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Old 2017-10-16, 02:30   #122
LaurV
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Quote:
Originally Posted by only_human View Post
Elon Musk is proposing his technology for Puerto Rico:
Twitter:

Elon Musk’s offer to rebuild Puerto Rico’s electricity grid is a game-changer
Aie aie aie aie aie aie Puerto Rico...
Wake up Angelita, your mama just turned OFF the light...

Hehe...
Premonition?

Last fiddled with by LaurV on 2017-10-16 at 02:33
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Old 2017-10-18, 00:14   #123
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I'm in Puerto Rico helping restore the communications network. I've been over much of the east end of the island over the last 5 days. There are several huge solar arrays in the southeast near Guayama and numerous office buildings and businesses in the area around San Juan, Bayamon, Santurce, and Rio Piedras that have solar panels on the roof. I don't think solar power is much of a surprise to most Puerto Ricans. The southeast solar arrays are in serious disarray. I saw about 5 acres of them blown and strewn across the landscape and numerous damaged panels in the remaining arrays.

What would be new would be a commitment to convert most of the power supply on the island to renewables. This would be very difficult to do with solar alone. Puerto Rico has numerous areas ideal for both onshore and offshore wind farms. If an investment were made in a combination of solar and wind power, Puerto Rico could fairly easily transition from fossil fuel to renewable sources of electricity. There are a bit over 3.4 million people on the island occupying about a million homes plus about 300,000 businesses. About 3 gigawatts of generating capacity would meet most of the needs of the island. This would require in the neighborhood of 1000 wind generators at 2 megawatts each plus about 3000 acres of solar panels at 1 megawatt per 3 acres.

The devastation is almost beyond description. There is a microwave tower in Guayama that looks like twisted up pretzel sticks. The top of the tower hit the phone office hard enough to knock a hole in the roof. Fortunately, there is one antenna now lying on the roof of the phone office that is still working. That antenna is all that permits cell phone calls to be made in the area. Street signs were not exactly prominent before the hurricane. They are mostly missing now. They were blown off the posts by the wind. Many of the posts are missing too with a jagged stump sticking out of the ground or just a hole in the ground with no sign of a post. Power lines and communications cables are lying on the ground for miles at a time. On the southeast coast, houses are blown away leaving toothpicks and shattered walls.

It is common to see lines of cars pulled over on the side of major roads near cell towers. It is just people stopping to make phone calls. They drive out of the mountains to get to a location with a signal.

On a positive note, electricity is starting to be restored. We see power crews working daily. Trash trucks are picking up loads of debris and hauling it away. Traffic has picked up to the point daily traffic jams have to be navigated.

What am I personally doing? I help restore service to the land line phone offices. There have been a number of challenges. One office has a generator that is not up to the task of supporting all of the equipment plus lights and air conditioners. The problem is that so many of the outside cables are shorted out that they are drawing more current than normal. This causes the line equipment in the office to heat up which triggers the air conditioning to run much more than normal. The load is more than the generator can supply therefore the batteries gradually discharge until the phone office goes down from low voltage. We have the office back inservice. Most of the equipment has a hot standby unit that is out of service to reduce power consumption. Some unneeded equipment will be decommissioned over the next week which will allow the remainder to be restored to service. I visit 2 to 4 phone offices per day and do what I can to help.
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Old 2017-10-18, 08:10   #124
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Quote:
Originally Posted by Fusion_power View Post
I'm in Puerto Rico helping restore the communications network.
That's vital work - hope it goes well!
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Old 2017-10-25, 07:45   #125
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I am back home tonight after spending 12 days working on phone offices trying to repair defective equipment with insufficient spares. There were several huge challenges. A massive generator in Bayamon failed Sunday forcing the local supervisor to order shutdown of three phone offices in the building it served. This included a large tandem switch serving traffic to the entire island. The team I worked with got messages asking for help about 2:00 pm. We drove to the building at 4:00 pm but could not help because the emergency generator was not yet connected. There is a really weird feeling walking through a blacked out building with flashlights as the only light source. We left our phone numbers with the switch technician so he could message us as soon as power was restored. He texted me about 8:30 pm and we were back at site by 9:00. We worked 6 hours restoring partial service until we were too tired to continue. I had a flight home the next day at 1:00 pm. Two other techs returned the next morning and restored service to most of the remaining equipment finishing late Tuesday night.

There are memories of the form "I'm getting too old to do this stuff and I can't remember things I used to know and do 20+ years ago.
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Old 2017-10-25, 20:38   #126
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I salute you for taking on such a job! Restoring communications corrects a vital need for recovery (amongst many vital needs, of course.)

Any thoughts on FEMA activities?
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Old 2017-10-25, 21:30   #127
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Fema rented several dozen rooms in the Sheraton convention hotel. I briefly spoke with several truck drivers, administrators, and others as they went about daily activities associated with distributing fuel, food, and water across the island. I can't say if they were highly effective in their work because I was to busy doing things where I could help. I can state that there was marked improvement over the 2 weeks I stayed. There was lots of cleanup of debris on the sides of roads, houses were tidied up, and businesses were re-opened. By the time I left, there was a lot more traffic on the roads to the point that traffic jams were a daily occurrence. I was surprised how well drivers adapted to having zero working stoplights. Cars went through intersections in groups from 2 to 5 for the most part. Traffic cops were put in place at heavily used intersections.

How well has the media done portraying the damage? They have IMO done a lousy job. They overstated the impact of the hurricane in some areas, understated the difficulties in clearing roads and distributing supplies, and drastically understated the amount of damage. I drove just about all over the east end of island. Some areas had 100% of power lines and phone cables laying on the ground in broken segments, many times covered with trees and debris up to 20 feet deep. Houses for the most part survived because most were built from poured concrete. This type construction is particularly good to withstand hurricanes. Contents of the houses are another story. One person told of leather furniture turning green because of the heat and humidity. Air conditioners, refrigerators, and freezers are useless unless a generator is available to power them.

I have pictures of a cell phone tower twisted and bent over on top of a phone office roof in Guayama and of cables elsewhere dangling just a few feet above passing traffic. Pictures can't adequately describe the wholesale devastation on the east and southeast of the island. Solar panels strewn about like so many dominos after being toppled, a phone office still an inch deep in water after a hole was ripped in the roof letting water in to inundate the equipment, rows of palm trees laid on the ground with coconuts strewn and a few still hanging from pedicels, and other memories of similar devastation are a few things I saw.

My best estimate of the dollar cost? I can only hazard a wild guess of about $150 billion. It is probably too low. Unemployment is overwhelming with many jobs wiped out by the storm. Cleanup jobs are abundant but generally low paying. It will take years for ordinary people to recover.
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Old 2017-10-26, 00:28   #128
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Quote:
Originally Posted by Fusion_power View Post
I have pictures of a cell phone tower twisted and bent over on top of a phone office roof in Guayama and of cables elsewhere dangling just a few feet above passing traffic. Pictures can't adequately describe the wholesale devastation on the east and southeast of the island.
Mother nature is a harsh mistress.

Like kladner, I commend you for the work you, and many others, did.

Do you have any thoughts about what should be done for expedient restoration of telephony service after a storm?

I spent four hours in a meeting today with people who didn't know what they were talking about saying everything should be underground.
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Old 2017-10-26, 14:21   #129
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Here are pics to show the destructive power of a hurricane.

http://www.selectedplants.com/miscan/cables.jpg
http://www.selectedplants.com/miscan/celltower.jpg

Chalsall, I took several notes of things to do that would have prevented this level of destruction. Burying cables is only one part of the problem although I agree that buried cables would have saved key parts of the network on Puerto Rico. Here are some thoughts that you are welcome to share.

Generators will have to maintain communications infrastructure for about 3 months in most centers. Generators are subject to failure and are not redundant - meaning when one goes out that center is off the air. Battery backup systems will buy you about 8 hours to deal with a failed generator. Do NOT rely on battery backup for anything except that critical 8 hours! These generators started running out of fuel within 24 hours of power grid failure. Serious consideration should be given to providing an available fuel supply that will last a minimum of a week, having backup supplies to last another 3 weeks, and having backup generators with connectors ready to plug in if one fails for mechanical reasons. Plenty of extra fuel filters should be stocked since clogged filters are a huge problem in Puerto Rico. Fuel supplies and generators should be secured against theft. One office I was in had all the diesel in the storage tank sucked out and hauled away by a tanker truck on the street using a long hose and pump. That office failed a few hours later... after the thieves were long gone.

It is important to include security in any evaluation. What happens if the security guards can't get to an office? Passive security systems should include fences with gates, secondary barriers such as heavy exterior doors, and interior locked doors to prevent easy access. Very few of the offices in P.R. have all three and in several, the generators are inside the fence with no other protection.

The communications infrastructure was designed in a way that was vulnerable. Most offices were connected by fiber rings. Guess what happens when both loops of the ring are destroyed? There was one office I went into that had generator running, lights on, but the equipment was sitting there incapable of loading and handling calls because all fiber connections were severed and the equipment was incapable of booting without a link to the host server. Ask yourself, "what would happen if all comm links and commercial power to this center were destroyed" and act on that basis!

Nobody thought about what would happen if the roof started to leak. It would have been easy to design the interior of the equipment room so that water would be diverted by plastic sheets away from critical equipment. Slightly acidic rainwater filtered down through broken concrete picking up a load of minerals along the way. The water dripped onto and through equipment frames shorting out power converters and eating away copper backplane etching. Flooding damage should be evaluated given that most flooding could be prevented by placing the equipment on the 3rd or 4th floor of the buildings. I would strongly advise never placing critical communications infrastructure where it is vulnerable to flooding even in that hypothetical once in a thousand years flood. This is particularly relevant to power systems such as rectifiers and battery backup given that they are almost always in the basement!

The most critical suggestion I can give - and this based on Katrina, Maria, and Harvey damage - is to thoroughly think through what will happen if an entire region is devastated and prepare accordingly. Operator systems were all hosted from a single switch in New Orleans when Katrina hit. I spent a week working on an office in another city to transfer operator capabilities. Tandem capabilities in Puerto Rico are limited to 2 key systems. One of them was down last week. If not for the redundancy provided by the second tandem, the island would effectively have gone off the air for most calls. I would much rather have had 3 tandems given that all of them will be running on generators for an extended time.

The SS7 network controls signalling between offices. There are two STP's serving most regions of the U.S. This is highly vulnerable if those links are severed. Many of the offices I was in would have been capable of handling calls if some trunks had been retained using MF signalling which does not require SS7 messages to set up a call. The SS7 network is an "all your eggs in one basket" situation and the basket is precariously balanced. I would prefer to have communications capacity outside the SS7 network including MF trunks and IP links.

Another vulnerability is that remote maintenance links relied on a single piece of equipment. When that equipment went down, it was no longer possible for support personnel located in mainland U.S. to access the offices. Given how critical maintenance and support is in an emergency, it would have been far better to have at least 2 and preferably 3 methods to remotely access these systems.

I'll toss in a few thoughts about cellular phones since they are working in many areas of Puerto Rico. It is critical to have backup plans made and equipment prepared for an emergency. An operating company could easily have emergency balloons and transmitters ready to deploy. Infrastructure can be designed such that redundancy and survivability are built into the systems.

Have a plan!

Have a backup plan!!!

and have an emergency plan just in case the backup plan fails!!!!!
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Old 2017-10-26, 15:44   #130
chalsall
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Quote:
Originally Posted by Fusion_power View Post
Have a plan! Have a backup plan!!! and have an emergency plan just in case the backup plan fails!!!!!
Thank you! Important first-hand knowledge.
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Old 2017-10-27, 02:43   #131
LaurV
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@Fusion: very, VERY big BIG claps! for what you do, and for describing it here.
I literally gulped your last posts... love the style... :kotgw:

Last fiddled with by LaurV on 2017-10-27 at 02:44
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Old 2018-06-25, 21:24   #132
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So, it looks like solar panels might get as cheap as 24 cents per watt by the end of the year.

$0.24/w * 5000 = $1200
That is the size of a nice home system.
Let's set the of the other hardware (inverters, etc.) and add just as much for the install labour. That is $3600.

I looked at the rebates and tax credits for Texas and the system might be nearly free.
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