NASA Tests Hydrogen-Fueled BMW

Rio sends us word that NASA has completed an 8-week test of a fleet of BMW luxury sedans powered by liquid hydrogen at Kennedy Space Center. The new BMW Hydrogen 7 sedan uses the same fuel that powers the space shuttle and reduces CO2 emissions by 90 percent, according to a news release. Its engine can burn gasoline or liquid hydrogen and can switch seamlessly between the two. From the article: "One hundred BMW Hydrogen 7s have been built, and 25 are used in test programs in the US. The cars have already covered more than 1.3 million miles in test programs around the globe."

Comments

Solution to the H2 problem

[E 99]

Using earth-based H2 power doesn't make a lot of sense, since there's no real energy-efficient way to make it. However, what if we (seriously) built enormous space tankers capable of making the trip to Jupiter and scraping H2 out of the surface of its atmosphere and compressing it into liquid to bring back ginormous amounts to earth? It's a long round-trip, but if there was a fleet making continuous deliveries, at some point this would scale to to the point where it was an incredibly cheap form of energy. The only real downside, is we're making the Earth no longer a closed system -- what will be the long-term effect of the added H2? Will the world's algae keep up with the loss of oxygen as we burn all of that?

Re:How efficient are they?

[Chris Burke]

And unless I didn't sleep through physics, the 2nd law of thermodynamics tells me that this better be some really, really clean way of generating H2.

It's a bit like the electric motor. Sure, it's the most efficient kind of engine, converting more than 95% of the energy put into it into movement, but first of all someone has to generate that electricity to run it. And that means... 2nd thermodynamic law, it would have been probably more efficient and less waste heat producing to use the primary energy source to generate movement instead of converting it to power and then use an electric motor.

The 2nd Law says nothing about how efficient a process is, only that it will not be 100%.

A power plant is more efficient than an automobile ICE. Even if both are burning hydrocarbons dug up from the ground, the power plant will be more efficient and produce less pollution largely due to the scale. It's much easier to add expensive and heavy scrubbers to a coal plant smoke stack than to the exhaust system of a car. It's easier to make an efficient engine when the weight of the engine is not a concern.

So your 95% efficient electric engine times a 40% efficient coal plant is better than your 35% efficient ICE with much better emissions controls to boot. And that's using coal, which I'm certainly not a fan of.

Which leads me to the big advantage of electricity-based transportation (whether it's electric batteries or electrically produced hydrogen from water) which is that once you have decoupled power generation from transportation, when you bring online new environmentally friendly power plants you can use this new source seamlessly with no disruption to the transportation infrastructure. Already we're producing far more "green" electricity in this country than we are using "clean" transportation, and this has happened without you even having to be aware when you flick the light switch. We should be so lucky as to be able to do the same with transportation.

Basically what I'm saying is that electric/hydrogen power has efficiency and environmental advantages now, but also has the potential for vast improvements in the future and that's even if you keep the exact same car!

Solar power? Would be cheap, but the production of those solar cells is creating a horrible amount of waste and they're far from efficient. Wind power? Even worse. And pretty much everything else isn't CO2 neutral.

If you're going to look at the environmental cost of solar power, then you should include the environmental cost of acquiring oil. Adding every cost associated with ICE-based cars or coal power plants certainly do not make them look better compared to solar power.

And what's wrong with wind power again? It's not bird deaths, those were never any more than city office buildings produce, and new designs that discourage nesting on the turbines has put it in the noise.

Re:How efficient are they?

[Chabil Ha']

Is it efficiency that we're after or dependence on, say, oil? As long as oil (or some other foreign nonrenewable resource) wasn't heavily involved in the process of creating the H2, isn't that a plus? As much as the sky is falling over what we're doing to the environment, shouldn't we overcome the issue of renewable energy before we focus on what it does to the environment?