Aging Infrastructures for the Utility, Condition monitoring & assessment: General Thoughts

[snerts50]

I have been tasked yet again to try and poll my peers about a topic, Aging Infrastructures Condition monitoring & assessment for the Utility.

Anyone on this forum actively part of a Utility program for monitoring their equipment for replacement? Any general comments on how well that works, what could be done better, etc? Is there some new, interesting method or technology on the horizon for condition monitoring?

Is anyone aware of some form of active equipment condition monitoring? I know of SEL relays which can measure the contact wear of a breaker, but not much else. Is there a device that actively measures the condition of a station transformer, for instance. I would assume pressure and temperature, sure, but any condition monitoring where some alarm could be triggered for either a more in depth condition assessment, or replacement.

I was reading some articles when generalized the subject. Some thoughts were, to focus on critical areas for rigorously, since lets say the loss of that feeder's equipment could leave thousands without power, or hospitals or something like that.

And that it is Condition that matters, not age. Just because something is old does not mean its in poor condition, and in fact actually proves that the Utility got their monies worth.

Is it possible to have a condition assessment program, active or not, that has false positives? I would assume this is always the case, and sometimes the Utility is replacing equipment that is still in fine condition.

 

[cranky108]

Why is it that the public wants everything new, but they have no desire to pay for it?

Most of the invester owned, and public power is very well managed for age and condition. If the life of equipment was one year, than most utilities will replace the equipment every year. However, most utility equipment has a life that exceeds 30 years, and that is the time that the equipment is expected to last, or it's life is extended to last longer.

Reliability at most utilities exceeds 99.9%, and people want better than are not willing to pay for it, which is just dumb. These people can freeze in the dark for one hour a month for all I care.

 

[MikeHalloran]

Speaking as a civilian who owns a small fraction of an acre of aging infrastructure and has been fighting the aging forces for a while:

The problem with monitoring equipment is that it ages at the same rate as the monitored equipment, so becomes less likely to properly detect and alarm a problem as the likelihood of the problem's emergence becomes nontrivial.


WRT utility management, it is here very well managed, for the benefit of the shareholders, as distinct from the customers.
When we arrived in SoFla in 1978, we noticed that a crew of tree trimmers came around twice a year to trim the foliage from under the overhead lines, at no direct cost to the homeowner, paid by the utilities as a prophylactic measure.
Then FP&L went after the Deming Prize For Power Outages.
Thereafter, the tree trimmers came around only after major storms, paid for by the Federal government in response to the unforeseen circumstance of power outages caused by wet trees rubbing on power lines.

Now some idiots are campaigning to put the power lines under the surface of the perpetually soggy ground here. Personally, I'd rather have the arc light show up in the sky, where I can see and hear it (it's damn impressive), rather than somewhere beneath my feet. ... but that's another discussion.





Mike Halloran
Pembroke Pines, FL, USA

 

[snerts50]

cranky,

Thanks for the reply. So you think that Utilities are pretty good, typically, at replacing aging equipment and maintaining reliability. I don't have a lot of information to back that up, but I would agree, otherwise the regulatory bodies of those utilities would be all over them. I would also think that not only does the Public not want to pay for it, but neither does the Utility, right? They want to get as much bang for their buck as possible, keep everything energized for it's entire lifespan. Are you an active part in replacing Aging Infrastructure at a Utility?

Mike,

Thanks for the reply. I see your point, and it's a good one, what use is the monitoring equipment if that equipment also ages and deteriorates. How can you trust its accuracy? What monitors the monitoring equipment? So it also seems like your local Utility was more proactive a few years ago, when it was owned by WRT. Now that FP&L owns it, they are more reactionary. So it seems like there was a change in process as to how they go about replacements.

Thanks again for this.

Seems like it might make more sense to have more active manned monitoring programs based on ciritcality and such, rather than automatic equipment based active monitoring.

Any one else have any thoughts? Seems like Utilities needs ways to Identify and "score" conditions of equipment to gauge what should be replaced when.

Caleb

 

[PeterVenkman]

Transmission level utilties often have agreements for maintaining a certain level of reliability with their distribution customers (outage hours a year) and don't make addition investments unless they are exceeding these agreements. The only investments that I know of in the industry that are not justified for reliability reasons are upgrades tied to smart grid but are government subsidized. As I have seen, utilities usually do a very good job at maintaining high reliability at very low cost.

As a side note, there is some transmission in Kansas that is over 100 years old. I think it is part of Westar's system.

 

[snerts50]

Anthony I appreciate the response.

It seems like the general feel is that Utilites do fine in terms of reliability, for the most part, only spending what they need to to maintain equipment. And it seems like, in some instances, this is enough. i am sure it isnt in other cases.

 

[WantToBeAnEE]

snerts50, I think the belief that utilities are doing fine in terms of maintaining equipment is a bit naive. In some cases it is probably true, but in many I think it is false. There is the large difference between the maintenance of mechanical equipment (circuit reclosers, transformers, regulators) and non-mechanical equipment (such as poles and wire).

In my opinion, the typical utility's systems are not quite at the point where the lines and poles are going to fail from being unmaintained. For example, the electric cooperatives in the US only started building lines in the late 1930's and early 1940's. Many of the poles that were installed in that time are still standing (barely). Until those poles reach a point where they begin to fail in large quantities I don't think the general public will notice the deterioration. Many companies test poles about every 10 years or so which identifies the ones that will fail soon. Some companies don't even do that though. One way to monitor the non-mechanical infrastructure is through a Geographic Information System (GIS). Using GIS a utility can track the age of every piece of equipment on their system and can identify equipment that may be at it's end of life to create a maintenance plan.

When you get into mechanical equipment it is a little tougher. One way that the utility I work for monitors equipment is by infrared testing. We annually go around our system and look for overheating of equipment which can alert you to potential issues. Though, this is a time and labor intensive task and can only be done cost effectively on a small amount of equipment. In addition to that we also cycle our circuit reclosers through a 3 year maintenance cycle to keep them operating efficiently.

So, it's not a very proactive plan and there is a lot of room for improvement, but that is what we do. In general it's a very reactive maintenance plan where if something fails we begin to look into replacement of all the equipment that is that age or type. Hope that helps a little!

 

[snerts50]

WantToBeAnEE, thanks for the response, I was hoping for some insight from another utility. This was great info.

I appreciate everyone's help on here, great stuff!

 

[cranky108]

Yes I am involved in replacing aging utility equipment, or more to designing the replacments. I have worked for three types of electric utilities, and can honestly say that electric cooperativies don't do as good a job as invester owned, or muni's. The problem is the method they have to approch to borrow money from DC, and the rules they have to follow in the construction. I have seen that the requirments for poles were underclassed and the invester owned in the same area had much less storm damage.

The other problems are the attitudes of the people running the utilities. Muni's have techinical people running the utilities. Invested owned had accountants running the utilities. And cooperitives had old linemen running the utilities. The difference is how each of these groups approches trees, and outages.

On the other side is the regulating people who are at worst a bunch of political hacks, some are accountants, and some are techinical people. Then you have the people most likely to influense the regulating people, and again political hacks, university know it alls, and enviromentlists.

So to say the industry is perfect, is a lie, but given the job to be done, the utilities do a good job. Unless you live in an area where the utility is trying to reduce rates at the expencise of outages (a managment problem).