In the following snip from a previous exchange with Rick Cowles, he attempted to support his assertion that all areas of the power delivery system would experience Y2K failures that would reduce reliability of electric service. His response included an excellent but brief description of the power delivery system. I will try to use it to explain my personal belief that the Transmission and distribution portions will NOT put lights out, but continue to provide the level of service reliability historically provided under similar circumstances that excluded Y2K.

1. Which portion(s)/aspect(s) of the delivery system will be impacted?

Lets first define power delivery. Theres three major components to a typical regioinal power delivery system: generation, transmission, and distribution. Generation is the factory is where the power is produced. Transmission is the bulk product distribution pipeline. Distribution is the local (third tier; end user) end of the product distribution chain.

From a Y2k perspective, I expect disruptions in each of the three major components, somewhere in every geographic region on the planet. But lest you think Im less than forthright in this assessment, let me hasten to add that failures occur in each of the three major components of power delivery systems every day of the week. Each component of a typical power delivery system, though, has enough inherent redudancy that isolated failures are mostly transparent to the end user. The lights rarely go out, but when they do, its sometimes in a dramatic and totally unexpected fashion. (Ref: NYC blackouts, and the recent San Francisco blackout). More on this in a minute.

TRANSMISSION

The transmission system consists of transformers, substation bus work, high voltage circuit breakers, transmission lines/towers, and the control systems that protect and operate them.

The transmission grid is highly interconnected and power flows from generator to load is very interdependant and complex. HOWEVER, the protection and control schemes are not as interconnected and complex as the system they monitor and protect. The protection and controls solutions were designed in the 40's & 50's, and while the technology platforms have progressed, the approach has been to use new technology to emulate the original approach. This is the big myth of utility embedded chip fears, the protection and control system is typically NOT complex systems with high levels of integration.

The PRIMARY protection for transformers is a high speed electro-mechanical (E/M)device that monitors internal pressure of the transformer. These devices have no chips. Secondary transformer protection comes from differential protective relays. These were originally E/M relays that were connected to current transformers (no chips) on the high and low voltage sides of the power transformer. That is the extent of the interconnectedness, and the new microprocessor devices simply use digital algorithms to emulate the old approach. Single discreet device with no need for interaction with other devices to perform its protective mission. All brands and models of microprocessor devices were tested and found to have no fatal errors that would put lights out.

Protection of the Bus structure, Power Circuit Breakers, and Transmission lines are accomplished using discreet relays that are either E/M, or microprocessor based equivalents that replicate the E/M technology. The protective algorithms do not require the exchange of local data, and are not date dependant.

The dreaded embedded chip problems, and fear of hidden dates are real and valid when interconnected devices that have dates communicate them to devices that seem to have no date capability. These cases are very rare and almost non-existant in the transmission system.

DISTRIBUTION SYSTEM

Same story. Old design E/M solution are predominant. What microprocessor devices that do exist were designed to emulate the E/M approach. There is little or no interconnectedness, and the devices are discree, stand-alone devices.

Further down the distribution lines towards the customers, the protection is mostly E/M and thermal in nature. Little to worry about, but fuses do blow and require a service visit to repair.

I know this is disjointed and incoherent. Malcolm has done a much better job of describing in more detail the power delivery system. I guess my main point is that the proctection and control system are not highly integrated, interconnected, complex systems like you have been led to believe. the discreet devices have been tested discreetly. The rare devices that are interconnected were tested while connected. I believe all is well. I'm betting my career, my health and my family on it, not out of recklessness but out of confidence that the positive test results were thorough and accurate.

-- Anonymous, December 16, 1999

Answers

CL,

Thank you, I find your and some other utility engineers on this forum, if this doesn't sound too harsh, "belligerent optimism" a great counterbalance to some of my concerns. As I noted in an earlier thread, the only failures which I suspect would cause more than inconveinence would be process control areas as you have outlined above, not the type of book-keeping failures which we have already sparodically observed. Taking as truth that you have zero process control failures in areas under your control, I might still be a Nervous Nellie and advise moderate, reasonable preparation. Howard Rubin, in recent Senate testimony was one who emphasized two points, 1) his concern about interfaces and 2) there could be failures despite 100% remediation because of changes in behavior brought about from uncertainty. An example which might apply to your situation. It has been stated that most major railroads and more importantly many local metro transit systems will shut down over the roll-over. While all of your internal interfaces may interact beautifully, there will be definite load fluctations at this time. The transit authories are joined in shutting down temporarily for the roll-over by a number of chemical factories and unknown (by myself that is) number of other heavy industries. Concurrent with this, will be the large number of planned extragavent millenia galas. I will be preparedly optimistic with you, but even if there is not a single Y2K failure anywhere, there is a decent chance there will be demand patterns placed upon electrical grids that have never been encountered before. I realize I am taking a skeptical stance but I hope it is for a good cause, here's hoping this storm blows out to sea.

God Bless,

-- Anonymous, December 17, 1999

Thanks CL, FYI, from the EPRI database, I reviewed a number of protective relaying devices manufacturers information, and found none that failed for y2k, although a few did have date stamping problems. Do you know of any more serious y2k bugs?

Regards,

-- Anonymous, December 17, 1999