Hydrogen Fuel Cell Cars

a hydrogen-fuel-cell car for $600/month in southern California only. The fuel cell in that car probably costs $100,000 to $200,000, so the point is green branding, and to beta test their car.
GM is also leasing an H-car, but is indicating they are backing off H-cars in favor of plug-in battery cars, like the Chevy Volt, which should be out in 2 or 3 years. These probably make more sense. The thing is not to put all our eggs in one basket. Many solutions are necessary.

Hydrogen is an energy carrier
Coal, oil, gas, uranium, sunshine, volcanic heat, and tides, are all energy sources, but hydrogen is not. All of the earth's hydrogen has been burned already and all that is left is hydrogen oxide, H₂O, water. Saying water is a fuel, as some oil companies have, makes as much sense as saying burned up coal, carbon (di)oxide, CO₂ is a fuel.

So what good is hydrogen? It's an energy carrier, exactly like electricity. Like electricity, hydrogen is made by using a real energy source: fossil fuel or some alternative energy source. At best, hydrogen will make some alternative energy source more useful, but so far there has been no problem finding good uses for alternative energy. So the main hydrogen economy idea comes down to this:

Someday, when we have more wind or nuclear power than we need to make electricity, we can use it to make hydrogen to run cars and heat our home.

That's the idea as it was originally conceived in about 1913, and as proposed in Scientific American in 1973. Originally wind turbines were to be the energy source, but since about 1970, nuclear energy has been the favorite.

Hydrogen fuel cells, wind power, and cars
Some of these were used in space flights back in the 1980??s, which increased their sex appeal enormously. But, what are they. They are essentially batteries that are recharged by adding a chemical fuel, hydrogen, natural gas, or even powdered coal.

Here are two ways to drive on wind power.
1. Wind => electricity => Battery in car => motor turns wheels
2. Wind => electricity => hydrogen => Fuel Cell in car => motor turns wheels

With a normal battery the electricity comes over the wires to your house, you plug in your car, it goes into the battery, and then the next day, it comes back out and runs your car. With a fuel cell, the electricity is first used to make hydrogen then that is put in your cars hydrogen-powered-battery (call a fuel cell) and the next day electricity comes out of the fuel cell, just like it comes out of a battery.

The advantages of fuel cells might be that they hydrogen tank and fuel cell combination needed to drive 300 miles could be smaller cheaper and lighter than a battery pack needed to drive 300 miles. Right now, it's the other way around. Second, the conversion of electricity to hydrogen and then back to electricity might waste less energy than charging a battery and using it. But right now, it's the other way around.

So, a present, batteries are ahead of fuel cells. Fuel cells are getting better, but so are batteries. The important point is that neither will come close to perfection, and so it is unlikely that fuel cells, which are way behind a present, will ever be very much better, and they probably won't be any better at all for a very long time.

Fossil to hydrogen for cars
Currently, almost all hydrogen is made from fossil fuels, and when you use 1 unit of fossil energy you only make about 0.9 units of hydrogen energy at best. Nothing is perfect.

Making hydrogen from wind would generally be wasteful. Every unit of wind energy used to make hydrogen instead of electricity means that fossil fuel will be used to replace the electricity that wind did not generate. So, is it better to use the fossil fuel to replace the wind-generated electricity (so wind can make H) or to generate hydrogen directly? It is more efficient to use wind to make electricity and natural gas to make hydrogen.

This means the best we can do is make hydrogen from fossil fuel. (There is some chance nuclear power will eventually have a bit of an edge.)

In the future, hydrogen could improve the efficiency of electricity generation--a little. In this way hydrogen use could conserve energy. Read about this on the "hydrogen economy page."

Hindenburg 1937

zPoint: Hydrogen (H) is not a source of energy. It's like electricity; first you make it with fossil fuel, then it carries energy to your house/car, where you use the fossil-fuel energy. Hydrogen is an energy carrier.

Now, almost all H is made from natural gas (NG). The more hydrogen we use, the more NG (a fossil fuel) we must import. So why not just put the natural gas in the car? Actually, there are more natural-gas cars than H cars. Here's the theory of how H might be better:

100 Natural Gas ==> 85 Hydrogen ==> 43 Electricity ==> 39 Driving power*

vs.

100 Natural Gas ==> 25 Driving power

The numbers measure energy units. In theory, with hydrogen, 100 energy units of natural gas could give 39 units of driving power, and that's more than you get burning the natural gas in today's cars. But even in theory, hydrogen cars use lots of fossil fuel.

In practice, energy is wasted compressing the hydrogen and delivering it to hydrogen stations. So the driving energy drops to about 34 for hydrogen. If natural gas or gasoline is used in a hybrid car, it can give us about 35 units of driving power.

The bottom line is that hydrogen cars will be about as good hybrid cars in theory, someday. But right now they are not, and they are about 10 times as expensive. The best estimates say hydrogen cars just might be a help starting in about 2050.

* These value are rough, but qualitatively correct.

zPoint #2: Hydrogen gets in the way of practical solutions. There is no chance hydrogen will save more oil and CO2 than hybrid cars in the next twenty years, and it’s a toss up even in 2050. Rifkin, a huge advocate of hydrogen, tells us DOE cut off its efficient-car program when it switched its attention to hydrogen.

Officially the FreedomCAR is a research program. But, the hydrogen-fuel-cell car (H-car) is its centerpiece. This will save little if any fossil fuel and it won't be practical for forty or fifty years. FreedomCAR is mostly Hydrogen Hype.

FreedomCAR wastes money that should go into hybrid cars, fuel efficiency for standard cars, and even nuclear research. It's time to stop the hydrogen hoax and get down to business.

Judging Hydrogen (H-) Cars
An H-car is similar to a Toyota Prius. You put chemical fuel in their tanks, they convert that to electricity (some of which they store in batteries). An electric motor turns the wheels.
The Prius has one advantage: the gas engine that generates its electricity can help turn the wheels.
The H-car has one advantage: the fuel cell that generates its electricity is more efficent than a gas engine.

President Bush on Hydrogen Cars, April 22, 2006

Bush: I strongly believe hydrogen is the fuel of the future.

zFacts: Actually, it's an energy carrier like electricity, not a fuel like oil. This means we have to make it with a real fuel as we must make electricity, by burning gas, oil, coal or uranium.

Bush: Hydrogen is used in a fuel cell that can power a car that uses no gasoline,

zFacts: No gasoline in the car, but 99% of all hydrogen is produced with fossil fuel.

Bush: produces no pollution or greenhouse gas emissions.

zFacts: But these are produced when the hydrogen is made, and it takes about 15% more fossil energy to make the hydrogen than ends up in the hydrogen.

Bush: Hydrogen vehicles can be twice as efficient as gasoline vehicles.

zFacts: The best hydrogen vehicle can be twice as efficient as bad gasoline vehicles. But according to the best authorities, hydrogen cars will not improve overall energy efficiency until at least 2050, and maybe not then.

Bush: Hydrogen can be produced from domestic energy sources,

zFacts: It is produced domestically from natural gas, which means we have to import more natural gas.

Bush: which means it has the potential -- a vast potential -- to dramatically cut our dependence on foreign oil.

zFacts: Yes, by increasing our dependence on foreign gas.

So what's up with the push for hydrogen?
The only way the hydrogen economy makes sense is to produce hydrogen from nuclear power. And this only makes sense once we have more nuclear power than we can reasonably use to produce electricity. The nuclear industry is the real force behind hydrogen.

http://zfacts.com/p/285.html | 01/18/12 07:21 GMT
Modified: Thu, 10 Apr 2008 03:25:28 GMT