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NASA Power Technology

NASA Images of Puerto Rico Reveal How Maria Wiped Out Power On the Island (jalopnik.com) 180

An anonymous reader quotes a report from Jalopnik: Hurricane Maria was the most devastating hurricane to make land in Puerto Rico in nearly 100 years and the country is still reeling in its wake. Much of the island still doesn't have running water, reliable communication or electricity. Recently, NASA published a set of date-processed photos that show the island's nighttime lights both before and after the storm. Here, you can see images of the country's capital, San Juan, on a typical night before Maria. It's based on cloud-free and low moonlight conditions. Conversely, the following composite image is of data taken on the nights of Sept. 27 and 28 -- nearly a week after the storm hit -- by the Visible Infrared Imaging Radiometer Suite, a scanning radiometer that collects visible and infrared imagery of land, atmosphere, cryosphere and oceans, according to NASA's website.
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NASA Images of Puerto Rico Reveal How Maria Wiped Out Power On the Island

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  • by Viol8 ( 599362 ) on Tuesday October 03, 2017 @05:19AM (#55299779) Homepage

    ... it might be a sensible idea to bury electric cables rather than running them around on fragile masts and poles everywhere?

    • by JustOK ( 667959 )
      no, it's not always a sensible idea.
      • by Viol8 ( 599362 )

        Why not? Its done in a lot of places in europe.

        • Exactly. I know the UK is hardly subject to hurricanes but most of our low voltage cables are buried. It's only the high voltage (tens of kV) that are often above ground and even then, a lot of these are buried.

        • Heat dissipation, for one. Current carrying cables in the air dissipate the heat of electrical power much more efficiently than those inside underground conduit.
          • by ffkom ( 3519199 )
            Air conducts heat pretty badly (also in comparison to "ground"). And no, I never heard of any power line in the ground to overheat.
            • by rmdingler ( 1955220 ) on Tuesday October 03, 2017 @07:54AM (#55300347) Journal
              Underground Electric Transmission Lines. [wi.gov]

              The design and construction of underground transmission lines differ from overhead lines because of two significant technical challenges that need to be overcome. These are: 1) providing sufficient insulation so that cables can be within inches of grounded material; and 2) dissipating the heat produced during the operation of the electrical cables. Overhead lines are separated from each other and surrounded by air. Open air circulating between and around the conductors cools the wires and dissipates heat very effectively. Air also provides insulation that can recover if there is a flashover.

              • by Anonymous Coward on Tuesday October 03, 2017 @08:09AM (#55300427)

                To further support your point, National Electric Code requires a much thicker wire gauge for buried/raceway applications. Or rather, for any given wire gauge the allowable amperage is much lower if buried, so I suppose it doesn't matter if you're already going to massive overspec your run.

                Take 4/0 copper and 75C rated wire. In free air it's legally rated to 360 amps. Buried, it's legal up to 230 amps.

            • by Anonymous Coward

              Air may conduct heat badly, but it does a significantly better job than soil at convecting it away from the source.

            • by Strider- ( 39683 )

              Right, but overhead cables aren't insulated; the conductor is directly exposed to the air.

              Underground cables, on the other hand, must be electrically insulated, and most electrical insulator materials are also pretty decent thermal insulators. Thus, in order to prevent the cable from heating up and destroy the insulation and/or blow up.

        • by YrWrstNtmr ( 564987 ) on Tuesday October 03, 2017 @08:31AM (#55300561)
          Why not? Its done in a lot of places in europe.

          How deep is the water table?
          What might they be drilling through? Dirt, or rock?

          Just saying...the easy assumption to bury might not be as easy as "Just do it".

          During/after Hurricane Isabel a few years ago, my neighborhood was the only one in the area with power. But is not always 'the answer'.
          • Why not? Its done in a lot of places in europe. How deep is the water table? What might they be drilling through? Dirt, or rock? Just saying...the easy assumption to bury might not be as easy as "Just do it". During/after Hurricane Isabel a few years ago, my neighborhood was the only one in the area with power. But is not always 'the answer'.

            Most coastal areas in Florida have also switched to buried power lines. Even in areas where the water table is, according to the map I am looking at, zero to five feet, or five feet to ten feet. But the soil in Florida is very soft and sandy. My dog once dug a 4 or a 5 foot deep hole in a matter of hours.

          • by houghi ( 78078 )

            How deep is the water table?

            In The Netherlands? Pretty deep on average.

            To be fair, you still see a lot of cables in the air, but not in cities or villages where there is already a lot of groundwork happening, just to get waste-water out.

            So if the city is build on rock, to will the rest be on rock.

            • It is a silly comment both of you just made.

              The water table isn't bad for cables, and by countering with the Netherlands you've actually pointed to one of the key points the GP was making: the high water table and soft sub-ocean level dirt / sand mixture that much of the country is made of is actually really really easy to trench and dig, which is why you won't typically find overhead powerlines here.

              Trenching is hell expensive. But it is always a risk vs cost thing, and both of those are highly dependent o

        • Tropical climates are hell on medium voltage insulation underground. You have water, insects, and heat to contend with. Salt and dust on insulators above ground are much easier to deal with.

      • by aaarrrgggh ( 9205 ) on Tuesday October 03, 2017 @08:40AM (#55300607)

        Failure rates for underground cables are higher in normal operation, and are more sudden and difficult to repair compared to overhead. You might get it for a residential subdivision, but not for the distribution network.

        The real problem is that the poles are too far apart resulting in dramatically higher wind loading in a direction they have little capability to resist. Coupling that with the complete lack of maintenance, poor quality repairs, extremely high centralization of substation infrastructure, and transmission towers that are likely as under-designed as the island's cell towers, it is pretty easy to see why we are here.

        We were trying to get a redundant feeder to a site there, and it was essentially impossible. Their grid was bare bones to say the least.

      • I don't think he was asking if it's always sensible. It looked more like he was asking if it might be a sensible idea on an island subject to hurricanes. More specifically, I bet he was asking about Puerto Rico.
    • But that takes money (Score:4, Informative)

      by Anonymous Coward on Tuesday October 03, 2017 @05:34AM (#55299829)

      Puerto Rico's government drove the island to bankruptcy. [nytimes.com]:

      With its creditors at its heels and its coffers depleted, Puerto Rico sought what is essentially bankruptcy relief in federal court on Wednesday, the first time in history that an American state or territory had taken the extraordinary measure.

      The action sent Puerto Rico, whose approximately $123 billion in debt and pension obligations far exceeds the $18 billion bankruptcy filed by Detroit in 2013, to uncharted ground.

      ...

      Of course the pols in charge in Puerto Rico are now casting about blame to deflect attention from their own contributory negligence.

      • by Anonymous Coward on Tuesday October 03, 2017 @07:00AM (#55300111)

        While other states have representatives to bring home pork spending, Puerto Rico does not. In addition, the median household income is $18K compared to Mississippi, where where the per capita income is $40K. How much can you really tax a household that only makes $18K? No companies will target Puerto Rico as a market. It's expensive to ship food there from the COTUS. In addition, if the island was already in debt, a substantial portion of the revenues are going to pay off the debug.

        So it's easy to say the government "drove the island to bankruptcy" implying that funds are being mismanaged. Even a new government would not be able to change the status quo because they are starting from such a deep hole. When the federal government needs to get out of a recession, they use deficit spending, and the closest thing a state can do to do that (which is not really ethical but there are no other options) is to issue bonds, and then default on them (bankruptcy).

        • by naughtynaughty ( 1154069 ) on Tuesday October 03, 2017 @08:08AM (#55300415)

          Mississippi's per capita income is approximately $20k, not $40k.

          You probably meant median income for both Mississippi and Puerto Rico.

        • While other states have representatives to bring home pork spending, Puerto Rico does not. In addition, the median household income is $18K compared to Mississippi, where where the per capita income is $40K. How much can you really tax a household that only makes $18K? No companies will target Puerto Rico as a market. It's expensive to ship food there from the COTUS.

          So you propose ... what?

      • Puerto Rico's government drove the island to bankruptcy. [nytimes.com]:

        With its creditors at its heels and its coffers depleted, Puerto Rico sought what is essentially bankruptcy relief in federal court on Wednesday, the first time in history that an American state or territory had taken the extraordinary measure.

        The action sent Puerto Rico, whose approximately $123 billion in debt and pension obligations far exceeds the $18 billion bankruptcy filed by Detroit in 2013, to uncharted ground.

        ...

        Of course the pols in charge in Puerto Rico are now casting about blame to deflect attention from their own contributory negligence.

        Oh sure, quote a right-wing rag like the NYT ;)

      • Unfortunately that articles leaves out the changes to US tax policy [cnbc.com] that lead to the current conditions. It also leaves out the influence of the protectionist Jones Act [wikipedia.org], which considerably increases the cost of living on the island.

    • by The Cynical Critic ( 1294574 ) on Tuesday October 03, 2017 @05:41AM (#55299863)
      Obviously, however the reason why they put them on poles in the first place is because it's considerably cheaper than run them underground and if you've paid any attention to what's been going on there for the last few years you'll know they don't exactly have the money for this just lying around.

      To put the cost into perspective, here in Finland, where we don't have the same debt and budgetary problems, they only relatively recently started mandating companies put a significant effort into moving the above-ground powerline infrastructure under ground and the current plan is to have 65% of the low voltage and 47% of the medium voltage infrastructure moved to underground cables by 2029.
      • by Viol8 ( 599362 )

        Its not like their grid was put up last week. They've probably had 100 years of electric power in which to think , "Y'know, maybe we should put these cables that keep falling down in hurricanes underground?"

        • If they weren't able to muster the effort required to get the necessary investment lined up at any point in the last 100 years, what makes you think they'll be able to get it done when their financial situation is what it is today?
        • Hurricanes Hugo and Georges (1989 and 1998 respectively) both wiped out more than 90% of the power infrastructure of Puerto Rico. But each time it was rebuilt as before...
    • Re: (Score:2, Informative)

      by Anonymous Coward

      One word: flooding.

      Sorry, thanks for playing, but there is no easy answer.

      • by rmdingler ( 1955220 ) on Tuesday October 03, 2017 @07:14AM (#55300173) Journal
        Flooding is actually less of problem for underground cable than you might think. There is always water present in underground conduit, and the wiring is jacketed to account for it.

        The location of junctions and transformers is the most important consideration, and if you get those above the flood level, you are likely in good shape.

        Underground municipal infrastructure is usually saturated with water and sewer lines, so even if money isn't a factor in the design, space constraints often are.

        • by jabuzz ( 182671 )

          Except take a trip over the pond to the UK and most local electricity lines are under ground along with the gas, water, sewer and telecoms. Everything since WII is all underground apart from telephone, where everything in the last 40 years is underground. The idea that space constraints prevent putting it all under the ground is uninformed nonsense.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      My rural Cooperative charges $3 per foot for overhead lines to a private dwelling. They charge $15 per foot for underground. Overhead lines make much more sense especially when such great devastation is not expected each month. Privately owned generators can be used to power pumps for water, refrigeration, or lighting and are used here for our power outages that can be expected every year or 2.

    • by ffkom ( 3519199 )
      How can you dare to propose such? Where should this end? Buiding houses from stone and concrete instead of wooden slats?!? That is so un-american!! You will be ridiculed as "Captain Hindsight" if you continue to make such statements!

      The only true patriotic way to handle this kind of catastrophy is to briefly mourn about the dead, have some inspiring pep-talk, then re-build everything the same cheap, brittle way it was build before, and then pray harder than before catastrophy won't strike again.
    • Sure, are you going to pay for it?

      Power isn't run above ground because it makes the skyline look pretty.

    • No no no!
      That would be to smart!

      And it would safe to much money.
      And think about the unemployed ... how would they get a seasonal job after the rain/hurricane season?

  • by 140Mandak262Jamuna ( 970587 ) on Tuesday October 03, 2017 @06:05AM (#55299921) Journal
    These photographs don't shed any light on how the grid was wiped out. It just shows how much. Which we already know. Just a little bit more graphic. That is all.
    • by Anonymous Coward

      Exactly what I wanted to say. When the power goes out after a windy storm in New England we all know HOW we lost power because we grab our chainsaws and cut up the trees that have fallen on the power lines. "Wutya reckon knocked the power out?" "I got no idea but at least we got some wood for the fireplace now."

      I guess BeauHD was in a hurry to post content and accidentally omitted the word "much".

    • Re: (Score:3, Interesting)

      Yes, it was a really disappointing article. We know the power is out. 'NASA' wasn't needed to show us that. The whole article appears to be a puff piece. A gee-whiz article not suitable for Slashdot readers.

  • by Dutch Gun ( 899105 ) on Tuesday October 03, 2017 @06:35AM (#55300019)

    I love how, in the comparison images, someone actually felt the need to label darker areas as "less lights" and brighter areas as "more lights."

    Also, how pedantic would it be of me to point out that it should be "fewer" lights, not "less"?

    • Re:Less is More (Score:5, Informative)

      by Mal-2 ( 675116 ) on Tuesday October 03, 2017 @07:30AM (#55300239) Homepage Journal

      Nope, they got it right in a somewhat awkward way. They aren't counting those lights, but rather mapping the overall intensity at given locations. If it's not a countable quantity but rather one of magnitude, then "less" is correct. The use of "lights" rather than "light" may be throwing you off.

    • by ceoyoyo ( 59147 )

      If you don't put a colour scale on your graph some pedant will point it out. So you put one on even if it should be perfectly obvious.

      The answer to your second question is, not pedantic enough. The label should read "less light" not "less lights" or "fewer lights" because the satellite is incapable of counting individual light sources.

    • Also, how pedantic would it be of me to point out that it should be "fewer" lights, not "less"?

      If you want to be super pedantic then point out that counting working lights from space on a small heatmap isn't really representative. The issue isn't with less or fewer lights, it's that they used the word "lights" instead of the word "light". :-)

    • It's for the blind when the translate it into braille.

  • "the country"? (Score:5, Informative)

    by j-beda ( 85386 ) on Tuesday October 03, 2017 @07:25AM (#55300213) Homepage

    A large part of the challenges that Peurto Rico faces is that it is not in fact a country, but rather it is an "unincorporated territory of the United States located in the northeast Caribbean Sea".

    https://en.wikipedia.org/wiki/... [wikipedia.org]

    https://www.thoughtco.com/puer... [thoughtco.com]

    Peraps if Peurto Rico was a country (or a "state" within the United States), they might have been better able to respond to the types of problems that this storm has caused.

    WIth a population of a bit more than 3.4 million, the territory seems to have more people than twenty-two other US states:

    http://worldpopulationreview.c... [worldpopul...review.com]

    • They could have chosen statehood or independence. There has been 3 different votes since 1998.
      https://en.wikipedia.org/wiki/... [wikipedia.org]

      Why does PR keep choosing the status quo?

      • by olau ( 314197 )

        Eh, did you read your link? It says that they choose to become a state in November 2012 and then asked the US to enable them to become one.

        I think a better question is, why have they been stalled since?

        • Puerto Rican voters were asked two questions: (1) whether they agreed to continue with Puerto Rico's territorial status and (2) to indicate the political status they preferred from three possibilities: statehood, independence, or a sovereign nation in free association with the United States.[2] 970,910 (54.00%) voted "No" on the first question, expressing themselves against maintaining the current political status, and 828,077 (46.00%) voted "Yes", to maintain the current political status. Of those who answered on the second question 834,191 (61.11%) chose statehood, 454,768 (33.34%) chose free association, and 74,895 (5.55%) chose independence.[3][4]

          The governor-elect Alejandro García Padilla of the Popular Democratic Party (PPD) and several other leaders who favor the present status had recommended voting "Yes" to the first question, and leaving the second question blank as a protest to what they said was "an anti-democratic process" and "a trap"

          Because there were almost 500,000 blank ballots, creating confusion as to the voters' true desire, Congress decided to ignore the vote.

          History professor Luis Agrait explained the result in this manner to CNN: "If you assume those blank votes are anti-statehood votes, the true result for the statehood option would be less than 50%." Considered as a percentage of the total number of votes cast in the first ballot, 44% voted in favor of statehood on the second ballot.

          IOW, because it wasn't clear the results were ignored. Is a vote valid if the questions are poorly constructed? This has been the case for many of the referendums. Not saying it is right or wrong but if you make a decision with such permanency as statehood then the results should not be doubted to such an extent.

          • IOW, because it wasn't clear the results were ignored

            97% voting for statehood isn't clear?

            • You must be talking about the 2017 referendum not the 2012 referendum.

              A referendum on the political status of Puerto Rico was held in Puerto Rico on June 11, 2017. The referendum had three options: becoming a state of the United States, independence/free association, or maintaining the current territorial status. Those who voted overwhelmingly chose statehood by 97%; turnout, however, was 23%, a historically low figure. This figure is attributed to a boycott led by the pro-status quo PPD party.

              Again, there wasn't a clear majority because of the boycott. Should the US just ignore that and try to force PR to be a state which is permanent? At what point is the future of PR the fault of PR?

              • Again, there wasn't a clear majority because of the boycott.

                You don't call 97% a clear majority? Oh, you mean a majority of eligible voters? I'm sorry, but democracy does not work that way. You either vote, or your opinion doesn't count.

                Using your argument, no recent US President had legitimacy, because less than 50% of the eligible voters voted for him.

                In the case of Trump, less than 27% of eligible voters voted for him. Should he be ignored because of this?

                • 'Clear' is the keyword. Many elections are suspect if the opposition steps out particularly when the result is so one sided (95%+) when that only happens in dictatorships, for the most part. It doesn't mean it is illegitimate or does not represent a voting majority. The issue is that there needs to be a clear decision that isn't muddied by boycotts or poor wording. A strong vote with a strong turnout is needed. Why this hasn't been achieved in PR, I don't know.

                  There are two things stopping PR statehood; PR

    • A large part of the challenges that Peurto Rico faces is that it is not in fact a country, but rather it is an "unincorporated territory of the United States located in the northeast Caribbean Sea".

      And to top it off, most people can't find Puerto Rico to help out because so many people misspell the name!

      • by j-beda ( 85386 )

        A large part of the challenges that Peurto Rico faces is that it is not in fact a country, but rather it is an "unincorporated territory of the United States located in the northeast Caribbean Sea".

        And to top it off, most people can't find Puerto Rico to help out because so many people misspell the name!

        Yeah, those people are idiots!

  • If you look at the pics, you'll notice the areas with buildings that had distributed microgrids of power, as in houses with some solar or wind that could be protected or taken indoors, were the first to regain power, followed by diesel backup generators that either pre-existed or were provided by the military or commercial/private interests.

    While it is true that undergrounding is a good choice, it would not have prevented blown transformers, flooded power generation sites, storm damage to all utility power

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