How the U.S. Power Grid Is Like a Big Pile of Sand

[Slimprofits]

Mental exercise - think about how these properties apply to all complex, interdependent systems and entities: economies, companies, nation-states, etc.

In other words, the grid may be not be the "right" size—big enough to distribute power efficiently, but small enough to prevent widespread blackouts, such as the 2003 blackout that cut power to 50 million people in the U.S. and Canada for two days. So, breaking up the system into smaller grids could reduce the likelihood of power outages, according to a new study in the journal Chaos, published by the American Institute of Physics.

"We found that for the best trade-off between providing backup power and blackout risk, the optimal size was 500 to 700 nodes," Newman said. The bigger the grid gets, the greater the risk of failures.

"Sandpiles are stable until you get to a certain height. Then you add one more grain and the whole thing starts to avalanche," Newman said. "This is because the pile's grains are already close to the critical angle where they will start rolling down the pile. All it takes is one grain to trigger a cascade."

article link: http://www.nationaljournal.com/tech/...-sand-20140408 ------ study link: http://scitation.aip.org/content/aip...1063/1.4868393

The simulation results also show that medium size blackouts occur significantly more frequently in the multiple 100 node networks. In the large connected size networks, the large blackouts, although less frequent, increase greatly in relative frequency as a result of increasing the number of nodes. The emergence of the power tail for the large networks is characteristic of a system displaying critical behavior and is the main drawback of these large complex systems. This is why the advantage of a wider range of power dispatch options can turn into the large disadvantage of the increased risk of very large blackouts due to the increased probability of large cascading failures.

When we compare the risk function for the case of multiple 100 networks to that for large networks, we find the risk for the multiple 100-node networks has a large peak, due to high frequency of the blackouts, at medium values of load shed, while in contrast, the large networks show a slowly decreasing tail for very large values of load shed. Therefore, the cost of the large events may dominate the overall risk as the size of the system increases. This dominance depends on how fast the cost of the events increases with its size and how fast its probability decreases.

[lektrode]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

this all suggests that having some sort of backup power system/source on ones own property (solar/PV with BATTERIES and/or genset + heatsource/propane etc) starts to make sen$e ?

[Slimprofits]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

this all suggests that having some sort of backup power system/source on ones own property (solar/PV with BATTERIES and/or genset + heatsource/propane etc) starts to make sen$e ?

If I owned a home in an area that needs electricity for heating in the winter I would own a backup generator.

[lektrode]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

If I owned a home in an area that needs electricity for heating in the winter I would own a backup generator.

nears i know, just about all forms of space heating require some electric source - other than woodstoves or passive solar.

but short of full ops capable PV - with space heating via some method of combustion (assuming no passive solar, since only the PacNW has 'lektric cheap enough to heat houses - via hydro+nukes) - my preferred backup would be batteries and an inverter plus a genset to recharge the batteries - that way quikie outages arent so disruptive and ya dont have to listen to a generator grind away all night (assuming a batt bank big enuf to go 12hours or so)

[Slimprofits]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

I would have responded the same way even before thinking about this study. That's based on experience with winter power outages in New England.

[lektrode]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

I would have responded the same way even before thinking about this study. That's based on experience with winter power outages in New England.

oh trust me on this one, slim - i've got decades of experience in that dept too - but...

the reason why - IMHO - that an inverter and batteries makes a better backup solution is simple:

most outages last from minutes to a few hours (and i typed MOST) - if not a couple seconds...

read: just long enuf to require reset of all the 'lektronic time keepers, if not ruin your evening by shutting down just as the good part of the movie/game/music, whatevah - gets under way

a grid-tie inverter (w charger) has a transfer switch that shifts from juice INTO the batteries to juice OUT OF the batteries in the blink of an eye - the good ones are fast enough so that even computers wont notice - meaning: you wont even know the power went off, as the lights dont even blink.

then its just a question on how much peak power (watts) you'll need on what specific circuits you'll want to backup
plus how many hours-worth you want to spend on batteries

now - contrast this with a generator for backup: and this assumes one has a high-end genset, with grid voltage sense capability... that typically work like so...

it eventually senses that the juice = dead and initializes its startup proceedure, hopefully kranks, fires-up and spins-up to the rated RPM, checks itself to see if all is well - and still dead on the house circuit - and then - assuming it also has a transfer switch - flips the house over to the genset as the source

so far, so good - right?
except that you are in the dark during some number of seconds to minutes while all this happens.

and THEN you're hoping that all is well on the combustion-end of the genset - like all the maintenance/exercising has been done every some number of weeks - that the fuel source is present/clean etc - not to mention connected, with the valves turned on etc - or that some rodent hasnt built a nest in the air intake - just a few of the common issues with trying to keep a genset WORKING when you need it to.

and it also needs a battery - to auto-magically krank up at the moment of truth.

unless you go with my fave backup genset - which doesnt need any sort of 'periodic' maintenance if you dont use it (and keep the gastank empty/dry) - and with my theory about length of most outages being measured in minutes or hours - you'd only need to think about even running it should the grid go down for longer than your battery bank will last

other than that, changing the oil every couple of years has been all i've ever needed to do with mine.

and if you use good batteries, you only need to think about them every 4,5 or if yer lucky - every 6years or so

vs having to give the larger/stationary power plants a good going-over every few months - IF you'd like to make sure it'll go when you need it to

is all i'm trying to say.

[shiny!]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

and if you use good batteries, you only need to think about them every 4,5 or if yer lucky - every 6years or so

Which ones on that page do you recommend, Mr. 'trode?

[lektrode]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

Which ones on that page do you recommend, Mr. 'trode?

hey ms shiny!
genl'y, the marine/deep cycle type - altho not sure/doubt theres much diff tween the rv type or their solar models

[shiny!]

Re: How the U.S. Power Grid Is Like a Big Pile of Sand

Thank you, sir.