California power grid, wildfires 17

[JayMaechtlen]

So, among our various issues in California, we have an aging electric grid.
It may be more an economic /political issue than engineering?

https://www.wsj.com/articles/pg-e-k...park-wildfires-and-didnt-fix-them-11562768885

https://www.nytimes.com/2019/02/28/business/energy-environment/pge-camp-fire.html

Even in spite of massive intentional blackouts, it seems that one or more of our recent/current fires were caused by power lines.

Of course, people don't like wide cleared areas along power lines, but maybe that would be a big starting point.

Thoughts?



Jay Maechtlen

http://www.laserpubs.com/techcomm

 

[stevenal]

PG&E Inspections of Equipment That Sparked Deadly Camp Fire Were Flawed, State Regulators Say

 

[davefitz]

According to the recent article in the Nov 2019 POWER magazine, none of the existing 674 nuclear reactors on planet earth were built based on economic justification, and all were constructed using some form of military , scientific, or national objective as the primary rationale. The local laws or regulations were deliberately adjusted to ensure adequate remuneration for the clients and fabricators. Once a country is invested in nuclear plants, then it remains necessary to retain nuclear expertise for the indefinite future until the waste products are permanently dipsosed of, and this could imply artificially enhancing the career prospects for nuclear technicians for centuries ( a so called nuclear priesthood).This may explain HPC ( and Vogtle), since it was reported that it will take a minimum of 120 yrs to retire Windscale ( and hanford). The genie simply refuses to go back into the bottle.

The design code for reactors includes fatigue provisions, but the installed base of reactors are not designed for fast load changes or fast startups. The ASME boiler design code (ASME section I ) however does not even contain a single instance of the word "fatigue", and large coal fired boilers and HRSGs designed only to section I might not have specifically been designed for fatigue damage unless the mfr added his own provisions for fatigue , using either asme sect VIII div 2 or EN- 12952-3 fatigue guidelines.

The large number of HRSG's designed in the bubble period 1999-2009 were designed for the highest possible efficiency at full base load due to the high cost of natural gas during that period, and were not designed for fast startups nor 2 shift cycling operations.The fracking revolution in the US reduced the price of fuel gas by a factor of 5 after 2009, and the increasing use of renewable power ( wind , solar PV) forces combined cycle plants to 2 shift cycle and also places a large economic bonus on plants that can start up quickly . This new design objective implies fatigue damage plays the primary role in the design of the HRSG and related plant systems, to allow fast startups.

The newest frame gas turbines can allegedly turn down to 15% MCR load to allow spinning reserve operation. The installed base of older combined cycle plants could theoretically be retrofit with modifications to also allow spinning reserve operation, which in turn permits fast load increases as the components remain in a hot standby mode.However, such modificaitons do not seem to be pursued and these older plants are losing economic relevance.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

 

[Prof. Circuit]

We want taxpayers' money to be used to prevent fires, not to put them out。

 

[IRstuff]

"We want taxpayers' money to be used to prevent fires, not to put them out"

We're now re-learning the lesson that the very prevention of forest fires leads to the disasters we have now. We learned this lesson 20 yrs ago, but apparently forgot it. Had we allowed the random fires that naturally start to run their courses, there would have never been the thick buildup of brush and undergrowth that sustain today's fires to the point where all the trees completely burn.

And DON'T build in the f***ing forest!

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[VEBill]

"And DON'T build in the f***ing forest!"

Our house is in the forest, surrounded by trees. But forests in Nova Scotia are typically so damp that they're less likely to catch fire. It's not impossible, but it's not a huge concern either.

Last night we had a wind storm (gusts ~110 kmh), and there are now hundreds of power outages. Many outages would have been caused by swaying trees contacting the medium voltage lines. No reports of forest fires.

Acknowledge that the situation in dryer climates is different.

 

[IRstuff]

In California, we've been in drought conditions, off and on, for a decade. The intermittent rain pattern, I think, makes the situation worse, since it naturally selects faster-growing plants that might be less robust against fire. And, large parts of California are borderline desert to start with.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[davidbeach]

And much of that has a fire based ecology anyway. Nature wants to burn in much of California, that's how the ground is cleared and seeds released for the next generation of plants. It needs to burn, but many small fires will accomplish that better than infrequent conflagrations.

 

[IRstuff]

Sure, but Smokey Bear signs are still abound.

At this time in history, even "controlled" burns are dangerous; we've had a few get out of "control," simply because there's way too much fuel.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[davefitz]

A large part of the problem is that the state and the counties continue to permit building homes in areas that have a high risk of fire. If that permitting process cannot be halted, then the design standards for those homes must be made more " fire resistant" ( steel roofs, hardey board siding, steel window shutters, increased clearance to brush) and the insurance premiums jacked up to stupid status. And, most important of all, the residents should stop b##ching after each and every fire, as if they didn't know it was an accepted risk.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

 

[IRstuff]

Brush clearance isn't remotely going to hack it for the big fires, particularly when those types of fires can jump 4-lane highways. There are lots of roofing materials that provide comparable fire resistance besides steel. But all of them (steel, concrete, aluminum, slate) are substantially more expensive than the typical asphalt shingle roofs; they can easily add $30k cost to a small house.

But, I've got a similar beef with those that build on flood plains and then re-build with no changes on the same plot, knowing they'll get flooded in a few years. Most such houses need to be sitting on a minimum of 6 ft stilts.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[3DDave]

Brush clearance reduces radiant heat load. It may not prevent the fire from spreading, but I look at the Paradise Hospital which was successfully defended by one guy with a small watering hose able to keep ahead of the embers.

 

[Compositepro]

I believe a major factor causing the increasing damage caused by wild fire are the mandatory evacuations being so strictly enforced. If there is no one around to put out those tiny embers, fires will start.

 

[3DDave]

I don't know how slight that is - Paradise satellite photos showed the entire area was packed with fuel; there were whole neighborhoods where only small amounts of house roofs were exposed under trees, with trees covering what appeared to be 80% of the ground. Once that goes it's like being under an oven broiler.

 

[itsmoked]

Ummm, it was burning at 48.6 acres PER MINUTE. Traversing at 40 meters per second. 89.5mph.

Good luck with your garden hose.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[DM61850]

How hard would it be to build a house that could survive a forest fire relatively undamaged and be able to house occupants? During the last fire, there was a guy who didn't leave and he was out there with a water hose and rake and he managed to get through it. Not that is a benchmark but it makes you wonder if it would be easier to force everyone to have fire proof homes than to manage the forest.

 

[CWB1]

My wife the firefighter would say that all fires are dangerous and none minor, its simply a matter of landowners and the state both taking responsibility for the necessary maintenance. My property is roughly centered in a large hilly subdivision of larger wooded lots, most well over an acre. Many of us have a significant patch of woods and every few years we bring in the fire dept and have a community burn day. Growing up on the farm in NY we participated in larger controlled burns of govt land, and burning was how the family sawmill rid itself of the slab pile annually. I don't think the extreme greenies were ever happy about it, but that's how its always been done and can be a very safe activity if folks are proactive about it.

 

[VEBill]

Dave's point about "...like being under an oven broiler" is extremely important.

Far too many people don't instinctively know about radiant heat.

---

Years ago, there was a local news item about a forest fire. One house in the path of the advancing flames was shown being covered with some sort of wet thick spray foam. Of course it survived unscathed while everything around it burned.

I'm left wondering why this isn't a regular option by now.

 

[IRstuff]

Far too many people don't instinctively know about radiant heat.

I think they do "instinctively" know, but they don't know the physical process, since pretty much everyone has felt the radiant heat from the sun, stove, light bulbs, etc. What might be surprising is the sheer intensity of even a simple brush fire

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[VEBill]

It's the effect of the solid angle (steradians) that is so often unexpected.

Bleves (boiling liquid expanding vapor explosions) can be dangerous for the same reason.

 

[itsmoked]

You can build houses that won't burn. That's what should be done. They may look a bit different but that's just the requirement for living in that kind of space. There's a standard for making or building fireproof (from external causes) houses. I think they should should be a bit more radical than the "Fire Resistant" requirements and make them fire proof. That way everyone can shelter-in-place while not fleeing into the unknown of the roads during a catastrophe.

These three houses were the only ones in the area built with ICF tech.

This house was also ICF with the exception of the garage that in a subsequent fire burnt to the ground but it left the house undamaged. That's a wood structure against the house that couldn't even burn the house!!

Same goes for hurricanes. You can build hurricane proof houses and they all should be.

Keith Cress
kcress -

http://www.flaminsystems.com