Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

 Haighus wrote:
I wonder how they have solved the issues of pressurising hydrogen and also safety when driving round a tank full of pressurised hydrogen.

They haven't exactly solved the issue of having a tank of gasoline - or worse, a tank of gasoline vapor - yet. We still get gas-powered cars catching fire even today. Granted, it's fairly rare, but it still happens.

 Vulcan wrote:

 Haighus wrote:
I wonder how they have solved the issues of pressurising hydrogen and also safety when driving round a tank full of pressurised hydrogen.

They haven't exactly solved the issue of having a tank of gasoline - or worse, a tank of gasoline vapor - yet. We still get gas-powered cars catching fire even today. Granted, it's fairly rare, but it still happens.

A petrol fire is manageable though, and petrol explosions are extremely rare. A pressurised hydrogen tank is liable to explode much easier.

no its not, a gasoline tanks is still more dangerous, as fire and to explode than a hydrogen tank

for hydrogen to explode, there need to be the right temperature and the right amount of oxygen

a hydrogen tank exploding looks like this:

More likely to get a vent valve fire rather than an explosion.

Recent UK stats indicate about 300 cars catch fire every day here. That’s still quite a lot, but as a fraction of all existing vehicles is quite low.

 kodos wrote:
no its not, a gasoline tanks is still more dangerous, as fire and to explode than a hydrogen tank

for hydrogen to explode, there need to be the right temperature and the right amount of oxygen

a hydrogen tank exploding looks like this:

What does it look like if it happens at an 80mph impact or 160mph impact (relative when head on from two 80mph vehicles) instead of falling over? The former is what you might see with an automobile collision.

I’m not sure that whatever comes after the crash is going to make much difference to any of the people involved i. Ahead on crash of combined 160mph

basically the same, as to explode it you need the necessary energy and oxygen mix

the same way gasoline does not explode on a car crash, as for the explosion the mixture need to be right
hydrogen will burn if ignited but not explode

what people think of is Oxyhydrogen, a gas were hydrogen and oxygen are already mixed and this will easily explode if under pressure (under normal pressure there won't be an explosion)

this is usually what is seen in experiments with balloons filled with gas and ignited, but there is already an explosive mix under pressure inside the balloon
if the mix is formed outside the tank, it won't explode because it is not under pressure any more, and inside the tank there is no oxygen

Also a single loose gas bottle that's designed to do what that video showed is a little different from one strapped or built-in to a moving vehicle. Pressure explosions can be every bit as nasty as chemical ones.

Hydrogen ignites much much more readily than gasoline fumes though, and since it also requires a pressure tank the combo is a bad one.

A gas tank that gets penetrated might or might not ignite, but relatively speaking it will burn much more slowly if it does. And if it doesn't ignite its not going to hurt anybody. A hydrogen tank that gets violently disassembled is going to explode even if it doesn't ignite, and it is much more likely to ignite in the first place.

The thing you have to remember is that if cars didn’t already exist there is no way they would be allowed on the roads as a new invention.

“We’ve designed this metal box to transport people from place to place. It will be capable of moving at twice the legal speed limit (four times in urban areas), with no restrictions other than what the operator chooses to do, its powered by highly flammable and/or explosive gasoline and emits a whole load of particulates and chemicals that cause severe respiratory problems (plus a bunch of CO2). Oh and anyone will be allowed to operate one for their entire life, following a single, basic and generic, training course when they are a teenager.”

“Get out.”

Some interesting experiment and testing and clevers and that from the world of air freight.

https://www.bbc.co.uk/news/articles/c0kk4lxe702o

 Skinnereal wrote:
I am sure the holes in the ground from mining battery bits are just as big

Quite a few mining companies are keen on getting in on the Brine business to get lithium.

 Jadenim wrote:
The thing you have to remember is that if cars didn’t already exist there is no way they would be allowed on the roads as a new invention.

“We’ve designed this metal box to transport people from place to place. It will be capable of moving at twice the legal speed limit (four times in urban areas), with no restrictions other than what the operator chooses to do, its powered by highly flammable and/or explosive gasoline and emits a whole load of particulates and chemicals that cause severe respiratory problems (plus a bunch of CO2). Oh and anyone will be allowed to operate one for their entire life, following a single, basic and generic, training course when they are a teenager.”

“Get out.”

The thing is not only did cars evolve over time but society evolved to rely on them.

We now rely on cars very heavily as a society unless you live in a modern urbanised environment. Otherwise lots of bus and train services in the countryside are gone (UK side even masses of track pulled up post-war). The Pandemic actually made home delivery more viable to survive on; but at the same time that still relies on the car (Vans). Take away cars and the whole infrastructure would need to be rebuilt from the ground up. There'd also be a lot of life-expectations that would have to change or adjust too.

Safety features also evolved.

Consider the “not being squished” as a car passenger or drive chances, and how whilst far from idiot proof, they’ve become ever less riskier to drive.

No one innovation makes a particularly significant difference. But…ABS, three point seatbelts, crumple zones, inbuilt roll cage type things, collision detection sensors and so on and so forth all, step by step, combine to make driving pretty safe. The same with engine and fuel safety and that.

As my Grannies despite being Scottish never to the best of my recollection actually said? Many a mickle mak’s a muckle.

 Haighus wrote:

 kodos wrote:
no its not, a gasoline tanks is still more dangerous, as fire and to explode than a hydrogen tank

for hydrogen to explode, there need to be the right temperature and the right amount of oxygen

a hydrogen tank exploding looks like this:

What does it look like if it happens at an 80mph impact or 160mph impact (relative when head on from two 80mph vehicles) instead of falling over? The former is what you might see with an automobile collision.

If there's a head-on collision at 80 mph each, I doubt it's going to matter to what's left of anyone in either car whether the cars are powered by gas, hydrogen, or lithium ion batteries.

 Jadenim wrote:
The thing you have to remember is that if cars didn’t already exist there is no way they would be allowed on the roads as a new invention.

“We’ve designed this metal box to transport people from place to place. It will be capable of moving at twice the legal speed limit (four times in urban areas), with no restrictions other than what the operator chooses to do, its powered by highly flammable and/or explosive gasoline and emits a whole load of particulates and chemicals that cause severe respiratory problems (plus a bunch of CO2). Oh and anyone will be allowed to operate one for their entire life, following a single, basic and generic, training course when they are a teenager.”

“Get out.”

While a cute modern take on the subject, I do have to say this is wrong. Cars didn't just appear ex-nihilo, nor was what they offered a new thing. They were a new way to do something people were already doing.

Horse carriages, or just riding horses, and wagons good sir. Cars weren't a new thing, they were an upgrade on an old thing.

And the coming of cars actually is what saved our cities from the old chaotic mess that was street traffic back in the day. It forced us to come up with codified rules for street traffic, separating pedestrians and vehicles, making sure vehicles operate in designated lanes with right of ways. We didn't have much of that at all back with the old horse and buggies.

And as for pollution. Show anybody from the turn of the century how clean the air is today compared to back then and they won't believe car pollution could possibly be a problem. Cities at the time were universally living under palls of soot and smog that makes the worst day in modern LA look positively clear.

Apologies guys, I don’t think my point came across, it wasn’t an anti-car rant (although I’m a big supporter of better public transport and urban design*), it was just that you can’t compare new technologies such as hydrogen with the existing technology, because the barriers to entry are much, much higher now.

Essentially existing internal combustion vehicles have an unfair advantage as a legacy technology that has embedded itself over a century, but that when looked at in the cold light of day would not meet modern expectations around safety, sustainability etc. that new technologies have to.


Automatically Appended Next Post:
You can make similar arguments about other things; railway stations for example. The only thing stopping me putting a body part in front of several hundred tonnes of metal going at 100mph is a little yellow line on the platform. And they only introduced that in the last couple of decades.

James May talked about this in a series he did a few years ago when he looked at stuff like flying cars, personal jet packs, etc. Even if you can get the technology working, the regulatory hurdles will just kill most ideas. At a fundamental level, most of our transport systems (and probably infrastructure) are essentially 19th century technologies, because they got embedded before our attitude to regulation changed.

Edit: * not that I’m suggesting anything stupid like “ban all personal vehicles”, just that there are better solutions in a lot of cases, if you invest in them.

New dangerous ways to transport yourself have been invented, they are often just super expensive and niche or situationally restricted enough that they aren't mainstream.

Just look at rocketships!



Lets face it the real barrier isn't legislation, its cost. The reason we don't have flying cars is that they cost a LOT more. They cost more to buy, more to run, more to train for to use. They also cost more to build infrastructure for since most people don't have a mansion with a runway at home and major road networks don't have runways on them either.
So you need very affordable, very cheap, easy to use equipment to break onto the market and there's just not the transport pressure there for a firm to have made it work.

You get the odd "rich toy" developed here and there because that's basically what they are. You also need a firm willing to push hard and spend years in the "rich toy" market to develop technology, manufacture and infrastructure to a point where there is a chance for uptake. Sometimes this relies on other technologies catching up and getting cheaper.
Look at VR. It's been around since the 90s, but its only now that its actually starting to carve our an actual viable mass-market to itself and growing. It took home computers getting more powerful; components coming down in price and a bunch of other things including firms wiling to invest and push it to make it happen.








And yet at the same time we have things like Mountain Rescue starting to look at seriously using jetpacks for rescue work.
We have Amazon wanting to do drone home delivery, which you can be sure if they can get it to work will continue to upscale it to larger and larger drones and packages being shipped around.


I don't think its legislation that stopped it all; but I will agree that legislation can slow down or restrict development; but the biggest barrier is having a pathway to a big enough market to make a big change.

I'm sure people argued similar about cars - a massive fundamental change in personal transport over horses and foot and train. It took ages and ages for cars to be affordable enough for mass market changes; the legislation sometimes ahead but limiting (flag walkers in front) and periods where it was way behind the faster uptake of cars.

Legislation can either get left behind and things change before laws are forced to adapt (see things like escooter rentals or Uber operating even though both are either illegal under some existing laws; or aren't covered specifically); or it can hold things back and slow them down.

In general it only stops things if its specifically setup against things. Otherwise if there's money to be made ...

 Grey Templar wrote:


And the coming of cars actually is what saved our cities from the old chaotic mess that was street traffic back in the day. It forced us to come up with codified rules for street traffic, separating pedestrians and vehicles, making sure vehicles operate in designated lanes with right of ways. We didn't have much of that at all back with the old horse and buggies.

Well, cars are far more dangerous than horse and carts, so it makes sense it wasn't needed prior. The same effect was already happening due to trains, which is why most of the elevated lines were built in US cities.

It had consequences too- rather than being grade separated like trains, cars took over public spaces that used to be built around people. This has had both positive and negative effects, and there is a rebalancing happening in much of the developed world where urban centres are being pedestrianised again with cars limited to the outer areas where they are more beneficial.

And as for pollution. Show anybody from the turn of the century how clean the air is today compared to back then and they won't believe car pollution could possibly be a problem. Cities at the time were universally living under palls of soot and smog that makes the worst day in modern LA look positively clear.

Car pollution used to have lead in it, which is a plausible theory for why violent crime used to be so much higher Visible pollution isn't necessarily worse for you than the hidden stuff.

 Haighus wrote:

Car pollution used to have lead in it, which is a plausible theory for why violent crime used to be so much higher Visible pollution isn't necessarily worse for you than the hidden stuff.

Depends. Visible pollution tends to kill you before the invisible stuff can kill you. You won't live long enough to develop cancer if you're inhaling coal dust every day of your life. Lead poisoning is also one of those hard to interpret issues, it doesn't actually kill you(at least not unless its at stupid high levels), it amplifies existing behaviors, and it was combined with a lot of other changing variables. Like simply more people living in more and more crowded cities at the same time as massed lead gasoline exposure. So was it the lead in the air, general pollution, or people being packed together, or a combination of it all together?

Remember that back in the 1800s cities actually had negative birth rates, mostly down to the pollution. People died faster than they were born and the population only kept steady because of the influx of peasants coming from the countryside looking for work.

Now that the absolutely worst pollution has been curbed in modern cities, we are now dealing with the longer term stuff that takes your whole life to kill you.

Being old enough to remember roads before Unleaded Petrol really kicked in? Leaded Petrol has a very specific exhaust smell.

I couldn’t describe it to you right now, because it’s been decades and my scent memory isn’t that good. But I could 100% tell you if a vehicle using leaded petrol drove past.

And being born in Edinburgh, there are still buildings there covered in soot from when the city really earned the nickname Auld Reekie.

https://www.bbc.co.uk/news/articles/czxl849j77ko.amp

This is a cool one simply because water on Mars has been a staple of sci-fi since forever.

Also would love a journey to the centre of Mars where all the life on the red planet is 20km deep beneath the surface.

It is super cool news. I will basically be imagining this from now on:



Probably need quite a big spade to get down there though.

Nah I'm good. I saw Waters of Mars and I'm fine not having water zombies thanks.

 Gert wrote:
Nah I'm good. I saw Waters of Mars and I'm fine not having water zombies thanks.

There were quite a few of the Tennant era Doctor Who episodes that were deliciously creepy and that was one of them.

I also saw an article about signs of life in Venus' atmosphere?

The discovery of a possible sign of life in Venus’ clouds sparked controversy. Now, scientists say they have more proof

https://www.cnn.com/2024/07/29/science/venus-gases-phosphine-ammonia/index.html

 Easy E wrote:
I also saw an article about signs of life in Venus' atmosphere?

The discovery of a possible sign of life in Venus’ clouds sparked controversy. Now, scientists say they have more proof

https://www.cnn.com/2024/07/29/science/venus-gases-phosphine-ammonia/index.html

Interesting. The bit about the time of day being required for the observations in particular, as a) it explains the discrepancy with the other studies but more importantly b) it would indicate a continuous process for the production of these chemicals.

Unfortunately, given that I’ve also heard that they’ve found active volcanoes on Venus, plus Venus’ generally high energy, active, atmosphere, I imagine that there’s an awful lot of geological and chemical processes that will need to be eliminated until you can say it’s a bio signature . As PBS SpaceTime is fond of saying “it’s never aliens, until it’s aliens.”

If, IF, it were shown to be extraterrestrial life, that would be very, very, exciting, because the chances of it being panspermia from Earth is very low, due to the extreme differences in environment and it would also open up a whole swathe of different potential places to look for life in the universe. In fact it could be very revealing in defining what life actually is and how it starts. Potentially much more useful than Mars or Europa, in fact.

I think I heard someone say they're walking it back already.

I thought it was an established fact that Venus was covered in deadly jungles inhabited by hot babes?

Next thing you know those so-called “scientists “ are going to tell us there are no canals on Mars and that Pluto isn’t a real planet.

Retro-pulp science is the only kind I want these days. Much more fun and evocative then this whole reality thing.

 Nevelon wrote:
I thought it was an established fact that Venus was covered in deadly jungles inhabited by hot babes?

Next thing you know those so-called “scientists “ are going to tell us there are no canals on Mars and that Pluto isn’t a real planet.

Retro-pulp science is the only kind I want these days. Much more fun and evocative then this whole reality thing.

Or possibly an endless ocean with floating islands... and hot green babe (just the one)