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As I said, I don't know how the energy density is with this approach, I'm not enough of a chemist and I'm too busy to do the math right now. If anybody more knowledgeable wants to weigh in, feel free. I've known people to whine about driving around a car with a tankfull of lye, but it's a lot more environmentally benign than driving around with a tankfull of gasoline.

As I said, I don't know how the energy density is with this approach, I'm not enough of a chemist and I'm too busy to do the math right now. If anybody more knowledgeable wants to weigh in, feel free. I've known people to whine about driving around a car with a tankfull of lye, but it's a lot more environmentally benign than driving around with a tankfull of gasoline.

As I said, I don't know how the energy density is with this approach, I'm not enough of a chemist and I'm too busy to do the math right now. If anybody more knowledgeable wants to weigh in, feel free. I've known people to whine about driving around a car with a tankfull of lye, but it's a lot more environmentally benign than driving around with a tankfull of gasoline.

It was still much much easier to get around with the electric assist than without. I had alot of difficulty getting anywhere before and after I had the motor. I'm not a dedicated athlete, I was a college student studying CS at the time. While I did some working out it certainly wasn't enough to keep me in good enough shape to constantly ride up and down the hills in SF.

After awhile you get good at estimating how far you can go without running low on juice. I'd really like to see something with higher energy density like li batteries or fuel cells but it's just not happening. The market is too small for any of the people with that kind of tech to care about. If they were smart they'd develop it and then sell it to China.

Oh and I forgot to mention one technology in the list. A decent system for hydrogen storage. Seriously, this guy has a great idea and it's easy to implement,but nobody seems to be taking him up on it. I'm not sure why.

Not necessarily. We just need massive amount of research for innovative techniques to store and transport hydrogen. Look at this Idea. Basically sodium hydride is pellitized and coated with polythene. Very stable, can be stored for months under water. Once the pellet is crushed, it reacts with water producing hydrogen instantly. No explosions, no pressurized tanks, no transportation problem and yes - no exploding cars. While this might not be a perfect solution, I am mentioning this to illustrate that there might be scores of innovative solutions to the problems of today. We just need the time, effort and money to look for it.

At the filling station, they pump out the broken shells, water and NaOH from your tank, before putting in new water and powerballs. The broken shells are recyclable. The NaOH is reacted with fresh H2 to produce water and NaH.

There needs to be some regulatory rules to make this process as clean as it promises to be. NaOH is nasty stuff, though no more toxic than gasoline. But overall, it's a cool idea.

The primary problem with Hydrogen as a fuel source is not generation (which can be accomplished in large facilities dedicated to the task), but rather in safe, efficient delivery.

One of the most interesting systems I have seen recently is the Powerballs system. It does appear to be a well considered, functional, and (most importantly) *available* system. I don't think this is anything (scientifically) extraordinary, but it is available now.

Hopefully the site will take a slashdotting, they deserve a little publicity, and I'd like to see what others think of the basic idea...I'm not enough of a chemist to understand the efficiency or practicality of their method.

You can find a chemical to store hydrogen. That is how a battery works, or make a gas. These people are trying to make solid sodium and a possible product is PowerBalls Problem: It takes 2000 degrees to make solid sodium, and they use methane as part of the process....not very renewable.

You can store it as liquid H2. Getting H2 to -432 degrees takes power. And it is dangerously cold. BMW has been using this method in their hydrogen cars. A liter of liquid H2 has 39,000 watts of power. Alot of power in a small space.

You can store it as a compressed gas. At standard temp and pressure, a liter of H2 has 3.5 watts of power. Not alot of power here, is there? As you increase pressure, more H2 will work its way out of your tank, and embrittle the metal.

Finally, you can shove H2 inbetween metal. TiFe was patented in 1988, and automakers plan on selling Hydrogen cars in 2010. (Do the math, what technology becomes public domain?) Contaminated TiFe can be reclaimed (it is just like mining it) Ti Sponge (pure TI) goes for $3.80-$4.50 a pound. A research site Texico owns part of Ovonic has a few patents on this technology also.

Now, which way should one go here? LH2? Compressed H2? Chemical? or metal lattice storage?

Without good, "safe" storage, H2 won't be more than a playtoy. Anytime you generate, store or use power, there is danger. It is the preception of Hydrogen danger (hindenberg) that needs to be addressed. Some pinto drivers know how dagerous gasoline is...yet we 'accept' the dangers of Gas. Oh, wait. gasoline, Natural Gas, Propane are chemically stored Hydrogen! Eeek, the horror!

Many people are commenting about the difficulty of storing and transporting hydrogen gas. Here's a company with an interesting idea:

powerball.net

Their idea is to use a low-pressure tank filled with water and "powerballs" -- small plastic covered spheres of sodium hydride.

When the system wants to create more hydrogen gas, it uses a mechanical cutter to cut one of the powerballs in half. The sodium hydride instantly reacts with the water in the tank, producing sodium hydroxide and hydrogen (and a fair amount of heat):

NaH + H2O --> NaOH + H2 gas

When all of the sodium hydride spheres are used up, the result is a tank full of sodium hydroxide. The tank is then returned to their factory, where the sodium hydroxide is converted back into sodium hydride, so there's no waste stream from the process.

The cool thing about this system is that the hydrogen is stored and transported in solid form -- as metal hydride spheres, so you don't have the danger of high-pressure hydrogen to work with. The hydrogen is generated as needed at low pressure.

The site hasn't been updated in a while, so I have no idea if they've successfully brought a product to market, but I thought that this was a really interesting idea, and it would probably work fairly well with these sorts of fuel cells.

Gasoline 4.4x10E7

Diesel 4.3x10E7

Coal 2.9x10E7

FireWood 2.1x10E7

Propane 5.5x10E7

ethanol 2.9x10E7

H-compressed 1.4x10E7

NiCd 1.6x10E4

Pb acid 7.9x10E3

Li + water 3.1x10E7 powerball.net

most of these are from fire.nist.gov

this of course is just the energy, it ignores the storage and conversion costs

For example ethanol gives about the same energy as gasoline, even though it has almost 1/2 as much energy per kg. This is because ethanol can be run at much higher compression therefore more efficent. greenfuels.org

This is what I heard too. Actually when I read it they said something to the effect of "If the government would put more money into research, fuel cell engines for cars could be produced within 3-5 years."

I just had to give a short speech for a speech class last week. I did it on fuel cells. There are a lot of interesting developments going on with that technology. Apparently the only commercially ready fuel cells are phosphoric acid fuel cells (originally developed by NASA about 30 years ago I believe). There are several other types that should be ready within the next 5 years though.

They're also coming up with some interesting ideas for fuel sources. Powerball Technologies had one of the more interesting ideas.

Here's a few more links to check out:

Fuel Cells 2000

Commercializing Fuel Cells

Fuel Cells - Green Power. This is a 36 page PDF file from Los Alamos National Lab

Here's a bunch more.

has anyone heard of powerball