Jujupilote wrote:
Today Airbus announced several new projects of airliners burning hydrogen
I wonder what secrets they know that we don’t:
The problem with hydrogen, which isn’t going to be solved any time soon:
It is all nonsense, of course. Hydrogen might just possibly make sense if we had nuclear fusion (split seawater with “cheap” electricity).
It is the modern way of promoting a business, while preserving green credentials. Putting a team of a few people on a project to do some research might cost say €1M a year. And it buys you loads of green credibility. But buying advertising space in traditional media will cost much more and will buy you zero green credibility.
Everybody is doing this now.
In France right now this is a critical issue. Every big business is watching its 6 o’clock. Emitting the right sort of “social symbolism” is what it’s all about.
alioth wrote:
The problem with hydrogen, which isn’t going to be solved any time soon:it has to be stored at extremely high pressure, and the molecule is so small it leaks through the container you keep it in while at the same time embrittling it.
it is not very energy dense. Sure, it’s energy dense per kilogram, but per volume even under absurd pressures it’s not energy dense – unless you’re going to cryogenically store it which brings in a huge new raft of problems. Because your fuel tank now has to be at very high pressure, it has to be a cylinder, not simply the shape of the inside of a wing, which therefore will reduce the usable volume.
We had hydrogen buses running on trial in my hometown for a while so obviously these problems can be solved.
hydrogen is made from fossil fuels anyway. Electrolysis is tragically inefficient, so is generally not used to produce large quantities of hydrogen. Therefore, unless there’s some kind of technological breakthrough, you’re going to have lower total emissions just buring kerosene.
Electrolysis has the advantage that it can be done with electricity created on site by solar power.
Also in theory one of the best ways to produce hydrogen is to extract/convert it from methane, seen as one of the worst of the greenhouse gases and coming free with every cow:) or dog or human for that matter.
alioth wrote:
hydrogen is made from fossil fuels anyway.
Maybe it’s the same CO2 emission & pollution as the end of the day, but you have control on CO2 emission & pollution at one source rather than million sources at various user points, the later can be priced & solved, the former is impossible to sort or control !
It’s like electricity from nuclear power, it’s very clean as far as I am concerned using it 250nm away 
I had few doubts when I got few Sieverts in my film but I only spent 3months near the source 
Less fun if all cars in my street have PWR in their cowlings !
My research work is on direct splitting of water with sunlight using semiconductors. Spending my life writing grant applications while it’s a hot topic!
“Also in theory one of the best ways to produce hydrogen is to extract/convert it from methane, seen as one of the worst of the greenhouse gases and coming free with every cow:) or dog or human for that matter.”
Why not use the methane as fuel? Emits 2 H2O and 1 CO2. Is separating the 4 H from the 1C so energy efficient that it’s worthwhile?
PS for global atmospheric CO2, it shouldn’t matter where it’s released, although at what altitude might matter.
Airborne_Again wrote:
We had hydrogen buses running on trial in my hometown for a while so obviously these problems can be solved.
It’s not hard to put heavy thick gas cylinders in a bus, where the weight of the cylinders isn’t much of a factor, and in any case a bus doesn’t have a very high fuel burn to begin with.
It’s a bit different in an airliner that burns 5 tonnes of fuel per hour.
Until we’ve got excess low carbon electricity production, hydrogen will always just be a highly inefficient, dangerous and inconvenient method of burning fossil fuels. Even if we (say) have nuclear, wind and solar capacity 150% of demand, it’s still extremely difficult to store, inconvenient and expensive to store, and not very energy dense per unit volume.
@Maoraigh I think the problem burning methane is the 1 CO2 at least as far as green credentials are concerned. I was really talking about when used in a totally integrated fuel cell. But I don’t claim to be an expert I’ve just been researching and following fuel cell technology for use in off grid buildings.
And of course fuel cells are quiet, not like these noisy fuel burning machines or even wind turbines.
Many researchers claim that the best quality hydrogen, at the moment comes from natural gas with methane being a good source. But you need quite a lot of sh1t to produce enough hydrogen to power a house.The reason many are looking at the fuel cell/hyrogen route is that in PR terms it meets a lot of green credentials plus every now and again there is a leap forward in the prototype technology which everyone gets excited about and is good for keeping those involved in the media eye, for good reasons, before it dies a death again.
Watch out for the next great break throughs such as the storage of hydrogen or methane in solid form. And then there is the theoretical perpetual motion of the Stirling engine which might be able to convert all this free methane into hydrogen, if only they could scale the engine up.
Like mass nuclear fusion this all the stuff of dreamers and idealists but then we need dreamers and idealists. After all where would we be without people like the Wright brothers Santos Dumont, St Exupery and Bleriot, following their dream when everyone said it couldn’t be done.
The avgas tax raise is discussed.
FFA is said to lobby for us but I didn’t hear or see anything about it. Not sure silent lobbying is effective today.
