Slashdot Mirror

Here are some real numbers:
* 55% efficiency of fuel->electric in combined cycle plant (powered by crude or gas)
* 85% efficiency of electrolysis
* 50% efficiency of a PEM fuel cell
* ~90% efficiency of an electric controller/motor
* 12% efficiency of an IC engine in an average drive cycle
* 40% efficiency of crude oil->gasoline

So comparing systems normalized on crude oil, and assuming the same transmission and friction losses in the vehicle:
* Crude->gas->ic engine->motion is about 4.8% efficient
* Crude->electricity->electrolysis->fuel cell-motion is 21% efficient. 4.3 times better

To give an idea of how bad current vehicles are a 1995 Ford Taurus throughout the driving cycle only requires on average 6.3 kW (150 MPG) in motive energy, but only achieves ~28 MPG. And that is before addressing issues like reduced weight.

But more importantly hydrogen can be generated by solar, wind, or biological processes. Look at the economics. Wind can be purchased in bulk for ~3 cent/kWh. At 36.6 kWh/gallon gasoline equivalent and 85% electrolyzer efficiency: Hydrogen costs $1.10 per gallon of gas equivalent today using renewables . Right now that is sounding rather good. Not that hydrogen is the end all, but it is a good alternative to oil.

From:
http://www.hydrogenus.com/hydrogen-basics.asp

"The amount of energy produced by hydrogen per unit weight of fuel is about 3 times the amount of energy contained in an equal weight of gasoline, and almost 7 times that of coal. (FSEC)"

Gasoline and ethanol have comparable energy densities. Hydrogen is a MUCH better method to store energy that needs to be used in automobile type applications.

Using the Hindenburg as a comparison isn't fair. Recent studies have shown that the paint used is a near chemical relative to rocket fuel. Hydrogen is no longer blamed for the accident. See this video for more information. (requires realplayer)

The airline industry was lucky in that they worked out all the major glitches well before the advent of mass visual media. Will the space tourism industry manage to avoid killing lots of people while working out all the kinks? Who knows.

I make no claim to know what's true, but here's a little of what I found on the subject.

Addison Bain's working theory (RealPlayer link)

An About.com article


slide

Except it's been decided that the cause was not the hydrogen, but rather the prevailing atmospheric conditions and the unorthodox method of landing at Lakehurst.

Observations of the incident show evidence inconsistent with a hydrogen fire: (1) the Hindenburg did not explode, but burned very rapidly in omnidirectional patterns, (2) the 240-ton airship remained aloft and upright many seconds after the fire began, (3) falling pieces of fabric were aflame and not self-extinguishing, and (4) the very bright color of the flames was characteristic of a forest fire, not a hydrogen fire (hydrogen makes no visible flame). Also, no one smelled garlic, the scent of which had been added to the hydrogen to help detect a leak.

Or were you being sarcastic and I missed it?

Hey everybody! We should completely disregard all research that's been done on the topic of the explosion of the Hindenburg, because because fnj said it was hydrogen without any factual basis, but what the fuck let's believe him anyway.

...that just happened to be made out of the same or similar compounds that the current Space Shuttle solid rockets use as fuel. It wasn't intential. I forgot the properties they were looking for in the paint (stiffness, lightweight?), but it was difficult for them to replace that paint with something else when the designers discovered the "problem".

Some quick links to a description of the real cause of Hindenburg:

ucla.edu
clean-air.org
hydrogenus.com

Enjoy.

Hydrogen and Fuel Cell Letter, June 1998
Shell, April 1999
Time, January 2000
National Hydrogen Association, Spring 2000
Red Herring, July 2000
Fast Company, October 2000
ENN, December 2000
BBC, December 2001
etc.

Darn, I meant to stick this link in my post above. It's got some stuff that might interest you, including some't on fuel cells.

so is bmw. hydrogenus.com only diference is it's not a rotary engine. they have a fleet running now from what i've heard.

The DOE site points to the ttcorp.com site, also mentioned in another 5-modded post. Ttcorp.com has changed its URL for that directory ("nha") to point to hydrogenus.com, the official site of the National Hydrogen Association. The NHA promoted the study and produced an "informative video", Correction History: Hydrogen and the Hindenburg, with an introduction by U.S. Senator Harkin. This so-called "exoneration of hydrogen" was done by a single "retired scientist" and "hydrogen advocate", without peer review.

It seems to at least raise questions of credibility when the primary evidence comes via an industry trade group with an overriding interest in promoting hydrogen, which has gained the favor of a US Senator (lobbying money perhaps?), promoting the research of an unaffiliated researcher's study (could the NHA have been funding him?), which they report without citing any other substantiating studies, scientific journals, or scientists.

The lone researcher's findings were introduced into the Congressional Record, as US Senator Harkin (same guy from the video) presented them to the President of the United States, citing as apparent substantiation that the findings had recently been reported on the cover of Popular Science(!). (For those not familiar with Popular Science, it's a pop newsstand magazine, not a peer reviewed journal). The article itself was also included in the Record, and you'll note that there's a fair amount of discension even within the article.

As others have pointed out, the coating was certainly a factor. As was the weather, and bad luck. But by any conventional accounts, so was the hydrogen. And if you read what the lone scientist writes and listen to what he says carefully, you'll note that he never denies the role of hydrogen in the disaster, he merely promotes the role of the fabric covering. The National Hydrogen Association takes it a step further, with press releases and lobbying efforts about hydrogen being "exonerated," and the coating being "to blame."

I don't know, I'm not expert, but it looks to me like the NHA has done an effective job of rewriting history (or "Correcting History" as their video is called). Type in "hindenburg" and "hydrogen" into Google, and the first hit is to the NHA's site (redirected via ttcorp.com), and most of Google's other first-page hits are unquestioning coverage of the same single researcher's theory. Given the impact it had on this thread, it's disturbing how effective such a simple tactic can be in swaying public opinion.

The DOE site points to the ttcorp.com site, also mentioned in another 5-modded post. Ttcorp.com has changed its URL for that directory ("nha") to point to hydrogenus.com, the official site of the National Hydrogen Association. The NHA promoted the study and produced an "informative video", Correction History: Hydrogen and the Hindenburg, with an introduction by U.S. Senator Harkin. This so-called "exoneration of hydrogen" was done by a single "retired scientist" and "hydrogen advocate", without peer review.

It seems to at least raise questions of credibility when the primary evidence comes via an industry trade group with an overriding interest in promoting hydrogen, which has gained the favor of a US Senator (lobbying money perhaps?), promoting the research of an unaffiliated researcher's study (could the NHA have been funding him?), which they report without citing any other substantiating studies, scientific journals, or scientists.

The lone researcher's findings were introduced into the Congressional Record, as US Senator Harkin (same guy from the video) presented them to the President of the United States, citing as apparent substantiation that the findings had recently been reported on the cover of Popular Science(!). (For those not familiar with Popular Science, it's a pop newsstand magazine, not a peer reviewed journal). The article itself was also included in the Record, and you'll note that there's a fair amount of discension even within the article.

As others have pointed out, the coating was certainly a factor. As was the weather, and bad luck. But by any conventional accounts, so was the hydrogen. And if you read what the lone scientist writes and listen to what he says carefully, you'll note that he never denies the role of hydrogen in the disaster, he merely promotes the role of the fabric covering. The National Hydrogen Association takes it a step further, with press releases and lobbying efforts about hydrogen being "exonerated," and the coating being "to blame."

I don't know, I'm not expert, but it looks to me like the NHA has done an effective job of rewriting history (or "Correcting History" as their video is called). Type in "hindenburg" and "hydrogen" into Google, and the first hit is to the NHA's site (redirected via ttcorp.com), and most of Google's other first-page hits are unquestioning coverage of the same single researcher's theory. Given the impact it had on this thread, it's disturbing how effective such a simple tactic can be in swaying public opinion.

NHA

Why is the slashdot lameness filter so bad???

Do I need an answer, no...