Filed under: Hydrogen, BMW, Green Daily
Video: Jay Leno speaking about the goodness of the BMW Hydrogen 7
So here's a video (thanks to J. Villarreal) that shows Jay Leno driving his BMW Hydrogen 7. Leno is evidently delighted with the car and states the benefits of driving it, such as the lack of difference between driving on hydrogen or driving on gasoline and how the car (which doesn't have a fuel cell but an ICE) is exactly the same as any other car and how nice is not feeling anxious about being stranded when running out of fuel, since you can still use gasoline. He also shows himself confident on how fast the hydrogen fuelling stations can be deployed, comparing telephone and computers but (and before you comment on this), he doesn't mention how the H2 was obtained.
[Source: GreenEnergy via Webcastr]
Reader Comments (Page 1 of 1)
regguy 3:09PM (11/30/2007)
"...but (and before you comment on this), he doesn't mention how the H2 was obtained."
Yes,...and before you wear anything cotton did you know who was forced to pick it before the emancipation?
There will be enormous progress on delivering "green" H2 irrespective of the nay sayers, and the "black" H2 (no pun intended) from steam reformed natural gas will disappear.
The all-eggs-in-one-basket (Egglectrics) won't deter the multiple solution approach, but will they volunteer for the power lines in their backyard???
Reply
cdub 4:49PM (11/30/2007)
What this video doesn't mention is the absolutely HORRIBLE Hydrogen and Gasoline mileage this car gets:
http://www.spiegel.de/international/spiegel/0,1518,448648,00.html
"The company says the car will consume an average of 13.9 liters (3.7 gallons) per 100 kilometers (roughly 17 miles per gallon) using regular gasoline and a whopping 50 liters to drive the same distance when fuelled by hydrogen.
In other words, BMW has created an energy-guzzling engine that only seems to be environmentally friendly -- a farcical ecomobile whose only true merit is that of illustrating the cardinal dilemma of a possible hydrogen-based economy."
Reply
GoodCheer 5:23PM (11/30/2007)
Does anyone know how the tank is kept cold enough to keep the hydrogen liquid (-423F / -253C)?
If you park the car for a couple days, will it boil off and blow out the tank? Or is the super-chiller powered by the hydrogen even when the car is not in use, so it can keep the tank cold right up until there is nothing left in the tank to cool?
Reply
regguy 5:29PM (11/30/2007)
cdub, don't be lazy, do your own research.
The energy equivalence of gasoline to H2 is about
1 gal. gasoline = 1 kg. H2
The tank holds 8 kg. and can go 125 miles with about 7 kg. The system switches to gasoline before the tank is emptied. This is about 17-18 mpg energy equivalent.
For a full size car to get that mileage around town is respectable.
The point of the H7 is not to re-invent the Prius. Look up the mileage for diesel 1 Series and MINIs if you want that comparison.
Reply
BlackbirdHighway 5:40PM (11/30/2007)
It's not really useful to say it takes 50 liters of hydrogen to go 100 km. A kilo of hydrogen is about equivalent to a gallon of gasoline, but to convert liters to kilos, you need to know the density. BMW stores the hydrogen under pressure and in liquid form, so it constantly boils off. Park your car too long, and there will be no more hydrogen left.
So not only can that be expensive having your fuel leak out, but there is also some research going on to determine if that leaked hydrogen might be even worse for the ozone than the banned CFCs.
But hey, most of the time you'll be running on just gasoline power anyway, so it probably doesn't matter.
Reply
Chris M 6:33PM (11/30/2007)
GoodCheer: The Hydrogen 7 uses the best insulation available, a double walled vacuum insulated dewar type tank. Even so, enough heat leaks through to boil away the entire 30 gallons of H2 in just 2 weeks.
regguy: Due to the low density of liquid H2, a Kg takes up approx. 4 gallons in volume, so 1 gallon of gasoline is equivalent to approx. 4 gallons of liquid H2. cdub was right, the fuel milage is really poor, especially considering the modest performance. I still suspect someone at BMW is trying to make H2 look even worse than it is!
Reply
regguy 6:35PM (11/30/2007)
To Blackbirdhighway:
"...but to convert liters to kilos, you need to know the density."
It is liquid H2 stored at close to absolute zero so it doesn't get much denser.
"BMW stores the hydrogen under pressure and in liquid form, so it constantly boils off. Park your car too long, and there will be no more hydrogen left."
Driven every other day there is no boil off because the H2 is being used.
"So not only can that be expensive having your fuel leak out, but there is also some research going on to determine if that leaked hydrogen might be even worse for the ozone than the banned CFCs."
The H2 that boils off is run through a catalyst and is emitted as that stuff that falls on your face when it rains.
Maybe we should try to stop the oceans from pumping water vapor up into the stratosphere.
Reply