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Wildfire threatening the power grid that supplies San Francisco

npr.org

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Re: Wildfire threatening the power grid that supplies San Francisco

#41

Post by hga »

tehwalrus wrote: post #33
hga wrote: post #27

Earlier quoted context omitted.

Waste != Materials. These reactors by definition have a fair amount of very "hot" materials; it hardly matters if none of them are declared "waste" if they'll still kill you in a few minutes of direct exposure.

... molten salt reactors (the kind in the comment at the top of this thread) are at atmospheric pressure, and are designed with a drain plug which isolates the (very hot) materials from the neutron source, after which they cool down happily on their own in a separate but similarly shielded compartment. release of materials is one of the most unlikely outcomes ever .

You really can't imagine a release of materials outcome in the context of active sabotage?

(Which is relevant in the context of massive distributed ones; current nuclear power systems mitigate this by being few in number such that they can be well guarded.)

Re: Wildfire threatening the power grid that supplies San Francisco

#42

Post by sliverstorm »

tomjen3 wrote: post #12

Damn. The powers that be better do something about this fast. SF is about one of the last places in the US to develop new things. Heck just a temporary prolonged outage of Google alone would have huge negative consequences for the US (not to mention the world). Amazon AWS US west is in Northeren California. I wonder how big the negative effect will be on just how many companies?

This sort of thing is EXACTLY WHY both Google and Amazon have datacenters all over the world.

Re: Wildfire threatening the power grid that supplies San Francisco

#43

Post by joering2 »

The system continues to be broken. Hundreds of millions going into building lethal drones to deploy to Afganistan/ME; some major american cities are on a brink of releasing police surveillance drones en masse (its constitution/law-questionable now), and yet we do not have drones to fight fire.

I am pretty sure there are lot of challenges within the project, but I can envision drones working together to connect each other and transport water to sprinkle it when needed without humans being endangered. I mean, if we achieved this [1], why not go further?

[1] http://www.youtube.com/watch?v=oDyfGM35ekc

Re: Wildfire threatening the power grid that supplies San Francisco

#44

Post by ChuckMcM »

tomsaffell wrote: post #35
agwa wrote: post #31

This article is vague (and overly alarmist); other sources I have read indicate that the threat is to SF's municipal power company, which provides power primarily to municipal buildings (including, most notably, SFO!). The vast majority of people in SF and the Bay Area get their power from PG&E, which has power plants in many more places than just Yosemite. More info: http://www.sfwater.org/index.aspx?page=391

Yes, the NPR article is alarmist, verging on irresponsible. A few facts, with sources: - The water coming out of Hetchy Hetchy is still well within the 'usable' range [1] - The total loss of power is 293 MW (Holm and Kirkwood), which is a tiny percentage of the power generated in CA [1,2] - The SF PUC is already dealing with the loss of those 293 MW: San Francisco is making up the difference in power generation by ac…

Its only alarmist if it doesn't get worse :-) Seriously though, alarmist or not, its serious. This fire is growing and not contained. There exists a non-zero chance of it creating a serious impact into the available clean water supply. And this is to a county not exactly known for its fiscal responsibility or ability to respond well to crisis.

Re: Wildfire threatening the power grid that supplies San Francisco

#46

Post by hga »

fnordfnordfnord wrote: post #30
hga wrote: post #19

Earlier quoted context omitted.

To which I say BS, at least for the reason cited. Sure, the U-232 contaminated U-233 is nasty, but as long as it doesn't make it impractical to make a nuclear warhead it's quantitatively different from the uranium cycle, where after a few months at most plutonium is impossibly contaminated with two even more undesirable isotopes (one is very hot, I've seen estimates of 100kW for a bomb sized quantity (it's used for R…

These folks seem to think the problem is solvable by adding U-238 http://www.coal2nuclear.com/MSR%20-%20Denatured%20-%20CNSLeB...

Yeah, that solves it neatly.

Reduces to a protoactinium problem, it decays to U-233 with a half-life of 27 days. The article claims there's so little protoactinium in the total mass of salt and stuff that it's not practical to isolate it, at least not without detection, and failing that, not quickly. This gets into fine details beyond my level of expertise, but I agree the problem is much reduced. Although very possibly still greater than for current LEU designs.

Re: Wildfire threatening the power grid that supplies San Francisco

#47

Post by hga »

joering2 wrote: post #43

The system continues to be broken. Hundreds of millions going into building lethal drones to deploy to Afganistan/ME; some major american cities are on a brink of releasing police surveillance drones en masse (its constitution/law-questionable now), and yet we do not have drones to fight fire. I am pretty sure there are lot of challenges within the project, but I can envision drones working together to connect each o…

Errrm, this translates into a "making large drones" problem. Which has a whole set of additional problems, e.g. what are you going to say to the survivors of a devastated neighborhood when a big drone with lots of water crashes into it?

I'm not saying its insurmountable, just that it's way beyond the current levels of both drone technology and acceptance.

Re: Wildfire threatening the power grid that supplies San Francisco

#48

Post by joering2 »

hga wrote: post #47
joering2 wrote: post #43

The system continues to be broken. Hundreds of millions going into building lethal drones to deploy to Afganistan/ME; some major american cities are on a brink of releasing police surveillance drones en masse (its constitution/law-questionable now), and yet we do not have drones to fight fire. I am pretty sure there are lot of challenges within the project, but I can envision drones working together to connect each o…

Errrm, this translates into a "making large drones" problem. Which has a whole set of additional problems, e.g. what are you going to say to the survivors of a devastated neighborhood when a big drone with lots of water crashes into it? I'm not saying its insurmountable, just that it's way beyond the current levels of both drone technology and acceptance.

The biggest problem fighting fires are lethal to humans high temperatures and lack of easy access to places affected. Those two problems would be irrelevant to properly designed drones that can easy maneuver and are built from temperature-resistant materials.

Instead of huge drone carrying water (we already have planes to do that now), I was envision a network of connected drones that "pass by" the water as they hover in the line all the way from water pool to fireplace. The video attached previously shows you group of drones perfectly communicating with each other.

I never said it was easy to develop, but I have to disagree its something "way beyound the current levels" of technology. Further, the cost to design, develop and implement would be pennies comparing to an average damage of mid-size fire. Not the mention about life-loss.

Re: Wildfire threatening the power grid that supplies San Francisco

#49

Post by Stratoscope »

Stratoscope wrote: post #28

Hetch Hetchy water doesn't just go to San Francisco. Two-thirds of it goes to other cities and towns on the Peninsula, the South Bay, and in Alameda County. In particular, many cities that the Hetch Hetchy Aqueduct runs through get some of the water, because voter approval in those cities was part of the campaign to get the project built. For example, 74% of Mountain View's water comes from Hetch Hetchy. (They get 87…

I forgot to add... Here's a Street View from Ivy Drive in Menlo Park that happened to be taken during a pipeline addition/reconstruction. They set out the pipe sections in the street median before digging to lay them in place. These are some big pipes!

https://www.google.com/maps?ll=37.47579%2C-122.1629239999999...

(You may need to zoom out; I couldn't figure out how to save a URL with the correct zoom level.)

Re: Wildfire threatening the power grid that supplies San Francisco

#50

Post by davidw »

jcl wrote: post #25
argumentum wrote: post #13

Earlier quoted context omitted.

The "City" of San Francisco (though it does contain a big chunk of the tech industry and houses many of it's employees) is not the whole "Silicon Valley". Google, Facebook, LinkedIn, Y-Combinator, Stanford, Yahoo, etc are all located in the South Bay and (may or may not be, the article doesn't specify) affected by the fires.

Don't know about the power grid, but about half the water supply in Mountain View comes from local wells, so it would not be as affected as SF, but part of the rest comes from Hetch Hetchy, so there could still be problems. Not sure if local resources get reallocated in emergencies. http://www.valleywater.org/Services/CleanReliableWater.aspx

Most people think hackers don't have good personal hygiene skills anyway, so I think those companies could skate for a little bit if push came to shove...
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