Spare the fuse, spoil the food


The Traffic Signs (or lack of) of Trouble

Continental MHP was hit with a string of power failures just when the heat was at it's highest.  It all started on Friday afternoon, July 21, 2006.  I noticed as I came up Tennyson Road, a series of traffic lights were in "blinking mode" meaning the traffic system just lost city power and were running on standby power.  All of the Continental MHP at the same time was without power.  Fine, it was probably one of those "rolling blackouts" and nothing to worry about, PG&E will get the power back in an hour or two.  In the meantime, I'll stay out of the refrigerator till the power comes back again.  In a few hours the power did come back on.  Later, I noticed more lights further up the street also went out, time for their rolling blackout.  We now have power back on.

Hottest day of the Year

Saturday afternoon must have been the hottest day ever, I heard a lady shout nearby "Oh my God, it's 110 degrees out here."  Sure enough,  I read 110 degrees in the shade on my outdoor thermometer.


Outdoor Temperature Reading

So what did I do on the hottest day of the year? I was up on the roof of my mobile home all day fixing my Swamp Cooler while my daughter was trying to fry an egg on the street pavement as a science experiment.  Something I recommend not doing, including trying to fry the egg.  Totally exhausted and wiped out by the heat, I decided to take it easy and watch some TV with a cool soda.  At 5:47 PM the TV went out along with everything else.  Oh no another Rolling Blackout!  I went outside to check out the scene and noticed the lights were on at the Clubhouse.  It was no rolling blackout, power was lost in parts of the Park.  Some people started to walk over toward the Clubhouse, including myself, where Glenn, the Park Manager, was standing.  Glenn stated that PG&E was contacted and the earliest time they could arrive would be 5 to 7 AM the following day.  That's a dreadfully long time!  Glenn also told us that our own Park Electrician (Comco Electric) was contacted and he would be here as soon as he could.  At about 2:30 AM the following day, now Sunday,  I heard the backup beeper of the PG&E truck.  Being so hot and stuffy, (no fan) I was wide awake so I got up and watched the the PG&E guy.  He checked out the switch gear and was gone in 10 minutes.  Well that's just great, we still don't have power and were is Comco Electric?  He should have been here hours ago (located in Pleasenton, I am told).  At about 3:30 AM Comco shows up.  But only for a few minutes, he takes off without any power being restored.

The Cat Comes Back

I now give up any hope of getting power back to my refrigerator, I haven't opened it yet and now start to dread what will happen to all my food.  My wife just loaded up the fridge with fresh food Friday, including goodies from Trader Joe's.  At about 6:30 AM, I hear a truck arriving.  It's that Comco guy again.  This time he's holding the biggest fuse I have ever seen!  After installing the fuse, the power comes on.  Finally after 13+ hours we have power!

So I go outside and talk to the Comco Guy and asked him why it took so long to restore the power.  He told me that a 400 Amp fuse had blown and none were in his truck.  He told me that spares were locked in a warehouse with an alarm system limiting access time after 9PM.  A 12 hour or so response time is crazy!  He could have picked up that fuse if he came down after we called, well before 9 PM..  After all a fuse is probably the most common of faults during hot weather.  Everyone with an air conditioner will turn it on to escape the heat.  In fact, that's the reason he gave me why the power went out. Too many air conditioners!

Now I remember years ago when I was a young kid, my dad would keep spare fuses in the fuse box.  Remember those plug fuses that screwed in like a light bulb?  They were called Edison style fuses,  invented by Thomas Edison.  Wouldn't it have been a good idea to keep a few spares at the Park?  After continuing to talk with the Comco guy, he told me that he had only one more left.

Surveying the Damage

The sun is rising from the east and it don't look good. Another hot day it's going to be!  I start running my fans early in the morning (now sunday) to flush out the warm, stale air from a sleepless and powerless night.  Now for the first time after losing power my wife and I inspect the food in the fridge. It doesn't look good, the ice cream is soft, the sodas are not very cold.  I quickly insert a thermometer and wait a little longer for the temperature to stabilize.  I check the temperature, 65 degrees in the lower compartment, too warm to trust food safety.  Much of the frozen food is already thawed or significantly thawed.  Juices were completely thawed, ice cream was cream soup.  One by one my wife tells me what stays and what goes.  I trust her decision on what is good and what is not.  I proceed to record with the camera what was tossed in the can.  I fact, I didn't have enough room in my trash can to hold all the stuff.

 
       

   

 
Food that had to be tossed out
It happened again !
It's Sunday and the refrigerator is slowly cooling down and the fans are keeping the temperature down a bit.  It's still hot, about 100 degrees inside the house. Wouldn't you know, that fuse blows again at 1:30 PM in the afternoon.  The refrigerator never gets a good chance to cool down.  Once again PG&E  and Comco Electric gets called and once again PG&E tells us it the Park's problem.  The Comco Guy doesn't get here till 10:45 PM and installs that last fuse he has.  This time it was out 9 hours, still a long time to get things going again.  Glenn tells me his excuse for not getting here earlier is he has many other calls to attend.  What is this Comco Electric, a one man operation? He's used the last fuse, what if it blows again?

and again !

Another hot day and once again the fuse blows.  The power outage lasted from 5:15PM to 8:30PM. This time Comco arrived in 3 hrs and replaced the fuse.  This time he had spare fuses ready.  So far it seems the plan is just to change fuses instead of getting down to solve the root problem.

What is the real problem?
Is the problem really too many air conditioners?  I talked with other residents at the park that have been here a long time.  These residents do not recall having so many outages for so long.  On July 25, we all were sent notices telling us the problem was too many appliances and air conditioners running.  Telling us we should set our thermostats to 85 degrees and limit use of appliances and microwave ovens in the afternoon.  Even PG&E recommends setting the thermostat to 78 and not 85.

The Park Association President, Tony Froncek sent us all a Park Complaint Form (here and here) to fill out and present to the owner for our loss of food costs.

So this got me thinking, just how much power is available to park residents.  We have almost 200 units at the park.  When the power went out, 80% of the park went out.  This leaves about 160 units that have to depend on that fuse.  I started to figure out what power is available.  Power is brought in from PG&E at a high voltage (7500 volts) and stepped down to 480 volts.  The fuse that blew was in series with this 480 volts and is distributed as a 3-phase system with other distubution transformers (100KW each) scattered in the park.  These transformers step down the voltage to the 240/120 that connects to the homes at the pedestals (power box to the home). Some of us noticed we were still getting a little bit of power.  I measured 15 volts with a meter.  This voltage is due to the difference left from the two remaining phases.

The math to calculate power in watts:

480(volts) X 400(amps) X 1.73(factor for 3 phase circuits) =  332 Kilowatts  That's 332,000 watts

Because some loss due to power factor and transformer inefficiency,  real power is probably about 5 % less.  Leaving us 315 kilowatts for the entire park.  This includes the clubhouse and the units that had power.  Not knowing how much power was used for those who had it makes it difficult to calculate what's left.  As a rough guess lets say 80%

.80 X 315 kilowatt equals 252 kilowatts

Divide this by 160 units we then have only 1,575 watts per unit or 13.1 amps at 120 vac.  Gosh, that not very much.  If everyone started their microwave ovens at the same time, another blown fuse.

I don't know everything about our electrical system, this is based on my own observation.  Feel free to correct me if I'm wrong on any of my assumptions.  But I do believe we are under-powered.

                        
   All the power for the Park from PG&E comes here.                                High Voltage (1 of 3 xfmr's)                 100KW Distribution Transformer



It's 9 pm, do you know were your fuses are?

So what can we do?  Not much unless we upgrade the system.  This would include new and greater capacity switch gear.  You can't just add more breakers or bigger fuses and more distribution transformers on a overloaded fuse.  The owner is already replacing the underground wiring, meters and pedestals at a cost of up to 1 million, which he says he will pay himself.  This alone does not increase capacity.  Presently the only plan I see is "get more fuses"  Our system needs to be monitored and analyzed. There might be a different problem happening now that can be attended to without great costs.  It is assumed that it's "too many Air Conditioners" and it's our fault.

Some ideas to keep cool and prevent blackouts:

1.  Limit air conditioner and appliance usage during peak hours (between 3 and 8 pm)  Save that washer or vacuum for the evening.
2.  Precool your home early in the morning with your swamp cooler so it takes longer to heat up.
3.  Use a swamp cooler or fan instead of a air conditioner.
4.  Keep the thermostat at 85 or more.
5.  Use compact fluorescent lamps instead of regular light bulbs ( they really work to save electricity!)
6.  Go out to the Mall and enjoy their air conditioner.
7.  Keep Ice packs ready to keep medications cool during blackouts.
8.  Have emergency numbers ready.
9.  During heat waves, limit food in the fridge so there's less to throw away during those long outages.
10.  I keep a Misty Mate handy and spray down once and a while.

What Management can do:

1.  Keep spare fuses already at the park instead of some locked warehouse.
2.  Have an alternate and more local electric company to change the fuse ready.  Keep a credit card just for services payment.
3.  Always have someone ready to call in emergencies.
4.  Encourage outdoor activity.  If your outdoors, your not using electricity.


We can try this:

Remember the TV show Green Acres? and how Lisa had to limit her power usage by assigning each electrical item a number?

Episode 9  "You can't plug in a 2 and a 6"  First aired 11-10-65 


   Lisa made this list to prevent fuse blowing.




Conclusion

Now that we are aware that the Park can become blacked-out if our power system becomes stressed. We can improve our situation by use of common sense when using appliances during hot weather.   I know we didn’t buy air conditioners to set the thermostats to 85 or above. Lets save ourselves the burden of another blackout by reducing their usage.  Maybe there is a way we can live with a low capacity system.

Last updated 8-4-06

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Links:

http://www.allaboutcircuits.com/vol_2/chpt_10/5.html

http://science.howstuffworks.com/power3.htm