PWM shunt regulator

Do you have any evidence for that? ...or should all experiments that don't give the results you agree with be dismissed as propaganda?

A wise man adapts his ideas to take account of reality

Your analogy is completely false.

They initiated the fire with a nail, so that they could be certain of the starting time. They could equally well have initiated it by over-charging the battery but the exact start of the process would have been uncertain. If you wanted to study the spread of fire from a petrol tank, you would need to initiate the reaction by some intervention that rarely occurred in practice - but it wouldn't mean that measurements taken on the subsequent events weren't valid.

It won't catch fire. You can search for this yourself:

bullet gasoline tank fire

It's a myth, mainly as a result of many Hollywood movies showing cars exploding from a single bullet to the tank. Even multiple bullets fired into a tank won't cause the fuel to ignite. You need an incendiary bullet, and even then you might require more than one.

Given trouble due to CO2 and movement to electricity, I wonder why nobody is talking about electrolysis of CO2? Clearly there are technical difficulties, starting from fact that in normal conditions CO2 is a gas. But is it hopeless?

I'm sure that you like to think that. That doesn't make it true.

"They could have equally well ..." is a dubious assertion. A nail is a much bigger object than a dendrite, and can carry a lot more current before it comes apart.

Setting up and initiating event that is guaranteed to dissipate a lot of energy in the separator does makes sure the the fire does take hold, but does mess up a lot more of the battery than a more realistic initiating event would have done.

Petrol tanks are much simpler objects than batteries of electrolytic cells.

Your researchers probably initiated a different kind of "fire" from the one you get if you cycle a battery to the point where the self-discharge is high enough to get you into thermal runaway. That would have taken quite a while, but the results would have been a lot more relevant, if perhaps less useful to the fossil carbon extraction industry.

And there are people who insist that their fuel tanks won't self-ignite if a bullet goes through them - they make military aircraft.

It's easy to get rid of CO2: feed it to plants.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

We (the good guys) got a great advantage in WWII, with planes that had self-sealing gas tanks. And armor to protect pilots.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

The insurance statistics talk about the chance of single car catching fire. More cars may mean more reliable statistics, but doesn't change the probability of a single car catching fire.

The insurance statistics do include the age of the car. If older cars did catch fire more often they would have noticed it, and jacked up the premiums. The car I drive was bought fifteen years ago, and the insurance premiums haven't gone up

The fires may originate in the electrics, but most electrical faults don't start a fire. The problems with internal combustion cars mostly come when the fire manages to ignite the fuel tank. The batteries in electric cars do seem to be harder to ignite.

A perfectly splendid program. Have you worked through it with real statistics?

There's a whole insurance industry that has been doing that for years. They hire actuaries to do it. You aren't an actuary.

I'm sure that you think that you sound like an actuary. You don't.

I think you will find the Germans had them before WWII broke out but we didn't develop them until later. Apparently the UK research was bogged down by mission drift or 'specification-runaway'.

Is that an electric car (the type of car we are talking about)? If not, what is the relevance of your insurance premiums to the safety of electric cars?

You made the original assertion, not me. The onus is on you to prove it.

You can certainly compress CO2 to make it into quite a dense fluid.

Getting that fluid to conduct electricity seems to be difficult.

The aim would be to get oxygen diffusing out of one electrode and carbon

- presumably graphite - depositing on the other.

A less ambitious target would be to get carbon monoxide at one electrode and oxygen at the other

My guess would be that it is hopeless.

Not all that easy. There are greenhouses in the Netherlands where the atmospheric CO2 level is kept high. The plants need to be well lit to capture it by photosynthesis, as well as well watered and well fertilised. It's not cheap, and the out of season produce you get needs to sell at premium prices.

It's a bit more complicated than that. A half-full gas tank contains a potentially flamable mixture of hydrocarbon vapour and air. There is gear that extracts 99% pure nitrogen from air which you can use to lightly pressurize the tank. Modern aircraft use it.

Operations research on WW2 bomber losses took a while to work that this was a useful trick.

A single bullet may not always ignite a gas tank, but it happened often enough over Germany in WW2 to take down quite a few bombers.

We burn carbon - combine it with oxygen - to make energy.

It would take more energy - several times as much - to separate the carbon from the oxygen.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

They would have been brought down by cannon shells (20mm shells containing a small high-explosive charge), not bullets, which were highly inefficient:

(from

ME 109s were fitted with 20mm cannon, and in late 1943 the variant Bf

Old cars had gas gauges that used a float and a wirewould pot, inside the tank. It didn't blow up because the mix in the tank wasn't flammible.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

an the fuel pump is submerged in the gasoline

It's not an electric car - the fact that my wife and I bought it fifteen years ago should have made that clear. The relevance was to your implicit and unsupported claim that older cars were more likely to catch fire.

Which original assertion was that? As debating tricks go, that's an old one, but not a good one.

John Larkin never paid much attention to his chemistry lectures.

The amount of energy required to separate the carbon from the oxygen in carbon dioxide is exactly the same as the amount of energy released when they recombine.

There would be other losses in any process that separated the carbon from the oxygen, so you have to put extra energy to get it to happen, and while the process of letting carbon burn to carbon dioxide does generate energy, you can't capture all that energy - thermodynamics was invented to keep track of the losses.

I didn't get exposed to thermodynamics until the second year of my chemistry course and it's a notoriously difficult subject to teach. John Larkin may not even know that the he doesn't known anything about it.

Wrong. The mix of air and gasoline vapour inside the gas tank can be flammable. The wires inside a wirewound pot never got hot enough to ignite the mix. If you every been exposed to "intrinsically safe" electronic design you'd be aware of this.