Hydrogen

[Thunderchild]

Oh dear. "carbon burns into energy?" Destroying a carbon atom by burning it?

Energy is in the bonding between different elements within compound. Breaking up and forming bonds either take up or releasing energy. That's what I've been taught while I was a small child.

Don't they teach this in school anymore?

OK granted I might have made a mistake there I see your point but still there's nothing wrong with burning H instead. whether or not CO2 or CO (anything that we don't normally breath) is dangerous or not is besides the point the fact that we are creating large amounts of it which is causing global warming and into the bargain making more heat for it to confine. as i said before the earth long before we were around was in a state of global warming and apart from the natural cooling of the earth trees and plants absorbed the excess CO/CO2 and then died and storing it in the form of fossil fuels, then we come along and let all that carbon out again taking the earth back to what it once was

 

[eblc1388]

No one is opposing the use of hydrogen. Don't be fooled, it all come back down to cost. It is my impression that burning hydrogen to obtain energy is a false economy.

It is always the case(up to present year 2007) where more energy input is required to get the amount of hydrogen which then burns to produce some energy. It is always less than one started or puts in the first place.

If one can obtain hydrogen cheaper than other fuels(maybe in the future), then by all means use it.

 

[Thunderchild]

well what do we do now ? we burn 4 KW of fossil fuel and only get 1 KW of electricity out of it, it is more economical and environmentally friendly to use gas for heating rather than electric at least it is 100 % efficient, think how stupid we use 4 KW to make 1 KW so 3 KW go out in heat anyway then we make heat out of the remaining 1 KW to heat our homes and cook how silly.

 

[mechie]

Power to the people

well what do we do now ? we burn 4 KW of fossil fuel and only get 1 KW of electricity out of it, it is more economical and environmentally friendly to use gas for heating rather than electric at least it is 100 % efficient, think how stupid we use 4 KW to make 1 KW so 3 KW go out in heat anyway then we make heat out of the remaining 1 KW to heat our homes and cook how silly.

Actually, modern power stations are over 50% efficient so we use 2kW of fuel to generate 1kW of electricity.
If only industry were as efficient as a domestic central heating system ... 100% ? NOPE !
I'm afraid life isn't that simple - energy conversion is just one aspect of the argument - pollution is another, I suspect a modern power station produces far less pollution than a domestic cooker (per unit of fuel consumed). If you look into a process called 'flame impingement' - anybody that services gas appliances should know of this - it causes CO emissions to increase signifiantly, along with NOx --- and they are both unhealthy to breathe. Flame impingement is where a flame touches a surface such as your cooking pan.

 

[bloody-orc]

What happens when you start to burn H2 instead of C8H18 (most common element in petrol). Well... you get a BIG BANG and water vapor (H20). H2 burns over 50 times faster than any ingredient in petrol. To burn one unit of C8H18, you need 21 units of O2. And you say, it doesn't use a lot of Oxygen... check your facts before you say anything. CO2 isn't harmful most cases. But put it together with H2O (water) and you get H2CO3, witch is acid. Pretty strong one actually. In Petrol there is also some S8 So it too burns and takes some O2's creating SO2, witch also reacts with water to make H2SO3, one of the lowest pH levels.

2C8H18*S8+41O2->16CO2+18H2O+16SO2



There are many safer and more energy efficient ways to make H2 IMHO. Take Alkali metals or Alkaline earth metals, add some water and BOOM you got some H2.
Or metal + acid -> salt + H2
etc.

you could also make some NO2. One of the byproducts of this is H2. But I'm not going to give the formula here. just in case.


--Rain--

PS Chemistry exam coming soon

 

[Pommie]

CO2 isn't harmful most cases. But put it together with H2O (water) and you get H2CO3, witch is acid. Pretty strong one actually.

That would be why carbonated drinks rot your stomach.

PS Chemistry exam coming soon

Good luck.

Mike.

 

[bloody-orc]

Sry got one fact wrong. H2CO3 is an acid, but turns into H2O and CO2 fairly quickly (1.75ns approx). Only H2S is weaker (also alcohols and other organic Acids). And it is pretty neutral acid also. H2SO3 and H2SO4 in the other hand are VERY strong acids so one should better avoid them

 

[Thunderchild]

well by spliting water you also produce the oxygen that will be used to burn the hydrogen, if electrolysis is so inefficient then the water would boil or some thing as the excess energy must be turned into something useless and that's normally heat

 

[Thunderchild]

Dear all being rather p!ssed at undue criticism (yes I now have the proof that is it undue) I researched, this comes from the wikipedia:


"The energy efficiency of water electrolysis varies widely. Some report 50–70%[1], while others report 80–94%.[2] These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included."


yes there is the efficiency of the electricity plant to consider but I still feel that it could be somewhat competitive,
consider right now we are paying a lot of money for fossil fuels to make our electricity and a power plant is only 25-30 % efficient and VERY poluting. now solar panels are 25 % efficient and electrolysis is reported as being AT LEAST 50 % efficient, so that is 12.5 % total efficiency against 25-30 % but for the comecial side of it a solar panel will make MW of power in it's life time and costs nothing to run but for our tradtional methods we have to mine the fuel, possibly refine it then transport it and as the machinery is all mechanical it needs constant repair throughout its life time, so there you go

 

[mneary]

I would like to see your maintenance free solar cells after a sandstorm. And as for your maintenance-free hydrogen pipelines, YOU can live next to one.

 

[Thunderchild]

well we already have methane pipelines so why can't we have hydrogen pipes and as I said the two gasses can be fed down the same main pipe, Aren't there lots of people in Africa that need a means of survival, surly people could be employed to keep the panels clean you could even put a wind screen wiper system on them haha, don't our current power stations require people to run them ? often highly paid technicians

 

[bloody-orc]

One thing is creating H2, Other thing is carrying it. The damn bastards leaks very well. also, what happens when two cars think, they should crash... gasoline + one spark = nothing. Gasoline needs flame to start burning (vapors is another matter here, I'm not talking about that). But H2! light a match 100m away and WOOSH! half of the town is clean. Haven't you done experiments in your chemistry class


I'm not saying that petrol ruulz or anything. I'm personally against petrol myself; but I don't see H2 as an alternative (at least not in the near future). There are some a lot more convenient ways to propel the 4 wheeled machine by the road. I use 2 wheels and bone-power. Hey someone even made a car, that ran on piles of poo. even human one!

I see electricity a better option. Of-course I know those batteries weigh a ton, but for how long? LiPo's weigh less than the wires connecting it to the LED

 

[Thunderchild]

I persoanlly use the two wheeled vehicule powered by my own mucles as well, there is of course the posibbility of carrying the electricity straight over to europe in cables and distributing it but I don't know how feasable that is we would be talking very high voltages can they be put under the sea ?

 

[bloody-orc]

No cables are VERY bad. the cable from Tallinn to Helsinki (90 minute drive on boat) cost a few billion euros IIRC. That's a lot as you probably know. And to carry Hydrogen... even worse idea. ever heard about zeppelins? 1:10 urned in violent flames killing 99% of passengers.

 

[Nigel Goodwin]

Dear all being rather p!ssed at undue criticism (yes I now have the proof that is it undue) I researched, this comes from the wikipedia:


"The energy efficiency of water electrolysis varies widely. Some report 50–70%[1], while others report 80–94%.[2] These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included."

Try reading the other links I posted, or do a simple google - there's LOT'S of sites saying it's too inefficient to be of any use, and even giving schemes to make it more efficient - and if large scale solar panels were of any use (compared to other sources) they would already be widespread!

 

[bloody-orc]

The chemicals needed to make the solar panel cost a LOT right now. researchers are developing new ways to do the panels, but it's still a working progress.

 

[Pommie]

The biggest problem with hydrogen is it isn't easy to liquefy. LPG is liquid at about 40psi and can be stored in a relatively light container. Liquid Hydrogen cannot be stored at STP and so is stored as a highly compressed gas at around 5000psi. This requires a very heavy container that is a potential bomb. It also takes a large amount of energy to compress the gas. Hydrogen is also not a very good fuel, it takes about 3 liters of liquid hydrogen to produce the same energy as 1 liter of petrol.

One day soon, someone will find a method to turn energy into hydrocarbons and all our problems will be solved. Here in Aus we could put a few nuclear plants in the outback and churn out petrol equivalent all day long. We could even have solar powered stations if the only energy required is in the form of heat.

Mike.

 

[Oznog]

The shame is that California's EV mandate was turning out some very promising battery-electric vehicles, then they got the guy appointed chairman of the commitee and got the mandate changed to include hydrogen fuel cells the mfgs discontinued their EV programs that very day.

Nothing against hydrogen, it's not hydrogen's fault, it's that is was used to kill the functioning EV programs with this hydrogen plan where the mfgs won't end up having to do anything at all, effectively nullifying the whole concept. Mfgs can just keep pointing out "the technology is not ready" as their excuse each year.

 

[mneary]

The thing that I have against hydrogen is that it's only an energy transport medium (and not a very good one). It's not an energy source.

It's distracting to the naive who should be looking for improvements or replacements to our sources of energy.

 

[Rolf]

"No cables are VERY bad."

No cables are VERY bad. the cable from Tallinn to Helsinki (90 minute drive on boat) cost a few billion euros IIRC. That's a lot as you probably know. And to carry Hydrogen... even worse idea. ever heard about zeppelins? 1:10 urned in violent flames killing 99% of passengers.

Maybe you should read this:
https://search.abb.com/library/ABBL...LanguageCode=en&DocumentPartID=&Action=Launch

According to the latest investigation of the zeppelin tragedy, they found that a major cause was that the dope (paint) the Germans used, was a mixture of iron oxide and aluminum powder, it was just a little flammable and set off by lightning in the tail away from the hydrogen gas bags. Of cause the Germans kept this a secret during the investigation that followed.
All this was exposed in a very interesting PBS program not long ago.