in power system instability, voltage collapse, overloading of transmission systems, or capacity shortages.

The progress and expected completion dates for the readiness of generating facilities are fairly consistent with the overall Y2K progress (across all industries). Consequently, there is a need to modify schedules at some organizations to meet the target of having generating facilities Y2K ready by June 30, 1999.

Like the other technical areas, Y2K anomalies are being found in only a very small percentage of components and systems. Generally, less than one to two per cent of inventoried items failed initial tests. There also appeared to be a great degree of diversity of components among vendors and even within a single vendor`s product line. This diversity reduces the potential for common mode failures among units.

At the same time, however, generating units are complex and vary substantially in their use of computers and digital controls. Many older stations are operated principally with analogue controls and face very little risk of Y2K anomalies internal to the station. Other more modern stations with digital control systems (DCS) may require extensive preparations. Working closely with vendors of these DCS` is critical to identifying and correcting Y2K problems.

Power plants are operated and monitored by capable and experienced operators and technicians. In many circumstances they can respond to problems and adjust operations manually to maintain reliable unit output. One concern, however, is that there may be less ability to manually operate units that use modern DCS controls, which are very complex and fully automated.

One issue in preparing generating units to be Y2K ready is the extent and nature of the testing required. It is common to bench test individual circuit boards, controllers, and software applications within the plant. When systems are tested in an increasingly integrated manner, Y2K risks can be effectively reduced.

The ultimate test for a generating unit is to conduct a series of Y2K tests for the entire unit – an “on-line” test. This type of testing can be intrusive to operations and costly, and is as yet of uncertain value. Several organizations plan to conduct such on-line tests during the autumn of 1998. In some cases, these tests will be conducted under live operating conditions set up to stimulate the transition into the Year 2000. The tests are being conducted during an off-peak season to limit the impact of losing operational availability. The results will be published in the Fourth Quarter 1998 NERC Y2K Readiness Report to the DOE.

Initial test experience shows that strategies other than repairing or replacing all deficient equipment may sometimes be appropriate. For example, electronic clocks can be advanced to the Year 2000 during testing and left in that mode once it is determined that no problems occur. Another alternative is to set clocks to an earlier date to avoid the roll-over to the Year 2000 altogether. Both methods have been demonstrated to work in some cases.

Fuel supply is a critical part of the power production chain and needs to be considered. The Federal Energy Regulatory Commission is coordinating a similar effort to NERC`s in the natural gas industry to assure the readiness of natural gas supply systems. Coal and oil delivery systems are equally important and Y2K efforts in the electric industry must be closely coordinated with these related systems.

Recommendations: Generators should adjust Y2K readiness schedules and resources to meet the recommended milestone schedule.

Organizations with DCS controls on generating units should work closely with vendors to address Y2K issues.

NERC should facilitate an industry assessment of the benefits and risks of on-line generating unit tests and propose guidelines by the end of 1998. The Electric Power Supply Association (EPSA) should assist NERC in coordinating Y2K efforts with independent power producers.

Nuclear generation

Nuclear generation is an important part of the electric supply mix and is addressed as a separate element in the report.

Within electricity production and electricity delivery organizations, nuclear facility Y2K programmes are closely coordinated within the overall enterprise-wide Y2K programme. An assessment of Y2K carried out by the Nuclear Energy Institute (NEI) was incorporated into the NERC report.

Findings: Over a year ago, the nuclear utility sector began a coordinated effort to identify and resolve Y2K issues. In October 1997, NEI published the Nuclear Utility Year 2000 Readiness Guide, NEI/NUSMG 97-07. This is a six-part guide which is in use at all nuclear generating facilities providing operators with systematic, detailed procedures and checklists for solving Y2K issues.

The nuclear industry`s efforts are supported by a number of existing organizations, with NEI providing overall policy organization. The Nuclear Utilities Software Management Group (NUSMG) provides technical expertise and conducts project manager training. Most facilities also participate in EPRI`s embedded systems programme.

Through the NEI, the industry`s Y2K efforts are closely coordinated with the Nuclear Regulatory Commission (NRC) to ensure public health and safety issues are addressed.

According to the report, no nuclear plant has found a Y2K problem in safety systems that would have prevented safe plant shutdown at the turn of the century. This confirms a September 1997 NRC staff policy paper that concluded: “safety-related initiation and actuation systems (e.g. reactor trip systems, engineered safety feature actuation systems) are not subject to the Year 2000 concern”.

Nuclear Y2K readiness programmes have focused on management and tracking at the component level. Thus nuclear generation status reports have been based on component level readiness. By February 1998 all nuclear generating facilities reported that they had implemented detailed Y2K readiness programmes that were consistent with industry guidance.

In February, the initial inventory was, on average 50 per cent complete. Today, the initial inventory is essentially complete. The schedule for anticipated completion of detailed assessment is shown in Table 1.

Analysis: The nuclear industry is finding that statistical analysis alone is not providing a reliable picture of the level of effort or status of individual programmes. Relatively few digital components have been identified as having Year 2000 deficiencies. Those that are found are quickly remediated. At each facility there are a few components that are challenging to test or require extensive and costly remediation programmes. Thus a small percentage of the items drive most of the effort.

Based on the programme established a year ago, nuclear generating facilities are on schedule to achieve Y2K ready status. Current efforts are focused on completing testing of susceptible components, remediating identified Y2K problems, and developing contingency plans.

Recommendations: Managers of nuclear generation facilities should continue to coordinate Y2K efforts among themselves through industry associations such as NEI, and in cooperation with the NERC Y2K readiness assessment process.

Managers of nuclear generation facilities should continue to apply necessary resources to meet the stated schedule.

What`s ahead

The survey concludes that organizations that have largely completed testing indicate Y2K may not have a large impact on electric power systems. Electric systems consist mainly of wires and metal devices and do not rely heavily on digital controls. Testing of computer systems and control devices, according to the report, have turned up very few date-interpretation problems.

However, it states that much more work remains to be done, if all companies are to meet or exceed the target date for Y2K readiness (May 31, 1999) set in the report. The electric industry must accelerate efforts to resolve all Y2K issues within the next eight months. Meeting this target will allow the industry to focus on unexpected problems and final tests before January 1, 2000.

The industry has already begun preparing for worst-case scenarios and contingency plans in the event of unexpected system impacts of the date change. The goal and expectation is that electric systems will be able to sustain reliable operations through critical Y2K transition periods.

The report also covers energy management systems/Scada; telecommunications; substation controls and system protection (including distribution); and business information systems. It is worth noting that most of these technologies are much more computer/communications dependent; and in the case of telecommunications could be at greater risk since they are more dependent on external service providers. The findings regarding these systems will be published in PEI at a later date.

Further information

Preparing the Electric Power Systems of North America for Transition to the Year 2000 – a status report and work plan (Final September 17, 1998). Prepared for the United States Department of Energy by the North American Electric Reliability Council.

On the Web

The Y2K Problem

The Y2K bug results from a programming convention for the designation of a date as MMDDYY in the USA and DDMMYY in other parts of the world. This convention has been widely used since the earliest days of computer programming and now affects numerous software programmes and electronic devices including some of those used in electric power systems.

The common belief is that the problem came about when programmers, trying to save precious and expensive memory space, adopted the use of two digits for the year. Another explanation is that programmers were simply carrying forward a common practice in everyday life of depicting a date as DDMMYY. Because most computer applications (then as well as today) are not date sensitive, programmers were simply denoting a date in the same manner it would be viewed or written by a human.

The bug becomes apparent in the transition from the year 1999 to 2000. The most obvious outcome is that computer programmes and electronic devices could interpret 1/1/2000 as 1/1/1900, causing problems for any applications that depend on time or dates. Testing has shown that the Y2K bug is actually more complex than this simple explanation because a variety of problems can occur with date interpretation.

The problems are not restricted to a single date change at midnight December 31, 1999. Date related anomalies may occur at 1/1/99, 9/9/99, 2/29/99 and up to a dozen other dates. August 22, 1999 for example, has been identified as a date when clocks may expire in Global Positioning Satellites used to provide time signals to some electric power control centres. Although there are many types of Y2K failures, the three dominant ones are:

Y Failure to recognize the correct year in the transition from 99 to 00

Y Expiration of an electronic OclockO that was referenced to measure time as the number of seconds from an initial start date, such as January 1, 1970, and which will expire on a certain date when the counter runs out

Y Use of certain values, such as 99, to serve as placeholders with special meanings for programmers, hence the concerns for 1/1/99 and 9/9/99.

Fortunately from an electric reliability perspective, New Year?s Eve falls on Friday December 31, 1999 and January 1 is a Saturday. Because demands on the electric system are lower at night and on weekends, there is likely to be excess generating capacity available during the most critical Y2K period.

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