Mercedes Classe B Hydrogen (Spy)

[Touareg 2.5]

It sounds almost too good to be true, but cars which run on hydrogen fuel cells emit only water vapour into the atmosphere and in contrast to oil, hydrogen is not a fossil fuel with only limited reserves. In fact it is the most common element on the planet. Car manufacturers are seemingly uneasy about propagating this form of motive power. Research has been going on for decades and numerous breakthroughs have been announced. So far though, only a handful of prototypes and some limited series production vehicles have appeared. A fuel cell car is basically an electric vehicle since the fuel cell stack is used to combine hydrogen with atmospheric oxygen. The chemical energy from the reaction is then converted into electric power which drives the vehicle.

Matthias Brock from Daimler in Stuttgart said he believes that the fuel cell is very promising when it comes to zero-emission driving in local areas. Mercedes has around 100 test vehicles underway – the world's largest fleet of fuel cell vehicles. The company is currently working on a B-class with fuel cell power which could be produced in limited numbers from 2010. "We estimate that between 2012 and 2015 the car could be ready for series production," Brock said. We snapped a test-fleet of hydrogen-powered B-classes in the U.S. desert.

While other manufacturers, such as Volkswagen in Wolfsburg, are more reserved about committing themselves to future fuel cell models, the general opinion is that the fuel cell offers the only truly zero-emission drive system around. GM, for examples, states that “at the moment we cannot see an alternative."

Whether cars need to be completely emission-free is another issue. Andreas Ostermeier from the German federal environment ministry in Dessau said that the notion of zero-emissions is an irrelevance. Petrol and diesel engines no longer pose a threat to air quality. Petrol engines which comply with the Euro-5 standard laid down by the European Union use the latest technology to reduce toxins to levels far below those of even a decade ago. The same will apply to diesels when Euro 6 becomes legally binding from 2014. "Nowadays fuel consumption and a reduction in carbon dioxide emissions are at the top of the agenda," Ostermeier said.

Hydrogen is complex to produce which puts the fuel at a further disadvantage as conventional fuels continue to get cleaner. It is also an expensive fuel source as one example shows. Hydrogen can be gained by using steam to reform natural gas. "The trouble is that so much energy is used to drive the process that it is cheaper to pump the methane gas used straight into a gas-powered car," Ostermeier said. The German expert does not share the car industry's optimism that one day it will be possible to produce sufficient hydrogen using renewable energy derived from wind, biodegradable refuse and hydro generation. Ostermeier said it could take until 2030 before enough electricity from renewable sources becomes available. From an overall energy point of view it was probably better to rely until then on conventionally-powered cars, especially since the coming years are set to see the arrival of electric cars with far more efficient batteries and a wider range than those currently on the market.

In regions such as South America, bio-fuels could be the most viable alternative whereas in highly-populated urban regions in Western Europe the pure electric car offers the most potential for the future.

WCF

Suppongo questa soluzione venga usata nella prossima B... a meno che in quel di Stoccarda non decidano di accelerare i tempi.

[Matteo B.]

sta faccenda dell'idrogeno si muove veloce ultimamente...sarà FORSE perchè se si hanno a listino modelli ad emissioni zero si può "aumentare il punteggio" per rientrare nei futuri limiti di gamma di Co2 ?

:lol::lol::lol:Happy

FORSE, eh?

[jeby]

Ma IMHO sono sperimentazioni che vedranno i risultati, se li vedranno, tra mooooolti anni. L'idrogeno ha grosse potenzialità, ma anche problematiche enormi, di sicuro non è la soluzione a breve-medio termine.

[Matteo B.]

Ma IMHO sono sperimentazioni che vedranno i risultati, se li vedranno, tra mooooolti anni. L'idrogeno ha grosse potenzialità, ma anche problematiche enormi, di sicuro non è la soluzione a breve-medio termine.

jeby, più di una casa ha parlato chiaramente di piani per avere a listino un modello ad H2 tra il 2012 e il 2015....comprabile da me e te....non sperimentale...

in piccola serie le auto ad h2 già girano nel traffico normale in giro per il mondo...NON prototipi guidati solo da collaudatori

[jeby]

Le case possono dire quello che vogliono, ma se manca la rete, non si trova un modo efficiente per produrlo, trasportarlo e stoccarlo, sarà solo l'ennesima presa per i fondelli. Anzi, potrebbe non avere vantaggi rispetto alla benza né in termini di CO2, né in termini di costi e soprattutto avrebbe altri svantaggi in più: tendenzialmente gli stessi svantaggi dell'uso del metano a bordo di una vettura ma elevati all'ennesima potenza. Senza contare che il metano non devi produrlo (anzi, è quello che si usa per fare l'idrogeno, tra gli altri sistemi) e comunque si liquefà a pressioni abbastanza ragionevoli per il trasporto in vettura (oddio... 200 bar...) a temperatura ambiente. Per l'idrogeno invece devi spendere molta più energia per liquefarlo, solitamente si deve pure abbassare (e mantenere bassa) la temperatura.

In piccola serie ci sta perché non devi organizzare una rete nazionale (europea, mondiale) di distribuzione, ne produci e trasporti quantitativi limitati e, appunto, fai sperimentazione.

Non dico che non sia utile investire in queste ricerche, ma secondo me le tempistiche sono molto ottimistiche.

Modificato 24 Settembre 2008 da jeby