Some electrical comments

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kwired

Electron manager
Location
NE Nebraska
Yes I must be in a higher population density. 13 miles between subs is a long way. The longest main feeder is maybe 3 miles of 795 AL in the urban area. As we get out in the less populated area that distance increases. What is the name of your utility?
I was part of the Southern Company.

All electrical providers in state of Nebraska are publicly owned. Most are smaller companies serving relatively small areas compared to some of the big companies in other states that may serve an entire continental region. The systems serving cities will have shorter runs of line but the rural systems will serve pretty large areas at times. Electric irrigation wells is one of the bigger loads in the area in the summer - but rates are somewhat cheap in the winter because all the infrastructure is there to serve that irrigation load and it is not loaded anywhere near capacity in winter. This makes electric heating favorable for both the power supplier as well as the customer. The supplier needs extra load at that time of year because it costs to operate a system even when there is not much load on it, so lower rates encourages use of electric heating and it has been competetive cost wise with gas, or oil in the past.
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
120716-2121 EDT

bob:

There are probably 4 to 5 substations within a radius of 5 miles that could be tapped into, but there are apparently load problems everywhere. Tomorrow will be the hottest day of the year. Our primary is probably 4 kV and not 13 kV.

I believe our original load area following the fire was distributed over several of these substations.

Our burned out substation, I believe, was originally supplying our city airport, a large shopping center, two 15 story buildings, and various commercial, industrial, and residential customers.

Not real high density but a good size area extending over about 1/2 mile by 2 miles in an irregular shape.

At my home where voltage is normally about 123 to 125 we are running about 122 tonight. You can see my normal voltage at http://beta-a2.com/energy.html see figure 9.8.3.2 .

In the 5 mile radius area the University will have some large substations, but those would not be available.

.
 

hurk27

Senior Member
Being in close proximity to the center of my city if you want to call it that, my sub station that normally feeds my neighborhood is less then .5 miles from my house, to the east, to the west there is another sub that we can be automatically switched to that is less then a mile, then there is one to the north about .75 of a mile, and one to the south that is about 1.5 miles, all out sub feeds are loop feeds so routing is just a matter of control room switching, the feeds to the subs are 69kv and also loop fed from a major very large substation that is fed from the very large transmission lines from the power generating plants, then these can all be switched if one goes down at this main sub station to be powered from one of 5 generating plants, Michigan City 12 miles away NE, Wheatfield 16 miles south, Bailey's, 4 miles North, Dean Mitchell 12 miles NW, and State Line in whiting about 20 miles away WNW, so I guess we are covered, maybe because of the steel mills?

Where I live now we have never lost power for more then a few minutes, but when I was at the trailer park we lost power all the time from being on the end of a run.

Our local feeds are 12.47/7.2kv Y
Just look up Portage, In. on Google Earth and look around you will find small neighborhood sub stations all over the place. here is the one .5 miles east of me:
41? 34.333' N
87? 9.839' W
Then look straight west about 1.25 miles for another
 
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kwired

Electron manager
Location
NE Nebraska
120716-2121 EDT

bob:

There are probably 4 to 5 substations within a radius of 5 miles that could be tapped into, but there are apparently load problems everywhere. Tomorrow will be the hottest day of the year. Our primary is probably 4 kV and not 13 kV.

I believe our original load area following the fire was distributed over several of these substations.

Our burned out substation, I believe, was originally supplying our city airport, a large shopping center, two 15 story buildings, and various commercial, industrial, and residential customers.

Not real high density but a good size area extending over about 1/2 mile by 2 miles in an irregular shape.

At my home where voltage is normally about 123 to 125 we are running about 122 tonight. You can see my normal voltage at http://beta-a2.com/energy.html see figure 9.8.3.2 .

In the 5 mile radius area the University will have some large substations, but those would not be available.

.

Maybe not real high density but the load is there. The commercial and industrial loads are not as predictable as far as what kind of power demand there will be without knowing more about the establishments as the residential loads may be.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Write a thank-you note to Congress. Also thank the other customers for wanting cheaper power at the cost of reliability.
I see this all the time in every market -"blame the bargain-hunting customers". What about the merchants who offer up cheaper products with deficiencies and cut corners in order to wrest market share away from their competitors? It's not the customers who make the choice to sacrifice reliability or durability for lower cost, it's the vendors in our so-called free market system. Most customers only see the price tag without looking under the hood; they wouldn't understand what they would see there, anyway. Customers cannot be expected to be experts on everything they buy. This is why IMO total deregulation is such a bad idea; we human beings in the aggregate cannot be trusted to do the right thing. We have proven that to be true time and time again.

OK, off the soapbox... :D
 

kwired

Electron manager
Location
NE Nebraska
I see this all the time in every market -"blame the bargain-hunting customers". What about the merchants who offer up cheaper products with deficiencies and cut corners in order to wrest market share away from their competitors? It's not the customers who make the choice to sacrifice reliability or durability for lower cost, it's the vendors in our so-called free market system. Most customers only see the price tag without looking under the hood; they wouldn't understand what they would see there, anyway. Customers cannot be expected to be experts on everything they buy. This is why IMO total deregulation is such a bad idea; we human beings in the aggregate cannot be trusted to do the right thing. We have proven that to be true time and time again.

OK, off the soapbox... :D
As I mentioned earlier we have publicly owned electric utilities here. Their reliability is for the most part excellent. Mother nature has her way at times but otherwise excellent. Decisions of future need of energy are not profit driven like they are with private companies. They are always determining future generation needs and not sitting there running a plant hard because they didn't want to spend money on future generation until they have to.

Oops, not enough capacity, I guess we will have to demand customers to cut back on use and we will need to have rolling blackouts if the use does not decrease. Maybe we should have started construction of that new power plant sooner.
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
120722-2043 EDT Sunday

Update.

Last week voltage was running quite low during the day. Down to 105 without much internal load in the middle of the day. I set up my TED system to monitor and record voltage. During a 24 hour period there was a continuous gradual change in voltage from the low of 105 late mid afternoon to a high of 117 about 4 AM. No particular spike that we did not generate.

Yesterday late in the day I checked voltage and it was about 121 V. It was a hot day. Today also hot and I checked the three phases line to line at 247.4. 247.3, and 244.2. The 120 read 122.9.

DTE made a major change, and it probably was restoration of the substation. So this maybe was only 2 weeks and not 13 weeks to fix.

.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
As I mentioned earlier we have publicly owned electric utilities here. Their reliability is for the most part excellent. Mother nature has her way at times but otherwise excellent. Decisions of future need of energy are not profit driven like they are with private companies. They are always determining future generation needs and not sitting there running a plant hard because they didn't want to spend money on future generation until they have to.

Oops, not enough capacity, I guess we will have to demand customers to cut back on use and we will need to have rolling blackouts if the use does not decrease. Maybe we should have started construction of that new power plant sooner.

We have publicly owned utilities here, too. It's just that I have Consumers Energy and Gar has DTE. Since Gar lives on the east side of the state, he is getting the soiled end of the stick. Here in the west, we have higher standards and better services for less money.

:lol:
 

kwired

Electron manager
Location
NE Nebraska
They have been begging people to conserve energy and not use it if you don't need to lately. High temperatures are putting record demands on the system and there is a huge fire that has effected transmission reliability on top of that.

Of course all the wind energy sources that have popped up the past few years are not helping much because there has been little wind lately. I don't even want to go down that road.
 

mivey

Senior Member
DTE made a major change, and it probably was restoration of the substation. So this maybe was only 2 weeks and not 13 weeks to fix.
2 weeks is a pretty quick repair for major damage in a substation. Either the damage was minor or they were able to get some other temporary measures in place.

Just for curiosity's sake, you could ride by the substation to see if it is back on line...
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
120726-2227 EDT

mivey:

Drove by the substation. I have no way to know if it is operational by looking at it.

We have had different stories from different servicemen. My guess is that the substation is now back working providing three phases to us, of which we use two. This is simply defined by the voltages we see at the shop. Better balance now.

There appear to be two three phase transformers at the substation, and one large steel box with many doors. The newspaper photo seemed to show smoke coming from the top middle of the steel box.

From Google or Bing 2541 S. State St. Ann Arbor, MI may get you close. Also 42.249312, -83.734446 may be close. Presently I can not find out how to make Google or Bing give me the GPS location. Pictures are probably better today than a couple years ago, but functionality is worse. Dumbed down.

.
 
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