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HERETIC wrote:

I like to remind these anti-nuclear activists that life on this planet would not exist without that "continuous nuclear explosion up in the sky"

...and I like to remind people who use this argument that it's apples to oranges since that's fusion, while all of our current nuclear generation plants are fission (and are likely to remain so for a long time). We also don't need to worry about problems created by the sun's spent fuel for another 6 billion years (when the buildup of helium in the core will cause it to go red giant).

That said, yes, I believe that increased use of nuclear can and should be a part of our energy strategy to transition away from fossil fuels, with a couple of caveats: 1) Older reactor designs need to be retired and replaced with newer, safer ones; and 2) Dealing with the spent fuel issue needs to be a national priority. If we build new nuclear plants today, the operational lifetime of those plants could very well give us the breathing room we need to improve our storage and transmission systems to accommodate a grid where wind/solar/etc. provide the bulk of our power.

If we want to go any further down this rabbit hole we should probably split the thread to R&P...

just brew it! wrote:

HERETIC wrote:

I like to remind these anti-nuclear activists that life on this planet would not exist without that "continuous nuclear explosion up in the sky"

...and I like to remind people who use this argument that it's apples to oranges since that's fusion, while all of our current nuclear generation plants are fission (and are likely to remain so for a long time). We also don't need to worry about problems created by the sun's spent fuel for another 6 billion years (when the buildup of helium in the core will cause it to go red giant).

That said, yes, I believe that increased use of nuclear can and should be a part of our energy strategy to transition away from fossil fuels, with a couple of caveats: 1) Older reactor designs need to be retired and replaced with newer, safer ones; and 2) Dealing with the spent fuel issue needs to be a national priority. If we build new nuclear plants today, the operational lifetime of those plants could very well give us the breathing room we need to improve our storage and transmission systems to accommodate a grid where wind/solar/etc. provide the bulk of our power.

If we want to go any further down this rabbit hole we should probably split the thread to R&P...

Technically, the Sun starts to fuse the hydrogen shell when the core gets helium ash rich. This marks of beginning of its life in the red giant branches. It is in the asymptotic red giant stage where core gets hot and dense enough to fuse the helium ash. This process usually starts with a "flash".

Redocbew wrote:

ludi wrote:

The problem is that there's a faction that hates every technology and has compelling reasons why it shouldn't be built.

Yeah, it still seems odd to me in a way, but it's true. I don't know enough about any of this to have a meaningful opinion, and honestly I'm ok with that. It seems like this is one of those topics people talk about where they trade rhetoric much more than actually talking about it.

So like pretty much every important issue in the world today?

--SS

Pretty much.  

I should qualify that with saying that I have a pretty dim view of the average person in this regard.  If it's important, then wouldn't they want to know more about it and be willing to accept a different viewpoint instead of just digging in their heels and burying their head in the sand?  Sometimes it seems like the former is a depressingly rare thing to find, and the latter is all too common.

Jumping back a little ways: I was in a gasoline car that spontaneously caught fire once. I forget the cause (I was probably 6-ish at the time), but it was at the front of the engine, not violent, and there was an extinguisher nearby, so the car was alright.

IIRC some people have had an issue with 1st-gen Imprezas (my current car) where the A/C compressor locks up, the belt slips at full speed, and a fire starts. (It doesn't apply to me because the A/C clutch is busted and won't engage in the first place, and if it did that belt would probably snap. )

Car fires happen, and not always from the obvious causes. Aside from fires being statistically a lot less likely in electric cars, when Teslas do have fires, they don't seem to be particularly quick or violent.

Redocbew wrote:

I should qualify that with saying that I have a pretty dim view of the average person in this regard. If it's important, then wouldn't they want to know more about it and be willing to accept a different viewpoint instead of just digging in their heels and burying their head in the sand? Sometimes it seems like the former is a depressingly rare thing to find, and the latter is all too common.

Word. The usual lunch crowd I hang out with has made it a philosophical point to not be averse to R&P, because why would we avoid talking (and learning) about the important stuff in the world? It obviously requires the right kind of crowd, but I think it does us a lot of good.

I don't believe the statistically less likely in electric cars part.

Car fires are not frequent and they usually are very old cars with rotten fuel lines (often caused by reformulated gas).  Old electric vehicles are not around in large enough numbers to make good comparisons.

For a personal anecdote, the only car fire I have been involved with was an electric car whose battery shorted out.  That was lead acid by the way, not the lithium batteries known for burning and exploding.

I probably wouldn't be able to find stuff again, but a discussion like this came up over on Hacker News and someone brought numbers (NHTSA, possibly?). It showed electric as quite a lot better, but probably didn't cover conversions (I assume lead-acid means conversion). Take that how you will.

On a related note, conversions are a cool thing (I'm even doing one for a friend), but their safety is very dependent on how much care goes into the build. Straight-up shorts of sufficient duration/intensity to cause a fire aren't a thing that should happen with decent design, and if they do it shouldn't start a fire because there should be a fuse fast enough to keep it from cascading into other problems. Murphy's law exists, sure, but my first thought on hearing that is to wonder how well the car was actually built.

Edit: It occurs to me that the fuse bit might be tougher with a powerful lead-acid build, because under hard acceleration it might sag the pack voltage quite a lot anyway - I_{hard acceleration} and I_{incomplete short} might not actually be that far apart. I'm used to thinking lithium for everything these days, conversions included.

It wasn't a conversion, it was just quite a while ago and was lead acid because NiMH was cost prohibitive and Lithium batteries would be a small fortune.

But about those numbers, how many EV conversions do you think would self report an electrical fire to the NTSB?

That report would go something like this "Hey NTSB, remember that EV conversion I didn't tell you about?  Well it burned up.  Bye."

If you remember, GM would only lease the EV1, not sell.  They knew if they left old EVs in the hands of the public that things would go wrong.  Corporate liability was the only reason why that happened.

Since then there was the EV mandate in California so manufacturers had to sell them.  Technology is a bit better along with crash standards but who knows what will happen when old beater EVs become a thing.  At some point a used Nissan Leaf will be out of warranty, old enough and cheap enough that some people who buy them will treat them badly, repair them improperly and something will go wrong.

Frugal wrote:

It wasn't a conversion, it was just quite a while ago and was lead acid because NiMH was cost prohibitive and Lithium batteries would be a small fortune.

Do you recall anything about the power (HP or kW or volts/amps) and range? As per my last edit, that could have something to do with fuse effectiveness, and could explain half the equation. As for the other half, I have to blame either murphy or sloppy engineering - it's one in a bajillion for a well-designed car.

Frugal wrote:

But about those numbers, how many EV conversions do you think would self report an electrical fire to the NTSB?

That report would go something like this "Hey NTSB, remember that EV conversion I didn't tell you about?  Well it burned up.  Bye."

I did say it probably didn't cover conversions, didn't I? Yeah, I did.

Frugal wrote:

If you remember, GM would only lease the EV1, not sell.  They knew if they left old EVs in the hands of the public that things would go wrong.  Corporate liability was the only reason why that happened.

Since then there was the EV mandate in California so manufacturers had to sell them.  Technology is a bit better along with crash standards but who knows what will happen when old beater EVs become a thing.  At some point a used Nissan Leaf will be out of warranty, old enough and cheap enough that some people who buy them will treat them badly, repair them improperly and something will go wrong.

That's not how I read the EV1 situation, though that might be a R&P-prone topic. I can say, as someone who is getting paid to build one of these and who put a lot of time into getting all the associated knowledge, that you're overblowing this a bit. As with gas cars, the vast majority of things that can go wrong with EVs are non-catastrophic, and there are a lot fewer things to go wrong with EVs. I'm not going to post a full reliability analysis here because I have better things to do with my time, but if you have any particular concerns, I'd be happy to elaborate.

That fire was caused by sloppy engineering, no doubt about that but unless you put a fuse inside the battery there is no way to protect against a dead short.

The incident was across two 12v batteries connected in series inside the pack so it only took 24v to start the fire. It probably wasn't enough current to blow a fuse on something that powers a car...

People talk about burning up lithium batteries but the chemistry doesn't matter if you get a short and every EV runs that risk.

But let's talk about gas tanks. People who like EVs seem to make them out to be extreme fire hazards but the reality of what it takes to cause a gas tank fire is very very uncommon and usually can be traced back to negligence of the operator or things like 60 mph rear end collisions.

It is probably more common to get burned sending smoke signals but I still think cell phones shouldn't catch on fire.

As long as EVs keep catching on fire, it is a problem.

Frugal wrote:

People talk about burning up lithium batteries but the chemistry doesn't matter if you get a short and every EV runs that risk.

Lithium is a much bigger issue, though (and we're stuck with it these days if we want decent energy density). We can make modern LiFe packs pretty safe, but they're still a much bigger worry than shorts are. (Really, manufacturing defects in / physical damage to / overtemperature of the batteries are about the only problem like this worthy of note.)

Frugal wrote:

But let's talk about gas tanks. People who like EVs seem to make them out to be extreme fire hazards but the reality of what it takes to cause a gas tank fire is very very uncommon and usually can be traced back to negligence of the operator or things like 60 mph rear end collisions.

It is probably more common to get burned sending smoke signals but I still think cell phones shouldn't catch on fire.

I never said gas tanks are big fire hazards. They're not. The issue is more with sending that fuel all around the hot engine at increasingly high pressure, as well as the numerous other potentially flammable things in an engine bay. Gas tank ignition and violent lithium battery ignition are both incredibly rare events, as in they're not gonna happen to you (unless you're in some LiPo supercar that went 100% power density, I guess). If we talk about milder fires (the ones that give you plenty of time to get out), there's a conversation to be had.

Frugal wrote:

As long as EVs keep catching on fire, it is a problem.

As long as cars keep catching on fire, it is a problem - that is, it's always gonna be a problem, because moving a car around requires storing a lot of energy, and there'll always be a way to make that energy disperse faster than we'd like.

Whether it's a problem worth worrying about is another question. I'd say no for consumers (engineering is of course a different matter), because the real problem is cars crashing into other cars. At this point, the chances of either tech self-destructing are infintesimal compared to the chance of tech-independent catastrophic deceleration.

Frugal wrote:

But let's talk about gas tanks. People who like EVs seem to make them out to be extreme fire hazards but the reality of what it takes to cause a gas tank fire is very very uncommon and usually can be traced back to negligence of the operator or things like 60 mph rear end collisions.

It is probably more common to get burned sending smoke signals but I still think cell phones shouldn't catch on fire.

As long as EVs keep catching on fire, it is a problem.

There are quite a lot of fires while putting the petrol in the car, on average about 3000 a year in the US with 2 fatalities. Sure you can put this down to idiocy and the pumps in the US not requiring you to hold on to them while filling but you're kidding yourself if you think petrol is safe.

Of course current batteries aren't safe either and charging an EV overnight in a garage attached to your house could end badly.

cheesyking wrote:

charging an EV overnight in a garage attached to your house could end badly.

To clarify that one, what batteries don't like is fast charging (both in terms of momentary stress and in that fast charging gives you a lot fewer charge cycles before the battery needs to be replaced). I think some chargers these days are close to 2C (charge current is twice the Ah rating), which I don't really like, but charging you'd do in your garage tends to be more like 0.2C, at which point there's no problem at all.

On a related note, R/C batteries have a reputation for blowing up because people buy packs rated at >50C continuous discharge and then charge them at insane speeds like 8 or 10C. Batteries that can do that are a lot less safe to start with, and charging at 10C is dire abuse. When you step back down to 25C batteries and charge them at reasonable rates like 1 or 2C, fires are a whole lot rarer (and those are still extremely sketchy packs compared to EV stuff).

just brew it! wrote:

In Illinois (and other states where a substantial fraction of the electricity is still produced by coal-fired generators) EVs and plug-in hybrids are effectively coal-powered vehicles.

The real problem is not that the electricity comes from coal; it's that the coal-fired plants are from a 19th century coal infrastructure that was developed without regard to environmental issues.

Chrispy_ wrote:

MileageMayVary wrote:

Chrispy_ wrote:

I'm a pro-nuclear advocate, given that it's far far cleaner than fossil fuels provided the waste is managed responsibly and the power production is "always on" to handle demand unlike solar, wind, hydrothermal and wave power.

As am I.
As to Nuclear's cleanliness I did some back of the napkin maths once to compare it to coal from a mining perspective (which I've never heard a comparison made). I used some somewhat vague numbers as best as I could find them and always went worst case if given a range. I picked a target number of output (like a trillion BTUs) then calculated how much coal would be needed to generate that amount. Then calculated how much reactor grade uranium would be required to generate that. Then how much raw uranium is required to enrich it to 5% U235? Something like 4.5 KG in to 1 KG usable and 3.5 KG depleted out. Then how many tons of graphite do you need to mine to produce that amount of raw uranium. I think my answer was something like 2200 times less than the tonnage of coal to produce that same thermal output.
How far off topic am I now?

Yes, exactly.
When you see these anti-nuclear activists making a fuss about nuclear waste, they conveniently forget the facts - such as how fossil fuels are several orders of magnitude worse.
It's ignorance like that which makes me angry, the same angry as anti-vacciners and their ignorant ilk make me.

I think your math was about the side of the problem that definitely favors nuclear.  The problem with nuclear is at the waste end, in several different ways.  I am hardly an "anti-nuclear activist", but I do think that we need some honesty about the problems with each technology, and every energy technology we currently know has problems.  What concerns me is that the "fan boys" of each technology have a tendency to downplay the problems with their favorite system - witness nuclear advocates playing down the side-effects of radiation because the effects are probabilistic, so scientific proof to a certainty is difficult (rather like it was for cigarettes), coal and oil advocates contending that global warming is a fraud, hydropower advocates ignoring the effects on fish and other parts of the water ecosystem, and so on. 
I think all of this is different from the anti-vaxers, who simply want everyone else to take risks and themselves to be free-riders.

Cuhulin wrote:

The real problem is not that the electricity comes from coal; it's that the coal-fired plants are from a 19th century coal infrastructure that was developed without regard to environmental issues.

While we've indeed gotten better at scrubbing particulate emissions, sulfur dioxide, etc., I'm not convinced that CO2 capture is viable over the long term.

Cuhulin wrote:

I think your math was about the side of the problem that definitely favors nuclear.  The problem with nuclear is at the waste end, in several different ways.  I am hardly an "anti-nuclear activist", but I do think that we need some honesty about the problems with each technology, and every energy technology we currently know has problems.  What concerns me is that the "fan boys" of each technology have a tendency to downplay the problems with their favorite system - witness nuclear advocates playing down the side-effects of radiation because the effects are probabilistic, so scientific proof to a certainty is difficult (rather like it was for cigarettes), coal and oil advocates contending that global warming is a fraud, hydropower advocates ignoring the effects on fish and other parts of the water ecosystem, and so on.

Yes, nuclear has issues too. I tend to think it is the lesser among multiple evils as a transitional solution though. I don't think it is a good long-term solution (unless practical and clean fusion tech becomes viable), but I think it is a good stopgap to ease the transition away from fossil fuels.
 

Cuhulin wrote:

I think all of this is different from the anti-vaxers, who simply want everyone else to take risks and themselves to be free-riders.

It's still a case of "this doesn't have direct and immediate negative impacts on me, so it is someone else's problem".

***

We can continue this tangent in R&P if you'd like.

In most European, Japanese and Russian reactors, the spent uranium is reprocessed to be used again. A reactor typically generates about 3 cubic meters of high-level radioactive waste per year. This stuff is encapsulated in borosilicate resin and stored in a glorified swimming pool for 40-50 years at which point it is effectively safe. It's still radioactive but can be safely buried in the ground with no risk, since there are natural granite outcrops that pose a greater radiation risk to life than this waste when buried.

So, the "worst part" about nuclear waste is that you have to finance a fancy swimming pool for half a century to store this stuff in a safe manner until it has decayed enough to be considered safe to bury. After 18 months it has already lost something like 90% of its radioactivity and is moved to a secondary pool that requires no active cooling. Were this pool to suffer some kind of earthquake-induced disastrous failure and require the waste to be buried there and then, it could be entombed in concrete and the exclusion zone (if one were needed) would be limited to the site, possibly even to just the building that housed the pool in the first place - and only for a couple of decades.

No matter how many scare stories are floating around because of anti-nuclear campaigners talking about the dark old days of mismanaged waste and accidents like Chernobyl, modern nuclear waste is practically a non-issue compared to the obsolete nuclear plants from the prior millennium. It's like telling someone not to get into a dangerous car because the fuel will explode, when in fact the percentage of deaths caused by vehicle fuel explosions is so negligible compared to more realistic issues that people would look at you like some kind of loony for even considering it in the first place.

viewtopic.php?f=1&t=118473

 

cheesyking wrote:

Frugal wrote:

But let's talk about gas tanks.  People who like EVs seem to make them out to be extreme fire hazards but the reality of what it takes to cause a gas tank fire is very very uncommon and usually can be traced back to negligence of the operator or things like 60 mph rear end collisions.

It is probably more common to get burned sending smoke signals but I still think cell phones shouldn't catch on fire.

As long as EVs keep catching on fire, it is a problem.

There are quite a lot of fires while putting the petrol in the car, on average about 3000 a year in the US with 2 fatalities. Sure you can put this down to idiocy and the pumps in the US not requiring you to hold on to them while filling but you're kidding yourself if you think petrol is safe.

Of course current batteries aren't safe either and charging an EV overnight in a garage attached to your house could end badly.

With a proper fuel filler and pump nozzle, it's safer to refill hands off, a lot of fires go from minor to horrible when a motorist holding the nozzle pulls it out while it is still pumping and it becomes a flamethrower.  Also, if a motorist just starts the pump and steps away, they have removed most of the common ignition sources (static electricity) that cause refueling fires.
Is Gasoline safe?  I think so.  The risks are minor and easy to mitigate.  They are also risks that the motoring public is accustomed to.
Are EVs safe?  They might be safer from a fire standpoint but they do not share the same perception as a gasoline automobile and people buying a Tesla don't want any chance of fire even if it is a small one.  I'm still not convinced that EVs will prove to burn up less than ICVs once they become common and the average age of the fleet starts to approach that of ICVs.
Garage fires are a big deal and when cars are designed to wait for off peak hours to start their charge (when people are asleep or just generally not paying attention), bad things will probably happen.  Charging rate doesn't have much to do with it because modern EVs and chargers are designed to limit the current to a safe level but a compromised battery or current limiting circuitry could lead to a problem.  Since EVs get charged every day and some times several times a day, the chance is higher than an ICV that might refuel once a week.

Frugal wrote:

With a proper fuel filler and pump nozzle, it's safer to refill hands off, a lot of fires go from minor to horrible when a motorist holding the nozzle pulls it out while it is still pumping and it becomes a flamethrower.  Also, if a motorist just starts the pump and steps away, they have removed most of the common ignition sources (static electricity) that cause refueling fires.

Incorrect! There is no differential charge accumulation as long as the motorist is holding the gas nozzle. The static discharge which ignites the fumes results when the motorist turns their attention elsewhere, then returns to the pump handle after accumulating a charge.  There has been some research into this and the majority of gas station fires are caused by younger women, for three reasons:

1) Women are more likely than men to return to the vehicle cab while the car is fueling;
2) Women's fashion tends to favor polyester and similar synthetics which readily build charge across the synthetic seat upholstery;
3) Younger persons tend to exit the vehicle without grabbing the door or frame for support, hence never equalize the static charge before returning to the pump.

Other than requiring the user to hold the fuel nozzle, there's a second way to deal with this: require a vapor-recovery hood and dripless anti-siphoning device on the pump nozzle, as is done in California.  I have mixed feelings on adding the extra cost to the pump hardware, given that retail gasoline is such a marginal business already, but I have noted that gas station bays in southern California are extremely clean and odor-free, so the devices seem to work very well.

Being a Californian, I don't know anything else.

In the grand scheme of things, I think vapor recovery gas pump nozzles are a very small price to pay (probably a fraction of a penny per gallon) and gasoline sales hardly seem like a marginal business.  The oil companies might say different but take a look at their quarterly reports to see how much they are hurting...

In California we have to pay for things like really high taxes and reformulated gas which added MTBE, then they reformulated it again to remove the MTBE which cost more again (and reformulated gas also causes fuel lines to melt on older cars causing fires).  Finally since we have oddball gas, when a refinery that makes California gas get shut down, our gas prices spike.  The oil companies are never in a hurry to get them back on line either...

No matter what happens, oil companies always price their gas to make a profit.

As an aside... the Chicago area required vapor recovery nozzles until a couple of years ago. But now the Illinois EPA has reversed this, and they must be removed by the end of this year:

http://www.illinois.gov/dceo/smallbizas ... lendar.pdf

It was a federal change announced back in 2012, because most vehicles on the road have onboard vapor recovery systems so having it on the pump is mostly redundant. This eventuality was more or less envisioned by the original Clean Air Act.

https://www.federalregister.gov/article ... -ii-waiver

Of course, states can continue to require them if they so desire, and CA has no plans to change.

I find it slightly odd that they are REQUIRING their removal here in IL. I wonder what the logic behind this is? Make-work program for the contractors licensed to remove the vapor recovery hardware?

Frugal wrote:

The oil companies are never in a hurry to get them back on line either...

I'm sorry, do you want them to hurry? I assume you're talking about Torrance, and that's down because it exploded, if you might remember...?

Frugal wrote:

No matter what happens, oil companies always price their gas to make a profit.

As opposed to...?

JBI wrote:

I find it slightly odd that they are REQUIRING their removal here in IL. I wonder what the logic behind this is? Make-work program for the contractors licensed to remove the vapor recovery hardware?

Certainly seems to be, they are very insistent that it has to be done by duly-licensed contractors and that all the paperwork must be in order.

Frugal wrote:

Charging rate doesn't have much to do with it because modern EVs and chargers are designed to limit the current to a safe level but a compromised battery or current limiting circuitry could lead to a problem.

It does still matter. "Safe charge speed" means something the manufacturer has determined to be acceptably safe. As you've been saying, it doesn't mean 100% safe (as nothing ever is). That leaves plenty of room for 0.2C (overnight) to be safer than 2C (< 1hr).

Generally any time this would be an issue, it's because the battery is already somehow compromised, but a battery has to be a lot more compromised to catch fire at 0.2C than 2C. Current limiting circuitry is a highly failsafed and extremely reliable part of the system.

Frugal wrote:

In the grand scheme of things, I think vapor recovery gas pump nozzles are a very small price to pay (probably a fraction of a penny per gallon) and gasoline sales hardly seem like a marginal business.  The oil companies might say different but take a look at their quarterly reports to see how much they are hurting...

I included the word "retail" because the gasoline sold at the pump has been, in the US at least, a marginal business.  The attached convenience store is what pays for the actual facility and cashier(s) while the gas just pays for itself. Although it is technically possible to run a corporate or even "headless" gas station (and there are some out there), pushing everyone to do so through additional regulatory hurdles just kicks another rung out of the small business ladder that many people (immigrants in particular) rely upon to become established in the US economy.

cheesyking wrote:

There are quite a lot of fires while putting the petrol in the car, on average about 3000 a year in the US with 2 fatalities. Sure you can put this down to idiocy and the pumps in the US not requiring you to hold on to them while filling but you're kidding yourself if you think petrol is safe.

3000 fires out of how many fueling instances? Tens or hundreds of millions? At this rate ladders are more dangerous. Petrol does have its hazards but I think filling the tank of your car is pretty safe.

Glorious wrote:

Frugal wrote:

The oil companies are never in a hurry to get them back on line either...

I'm sorry, do you want them to hurry? I assume you're talking about Torrance, and that's down because it exploded, if  you might remember...?

Frugal wrote:

No matter what happens, oil companies always price their gas to make a profit.

As opposed to...?  :roll:

Yes, they should hurry and there is also the Richmond refinery which keeps catching on fire.  The key here is that the refineries are mis-managed and broken down which is why they go off line.  In the rest of the country where refineries go down and it doesn't cause a blip because other refineries take up the slack, they repair them quickly and properly because they don't want to lose money.  Evidently there is a different economic force at work in California.
My point about gasoline pricing is that the oil companies don't care what happens, they use everything as an excuse to raise prices and they never have to bear any of the hardship that they created.
In every other competitive industry market forces push prices downward for the most part except for real shortages and when things like the plastic plant burned down and made DRAM prices spike, they hurried to get the situation resolved.