Talk:Hydrogen internal combustion engine vehicle

Possible addition to article
hey guys where should i put this info for it to be relevant? "Mileage of a hydrogen internal combustion engine can also be enhanced from the effects of a combined energy recovery and water electrolysis system which would improve mileage by enabling the conversion of wasted energy into usable hydrogen fuel. Regenerative braking would be one way to make such electrolysis systems save fuel without violating the laws of thermodynamics because it allows these systems to be powered by recovered energy which would otherwise be wasted. A significant amount of energy could be recovered from regenerative braking which could be used to power an on board water electrolysis system in order to increase available fuel. "  — Preceding unsigned comment added by Nullyoa (talk • contribs) 10:14, 14 November 2019 (UTC)

Untitled

 * The german article is about an engine and this article is about a vehicle, its on my todo list to create an article about the engine. Mion (talk) 11:31, 10 March 2009 (UTC)

Kind of low improvement
The power output of a direct injected hydrogen engine vehicle is 20% more than for a gasoline engine vehicle and 42% more than a hydrogen engine vehicle using a carburetor[2][3].

20% ? seems very little, TCEV is 30-40% efficient, gasoline ICE is only 20%, increase is thus 50% —Preceding unsigned comment added by 81.243.178.120 (talk) 05:49, 14 August 2009 (UTC)

& as well from Kenya Patrick Murage Karuku have improved the cooking system with hydrogen. —Preceding unsigned comment added by 41.139.141.138 (talk) 16:34, 29 December 2010 (UTC)

Low Emissions
I noticed the "low Emissions" section says, "when a hydrogen fuelled engine is tuned for greatest emissions it produces emissions equal to a gas fuelled car from 1976" (I paraphrase). What about when tuned for minimum emissions? Doesn't this wording and lack of minimum emissions info seem slanted against hydrogen cars? — Preceding unsigned comment added by WertMooMoo (talk • contribs) 08:07, 5 June 2014 (UTC)
 * well, if you read it possitive, the test was done in 1976 and compared to 1976 emissions from regular gas engines, and it states that you could get the extra power output from hydrogen and maxed in emissions it wouldn't be higher than that from gas engines. Also you would go for the minimum emissions from an environmental point of view, economics would demand that you try to max power output of the engine, the maxed emissions is a worst case scenario for modelling, in practice you have less emissions. Mion (talk) 15:50, 5 June 2014 (UTC)

Reference 11 on fuel cell vehicles
Reference 11 directs to a site (not a PDF) of the US government about, among others, fuel cell vehicles and not about combustion engine vehicles. Besides that I cannot find any numbers on output power.

Besides the above mentioned, I think it would be worth mentioning the usage compared to the extra output power. — Preceding unsigned comment added by Al126 at wiki (talk • contribs) 12:47, 6 April 2015 (UTC)

The H2 + O2 + N2 → H2O + NOx equation
This is a bit silly. Sorry, though, I just don't have the time.

The equation does not take into account EGR/PCV. With a ideal cat and ecu tune the products will be H2O + N2 with zero NOx emissions

With exhaust gas re-circulation/PCV + ECU + ideal cat converter, the full equation is H2 + O2 + N2 + H2O + N2O + NOx == H2O + N2

External links modified
Hello fellow Wikipedians,

I have just modified one external link on Hydrogen internal combustion engine vehicle. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Added archive https://web.archive.org/web/20110905043908/http://www1.eere.energy.gov/hydrogenandfuelcells/tech_validation/pdfs/fcm03r0.pdf to http://www1.eere.energy.gov/hydrogenandfuelcells/tech_validation/pdfs/fcm03r0.pdf

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 10:12, 9 November 2017 (UTC)

Mercedes Benz Hydrogen ICE, 1990
In 1990, the Arizona State University Engineering and Science Library hosted an exhibit by the American Hydrogen Association. In addition to a hydrogen-powered Cessna airplane engine, was a Mercedes Benz automobile with hydrogen gas tanks fitted into the trunk. This vehicle is glaringly absent from the History section. It was probably the nitrogen emissions that put a damper on the project, much to the ire of the many auto mechanics trained in ICE conversions. Today it would be simpler, no need to drill holes into the cylinders since fuel-injection. Computers would need reprogramming to inject the correct gas mixture. Both hydrogen and oxygen gas tanks would produce zero emissions.

Engineering challenge: gasoline burns at a much lower temperature than hydrogen/oxygen. New materials, cooling system redesign, .... — Preceding unsigned comment added by Hpfeil (talk • contribs) 17:01, 4 October 2019 (UTC)

Nitrogen Oxides produces by engine
A statement that nitrogen oxides were produced in excess of the permitted quantity referenced the German-language Wikipedia as a source (red flag!!) for the HICEV page in that wikipedia. It also mischaracterised the commentary on nitrogen oxides produced by hydrogen combustion. The reality is that the production of NOx is dependent on the fuel-air ratio and the overall setup of the engine (as that impacts residence time of nitrogen), this is similar to how a typical hydrocarbon internal combustion engine can produce NOx. 5.151.23.56 (talk) 20:04, 5 May 2022 (UTC)

I would also point out that if Oxygen is used instead of air, there is zero NOx produced. The production of green hydrogen via renewables produces both Hydrogen & Oxygen as two separate products. There is no reason why two fuel sources cannot be utilised.144.139.103.173 (talk) 09:31, 20 June 2022 (UTC)

Carnot limit
The article claims that hydrogen internal combustion engines are not subject to the Carnot limit. This is incorrect. Gasoline ICEs are definitely subject to the limit, and all that is being changed is the fuel. I propose that sentence be deleted, or at least marked "disputed". Hfoltz (talk) 21:23, 11 September 2022 (UTC)


 * This is puzzling. I find countless references that gasoline (and hence hydrogen) ICEs are subject to the Otto Cycle that cannot be more efficient than the Carnot Cycle. But the reference cited by an unknown editor on 2022.08.31, ] claims "open cycle" with up to 100% efficiency. Could this be a spoof or fake? Theosch (talk) 18:42, 24 December 2022 (UTC)
 * I think I made this comment. My stance is that open cycle engines are not subjected to the Carnot limit. It's stated in a presentation from Oak Ridge National lab on improving engine efficiency and it's stated as a very common misconception. 2607:FB91:FBC:4A2A:7C7C:F2FF:FE5B:CDD8 (talk) 01:44, 14 July 2023 (UTC)
 * Sorry now I see you linked to the presentation. My non math way of thinking about it is more that with a closed cycle and fixed mass of working fluid you have to get back to where you started to do another power stroke and allow some heat to flow that can't do you any useful work because you're having to do it in the opposite direction. I'm not sure how you could mathematically prove this but I would think it would have to do with the working fluid mass being pumped out of your control volume/boundary you are considering for your thermodynamic system. With a closed cycle there is no mass flow out of your CV. 2607:FB91:FBC:4A2A:7C7C:F2FF:FE5B:CDD8 (talk) 01:57, 14 July 2023 (UTC)

HICEV engine still produced CO2
By the nature of the ICE process it still produces some CO2, as explained in this video: https://www.youtube.com/watch?v=3IPR50-soNA&t=152 — Preceding unsigned comment added by Americanu197 (talk • contribs) 15:50, 25 July 2023 (UTC)

Efficiency
In the article this is written: "This reference is unique in suggesting that the maximum efficiency of internal combustion engines is not limited by the Carnot cycle, that it is an open cycle engine with a theoretical efficiency limit of 100%." It is not clear to me, which reference this should be pointing to, but anyhow, this is against high approved physical basics. Helmigo (talk) 10:39, 5 November 2023 (UTC)
 * I checked the refs in that paragraph and the revision history and found that it is the ref in the preceding sentence. I rewrote it to clarify the nature of the ref and explain the basis of the claim more clearly based on it. I do not make any claim as to the validity of this analysis. It's possible we should just remove it altogether as exceptional claims require exceptional sources and this disputed claim does not have a strong WP:RS basis. DMacks (talk) 15:31, 5 November 2023 (UTC)
 * I checked this: The reference is about a theoretical possible internal combustion engine, that works with a chemical expansion, while hydrogen internal combustion engines work with thermal expansion (as all other practical existing internal combustion engines do). The information in the article, that the theoretical maximum efficiency of hydrogen internal combustion engines is higher than that of fuel cells is definitely a contra factual information. Helmigo (talk) 14:51, 4 January 2024 (UTC)