Science Friday

I wanted to post this yesterday, but ran out of time, so we’ll do this today.

On Wednesday, Raging Dave at the 4 Right Wing Wackos blog posted about GE finding a way to manufacture hydrogen on the cheap, bringing the probability of hydrogen fueled transportation a little closer.

GE says that they believe they can manufacture hydrogen at a price comparable to today’s gasoline (approx $3 per gallon), but if that is the best they can do, we have a problem, and it isn’t in Houston.

When you compress and ignite a liquid to make it combust, whether it be gasoline, diesel, propane, natural gas or hydrogen, you break that liquid down to individual molecules. No engine to this day can contain the entire act of combustion. This is part of the reason your oil gets dirty; because the explosion and it’s residue blows past the piston and the ring seals and gets everywhere, and is mostly sopped up by the other petrolium product inside your engine block.

The nut of the problem is that Hydrogen ‘fuel’ is made up only of 2 hydrogen atoms (H2), a teeny-tiny molecule when compared to say, Isooctane (C8H18) (aka: gasoline), and especially N-Hexadecane (C16H34) (aka: diesel). Models here.

When you try and squish this itty-bitty thing in a combustion chamber, whole lot of it isn’t going to stick around to be blown up so that your piston will go down, it is going to leak past your rings and into your block.

What this all means is that your fuel mileage, depending on the ability of your engine to keep the hydrogen in the combusion chamber, will be anywhere from 3/4 to 2/3 that of a gasoline engine.

Do the math for $3 per gallon fuel and you tell me which one is more efficient.

For those that don’t know, Japan has some of the most stringent emmisions standards in the world. By 50-60K miles, most Japanese owned cars will need to have their motors swapped out because they won’t meet the emission standards (something the eco-socialist cultists would love to impose on us, btw).

I’ve had multiple vehicles (all Toyotas, I’m proud to say) pass the Washington State Emission Standards at 200K miles, so it isn’t that the engines are worn out at 50-60K, they’re just too worn out to meet Japan’s restrictions. There is a industry in Japan for doing quick and easy swap outs and the sheer number of these, because of supply and demand, means that it isn’t quite as expensive as it is here in the US.

Japan being like anywhere else, there is also a cottage industry for faking IDs; but unlike our problem of fake IDs for illegal immigrants, they fake automotive IDs. If you have a hopped up rice rocket in Japan, you don’t want to bring that thing anywhere near the emmissions center, so you buy a scapegoat car, one of the same year, make and model that will wear your rocket’s plates, VIN# and door bar-coded/elecronic ID tag. You drive that to the center, pass the test and then go on with your life. Some of the car clubs even have one car that everyone passes around for test day. Neat little scam some folks have imported to the US *cough-cough*.

So, your engine will slowly leak more and more hydrogen past your pistons & rings, having been built to higher tolerances so as to get the most mileage as possible from the factory, your wear will be at a faster rate than say, a gasoline engine built to lower tolerances, meaning your milage will plummet, probably shortly after 30K. This is especially so if the factory folks have installed eight to ten sets of rings on the pistons instead of the normal three to five to keep all the pushwater in the tube; all those rings grinding on the cylinder walls…ouch. And because it is built to higher tolerances, it will cost more to manufacture, and therefore, more to replace.

One other added expense of hydrogen engines is this: Take a look at the molecular structure of gas and diesel again; that (C) stands for Carbon. When you pop gas or diesel, the residue left behind is 99% burned carbon. Again, that is what gets into your oil and makes it dirty.

So when you squish a fuel made entirely from large amounts of hydrogen and without carbon you get one of the main pluses of a hydrogen powered engine: Water as exhaust, because of the mixing with oxygen molecules.

But add in the leakage problem and you get……hydrogen molecules mixing with oxygen molecules in your engine block, also known as ‘Water in Your Oil’.

Water and oil are bad things to mix. So you have to use the more expensive ‘Synthetic’ oil and change it more frequently. The vast majority of the ‘Synthetic’ oils you are paying $3-$4 per quart for are just blends (as opposed to $1.50-$2 per quart for regular oil), and those will not get you very far in a hydrogen powered car, so you can only use the pure synthetic oil (hence my prior quote marks around the word synthetic) and those cost $6-$8 a quart. Also, you’ll probably want to/have to change your oil every 2K miles in a hydrogen car because, even though most of it will evaporate due to temperature and steam out of your crankcase vent, water in any block is a bad thing. Then add the 10K mile block flushes and you’ve got one very expensive engine to maintain.

Sure, we can make cars that run on hydrogen. Hell, Ford has a Mustang that’ll run 11 second quarter-miles on hydrogen. But we have, by no sane means, perfected it enough for the soccer mom to run it around town or for Bob from Accounting to drive to work.

Sorry to be a party pooper, but Hydrogen is for breathing and swimming in, not for fueling your car.

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9 Responses to Science Friday

  1. Christopher says:

    Part of the reason that Hydrogen is taking so long to do is that it will not be used in internal combustion engines, but in fuelcell cars that will use the recomination of H and O to provide the power which is very energetic, thereby negating all of the problems you have stated. Electrolisis of water can be simply done with a pressurized bank of pure water and KOH (potassium hydroxide, for conductivity reasons) and electrical power from windmills, the only viable way to store the energy from them (hell, we could take all of the old oxygen generators form the subs that they are decommisioning for a start). The only major hurdle left is the containing of Hydrogen and that is what most of the work is going into. As you stated the H2 molicule is very small and loves to permiate everything.

  2. Kirk says:

    Japan also has a nice little cottage industry where someone with a hopped up car who needs to get inspected goes to one of these shops. The shop then take off all of the after-market parts and swap them with the factory parts. You go pass the test and then come back and they swap all of your parts back onto your car. Since they have to pass these tests every couple of years (or every year) it is a nice little industry for those who like to mod their car.

  3. Aaron Neal says:

    I’m not sure, but I think Christopher is right – I haven’t heard any plans of using hydrogen to power cars by burning it, everything I’ve heard has been related to using fuel cells to convert H2 to electricity and run the car with electric motors.

    Could be something in the works that I haven’t heard of, but it’s not likely to be feasible for the reasons you mentioned, Kid.

  4. Analog Kid says:

    I might suggest that you give a glance at these links, Aaron.

    (sorry, I can’t speak fluent HTML)

    As for the swap shops, Kirk, I’d never do that. One wrong wire and you get to buy new brains for your car. Also, when you’ve replaced guts, for say, higher compression, bigger valves, etc, there’s no turning back.

  5. Rivrdog says:

    AK, back in my very brief NRHA drag racing experience in M stock and J stock, the rules for stock classes were that if anyone challenged you on displacement you didn’t have to tear down. Head gaskets and head bolts were expensive, and a tear off of everything down to the block would cost the weekender grudge-racer too much, so those rules were waived. You could overbore .06 anyway.

    Then bracket racing came along, and nothing matters anymore for the average guy who just wants to race other street guys.

    I somehow don’t think those Japanese emissions inspectors can force you to tear down either. My guess is that they can read out most alterations in the data stream from the computer anyway. If they detect any differences from stock in the sensor isolations, such as air mass or throttle positioning, they probably would reject the car anyway.

    I’ll bet that there is beaucoup tech data swapped with an eye towards defeating these comparisons.

    On the subject of electric, that’s where the cars will go. Big improvements in battery tech are just around the corner, and once those improvements are out, you will see the standard of a 150-200 mile range, with freeway speeds, with accessories all running, and rapid recharge of 15-20 minutes.

    I’d probably take your bet that we will see rolling stock with those specs within ten years. Once they become mainstream, with a choice of manufacturers, governments will mandate or incentivize them. Gasoline power will never totally go away, but I could see it as a hobby thing for purists, not daily drivers.

    Hydrogen has too many problems, and requires too much new tech to expect it to sweep the industry. My guess will be a rapid swing to alcohol, which is also a lousy fuel with regard to specific heat figures, then as the battery tech comes out, electric will displace alcohol.

    The beauty of electric is simplicity. Everything is modular, and tweaking is possible without fouling the air. What most people don’t realize is that low-tech electric is available now, and would fill the bill for Mom’s run-around car in most suburban families. With low-tech conversion kits costing $10-$13,000, Mom could be squiring the kids to soccer and ballet, or you could be gliding to the rifle range voltaically as we speak. At typical PNW electric rates, your gasoline-cost equivalent is less than $2.50/gallon, WITH the kit and it’s installation factored in, over the life of the car.

    Kits available NOW will give you 90-100 mile range, and speeds into the high 70’s (65 is tops for freeway economy, though). Recharge times depend on what you want to pay for your charger and what voltage/current setup is available. You won’t get much out of a 15-amp line at 120 volts, but it would do as a top-off while you were at work.

    In a 15 amp line, you can only figure on 12 for charging, and you have to have some for cooling the batteries and line losses, and there’s the conversion penalty, so you expect a light 15 amp line to give you about 500 watt-hours into the batteries. That’s a charge rate of around 40 amp at 12VDC. Since your basic light car kit uses a 96 VDC bank, you are only charging each 105-amp-hour battery at 5 amps, which will repace a 50% discharge in 10 hours. By rule of thumb, that means you can replenish enough juice for about 40 miles driving in your 8-hour workshift (if the boss lets you use a 15-amp circuit).

    The usual charger setup that most opt for at home is a 208/220 line at 30 amps. The car will use about 25 of that, and you can get a total charge in 4-6 hours, a half-charge in 2-3. That charging pattern also fits most second-car use profiles.

    BTW, for another $6-8K, you can give yourself hybrid status by putting together a modern little diesel genset that mounts on a Class 1 trailer, then you are free of chargers and can hit the road. AMC actually built a concept lash-up of this system back in the ’70’s, using a Concord DL that they electrified, and the trailer/generator.

    Electric has possibilities NOW, and many for for the future.

    Those figures work for most people for commuting RIGHT NOW. For a total of $15K, you can buy the car (a light car like a Geo Metro or Corolla/Prizm, the kit and pay for the assembly. You can save a couple thou if you can do the assembly yourself.

  6. Aaron Neal says:

    I stand corrected – partially, at least.

    Middle link kept timing out, but I notice that those are primarily gov’t research. Auto manufacturers, who will be the ones making what we can buy, are investing a LOT of money into hydrogen fuel cells.

    Especially considering all the problem you noted, AK, I see hydrogen being used more for electricity than for IC engines.

  7. Raging Dave says:

    Well, that’s why I leave science to those who have done it before.

    Here’s a question for ya though – I know that GM and Chevy have come out with engines for trucks that run off of propane. I also know that there are quite a few forklifts that use propane for fuel.

    Given that you’re still using a gas instead of a liquid to power the motor, how much of that technology could be used in a hydrogen powered vehicle? Granted, with propane you do not have the issue of water, but escaping gases could still give people issues.

  8. AnalogKid says:

    Heya Aaron, yep, fuels cells are the way to go if I were to use hydrogen, but I’d rather not have to carry the stuff around. While hydrogen moves fast enough that you don’t have to worry about it igniting in a collision, the refuelling is dangerous. Soccer Mom and Bob from Accounting are not qualified to pump large quantities of such an explosive substance.

    If I’m going to have to settle for a car that runs on zap power, I would rather just be able to plug the damn thing into my house/work. I already see my fuel costs as a untility bill, so why not just let me move it directly to my electricity bill?

    Dave, as for propane, it is bound to carbon atoms, and while it is less than half the size of a gas molecule (C3H8 vs C8H18), it has little to no more leakage/pressure problems than gas itself.

    And seeing as how, when you go to fill up your tank with propane (either a tank for you grill or your vehicle’s fuel tank) someone else, trained in the safety aspects, does it for you, there isn’t much of a hazard.

    While I don’t especially mind getting out of my vehicle to pump my own gas, I would completely dislike having the gov’t regulate who gets to do it. That always gets added into the cost of the fuel, again, negating a good deal of any ‘cost savings’ from using something other than petrol.

    If it came down to it, I’d drive a completely electric car, but only if they’d let me charge it at home. I think it is doubly stupid to pay for gas, diesel, propane, pressurized farts, hydrogen, etc, in order to make a rolling electricity powered generator move when I can even more easily just plug and play.

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