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RX-8 Hydrogen RE a Dual Fuel Car 369

greekgod8591 writes "Japan's Mazda Motor Corp. said on Wednesday it will begin leasing a dual-fuel car that can run on both hydrogen and gasoline in the auto industry's latest effort to reduce oil consumption in vehicles. Mazda said the RX-8 Hydrogen RE, based on its popular RX-8 sports car, gets around these problems by running on gasoline in the absence of a hydrogen fuelling station, and using existing engine parts and production facilities to lower costs."
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RX-8 Hydrogen RE a Dual Fuel Car

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  • by postbigbang ( 761081 ) on Wednesday February 15, 2006 @10:37PM (#14729512)
    Even if someone wanted to pay the $3400+ lease (not including local taxes, licenses, delivery, etc.) there are but a handful of places in North America where you could find a fill. Not that there's even a standard fueling nozzle, nor one proposed to ANSI at this point. You could buy land in Illinois, grow corn, distill your own alchohol and at least have a few places to not only fuel up but some cars that can actually use the fuel for that kind of money.

    And so, this is Mazda's PR machine cooking up hope where it'll be a decade or more before consumers will see something tangible on this side of the Pacific. Must be a dull news day.
    • by EvilCabbage ( 589836 ) on Wednesday February 15, 2006 @10:45PM (#14729563) Homepage
      So is that Mazdas fault, or North Americas?
    • Really. Was that comment worth posting.

      "Oh, it costs $3400 a month. And there are no stations."

      The article says there are only 12 stations in all of Japan. And they are leasing it to a fuel producing company. This is NOT for normal people yet. The end of the article says that they are making plans to lease them to consumers, but that almost certainly means really rich consumers who want a fun little interesting car that is a toy/curiousity to them. They aren't aiming this at Joe Consumer yet. They aren't

      • Honda offered some special lease of a hydrogen powered vehicle to a lucky family in Southern California.http://world.honda.com/news/2005/40506 2 9.html [honda.com]. It still appears that it's going to really rich consumers who want a fun little interesting car.

        If rich families really want to make an impact on the environment and show everyone they care, a better solution would be to trade in their mammoth SUVs and drive a compact car. There's no need for the fancy hybrid or hydrogen vehicle. Current cars using common

    • by rolfwind ( 528248 ) on Wednesday February 15, 2006 @10:51PM (#14729594)
      Um, that's kindof the point of dual-fuel. It's a chicken and the egg problem - would you rather have them wait for the infrastructure? Which will never come because there are no cars on the road that take hydrogen. Because there is no infrastructure?

      Also, corn would not be the only way to get hydrogen. Try electrolysis. Put a few solar panels on the roof, let that electricity seperate water into oxygen and hydrogen and collect in a tank. Inefficient - yes. But feasible. Want something more efficient? Use steam electrolysis (which is more efficient) by putting up a parabolic mirror and heating a core of water to the required temperature (2500 C) and splitting the molecules that way. Some obstacles to overcome - but no reason it needing acres of land when the acreage of a roof should suffice.

      Sometimes the only way forward with this technology is to take a few steps back because it's more realistic to accept it won't be as good (convenient) as gas overnight. Gasoline had years of market acceptance to develop these advantages.
      • Skip the hydrogen and the combustion. Use your solar powered sterling engine or your solar cells to drive a small air compressor which keeps a larger tank topped off in your garage. Your car will run on compressed air.

        http://www.theaircar.com/ [theaircar.com]
        • Compressed air has such low energy density per volume that it makes hydrogen look positively stellar by comparison.

          Compressed air: 17 watt/hours per liter
          Liquid Hydrogen: 2600 watt/hours per liter

          For a 50l fuel tank (standard on my car), you get the equivalent of 12 liters of gasoline (in energy equivalent) from LH2, and the equivalent of a tenth of a liter from compressed air.
      • A far, far better way to do this in most of the U.S.:

        Put the solar cells on the roof, and feed the power back into the grid, lowering your electric bills and your grid power consumption. Then buy a normal car. The grid will burn less coal, balancing out your auto emissions.
        • A far, far better way to do this in most of the U.S.:

          Put the solar cells on the roof, and feed the power back into the grid, lowering your electric bills and your grid power consumption. Then buy a normal car. The grid will burn less coal, balancing out your auto emissions.

          Again, this is how you look at it. If you want to wean the country from oil - the car solution is a better step in that direction. Afterall, that electricity could also be from a Nuclear Power Plant, which is relatively clean. Especial

    • Whats the deal with this whole "lease" thing anyway?
      Here in australia, I only know of people that buy a car outright or people who hire one one from somewhere like Hertz or Avis, not people getting cars on a "lease" basis (ditto with those GM electric cars from a while back)
  • 62 miles? (Score:2, Interesting)

    by jj00 ( 599158 )

    "It can cruise for a maximum 62 miles on hydrogen and 549 km (341 miles) on gasoline..."

    62 miles on hydrogen? I guess there isn't much room in an RX8 for hydrogen with a full tank of gas.
  • by RoboSpork ( 953532 ) on Wednesday February 15, 2006 @10:44PM (#14729554)
    You can really save money driving this thing. With it's 62 mile hydrogen range and its lease price of $3577 per month I figure I could hire a chauffeur with the money I save. Sign me up.
    • by Belseth ( 835595 ) on Wednesday February 15, 2006 @10:58PM (#14729628)
      The point isn't to save money but a proof of concept. Mazda may be in a unique position to exploit rotary engines that can burn both gas and hydrogen. With Bush pushing Hydrogen over other systems Mazda can clean up licensing the technology to other companies. Being able to burn both gas and hydrogen gives them a commanding lead out of the gate in the hydrogen wars.
  • 99% of people who buy a RX-8 buy the car for its speed (and look), not gas consumption rates.
    A weird choice to become dual fuel car.
    • Re:RX-8? (Score:2, Informative)

      by TooMuchToDo ( 882796 )
      Not really. A rotary engine isolates the combustion process better then a standard ICE, which enables it to be Gas/Hydrogen FlexFuel stock. A standard ICE can't do this (currently).
    • Re:RX-8? (Score:3, Funny)

      by EvilCabbage ( 589836 )
      Where's that "missed the point" moderation option?
    • Re:RX-8? (Score:3, Informative)

      by StikyPad ( 445176 )
      It's about alternative energy, not fuel conservation. The RX-8 actually gets pretty crappy mileage, especially if you drive it like a sports car. Also, the RX-8 is the only vehicle Mazda sells (in the US?) with a rotary engine, and the rotary engine is what makes it easier to swap fuels. The biggest advantage is that the rotary engine can't backfire. Backfiring is caused by undetonated fuel being expelled to the exhaust pipe, then ignited on the subsequent cylinder firing. Since the rotary engine intak
  • Thirsty Wankels... (Score:4, Informative)

    by Rdickinson ( 160810 ) on Wednesday February 15, 2006 @10:46PM (#14729564)
    I ran an RX8 (hi-powered, UK) for two years, 30,000 miles. It drinks like a fish.

    Hydrogen , whilst its a nice step forward isnt going to help much overall, and 62miles is ok if you live very close to where you fill up. As for 340miles out of the gas tank, forget it, most mine did was 275, typicaly 200-220.

    Stunning cars though, balance, power and practicality, tho the Hydrogen cycle runs at 50% power and thats with a turbo.

    mazda have had a demo/development duel fuel RX8 for a number of years.
    • As for 340miles out of the gas tank, forget it, most mine did was 275, typicaly 200-220.

      That figures. On Mazda's Australian web site, it says that an RX-8 gets 12.2L/100km and has a 61-litre fuel tank. By those numbers, the furthest it could go would be 500km (310 miles), and you'd have to drive conservatively or spend a lot of your time on the highway to get that. Even then, that's working on the assumption that they didn't have to shrink the petrol tank to add the hydrogen system.

  • by Bullfish ( 858648 ) on Wednesday February 15, 2006 @10:47PM (#14729572)
    I imagine to use hydrogen, that Mazda must have solved the sealing problems in the engine. They first dropped the rotary because of it's poor mileage and leaky rotor seals. I know a number of RX-3s and 4s had horrible problems with their rotor seals. It looks like they corrected that enough for the RX-8 (the 7 had problems too) to be an efficient gasoline engine. Hydrogen seems dicier to me in the regard of sealing. If they haven't corrected the problem enough to do hydrogen over the long term, this will be a flop.
  • by NevarMore ( 248971 ) on Wednesday February 15, 2006 @10:49PM (#14729583) Homepage Journal
    ...on the RX-series as well as the wankel-style rotary engine check out the following:

    http://rx7club.com/ [rx7club.com]
    http://fc3s.org/ [fc3s.org]
    http://www.mazdatrix.com/ [mazdatrix.com]
    http://rx7.org/ [rx7.org]

    and if you live in or near Ohio:

    http://www.ohiorotaries.com/ [ohiorotaries.com]

    These are some of the better sites/forums maintained and populated with rotorheads.

    Its a two way exchange too, if you know anything about multi-fuel or new fuel vehicles we would like to hear from you as well.
  • ... and 341 miles on gasoline. Wow! I can see why everyone is on the edge of their seats waiting for hydrogen cars!

    Can anyone give me a link to some technology on the horizon that shows that hydrogen is really an alternative to gasoline? How is the energy density problem going to be solved for hydrogen?

    In the mean time, hydrocarbons are going to be the primary solution to propelling cars.
    • Since they'll need separate tanks and fill ports for hydrogen and gasoline, the range reflects the size of the two tanks. It sounds like they kept the standard gasoline tank and added a hydrogen tank in some available space.

      This is similar to a propane, natural gas, or butane conversion, all of which have been available for years.

      • It's not only that, hydrogen simply does not have the energy density of gasoline. Barring some miracle breakthrough, gasoline will have the best combination of easy transportation, energy density and price for some time to come. Why waste our time on hydrogen when we know how to deal with methonal or ethonal?
  • Naysayers (Score:5, Informative)

    by Frogbert ( 589961 ) <frogbert@gmail. c o m> on Wednesday February 15, 2006 @11:13PM (#14729685)
    Whenever there is an artical posted about any type of alternative energy there are about 400 trolls complaining that X energy isn't a good enough and that it is a complete waste of time and money to even try.

    Here's the thing, if someone doesn't start the ball rolling it never will start, so its great that Mazda has done this, perhaps it will be a failure, perhaps it will do better then they expected but mainly this is planting seeds.

    The first company to bring out competitive alternative energy cars is going to be in an excellent market position, the only way to do this is to actually start bringing out the cars once they see what works and what doesn't they will be miles ahead of the competition.
    • Re:Naysayers (Score:3, Insightful)

      by thule ( 9041 )
      You can bring out the cars, but until there are compelling reasons for a consumer to shell out their hard earned cash on them, they will not sell. Hydrogen is a great idea, but it's just an idea. Why not take baby steps and use methanol and ethanol? Organisms that produce hydrocarbons sound like a promising idea.

      I suppose it is all about how a person looks at things. If their primary goal it to make a zero emission car, they are totally focused on hydrogen. If the goal is to stop pumping money to unsta
      • Despite the Renesis' inherent ability to burn many fuels (the lack of exhaust->intake overlap is key here, unlike previous 13Bs), it still cannot produce zero emissions, as the engine burns its lubricant by design. Though, the natural progression of logic here may lead to a more important advancement in the automotive industry than hydrogen alone. Think corn oil with more viscosity, suitable for living for thousands of miles in an engine.
    • Whenever there is an artical posted about any type of alternative energy there are about 400 trolls complaining that X energy isn't a good enough and that it is a complete waste of time and money to even try.

      That's because people keep getting their hopes up about hydrogen power, and they shouldn't.

      Hydrogen power pretty much is a waste of time and money because you lose net energy making it - that is, it costs more energy to make than you get from burning it. This is always going to be the case, whether

  • by Doppler00 ( 534739 ) on Wednesday February 15, 2006 @11:39PM (#14729801) Homepage Journal
    There are already a lot of duel fuel propane/LNG/gasoline trucks out there. Most of the places I've seen them though only fill them up with gasoline. Also, the tank for the LNG fills up about a quarter of the truck bed in the back. Same problem, although worse with hydrogen. Since hydrogen naturally doesn't have as much energy densities at similar pressure you have two choices: Make the tank even bigger, or compress the gas to a ridiculusly high pressure. Both choices have their own associated problems.
  • Questions (Score:2, Insightful)

    by neochubbz ( 937091 )
    I wonder when people will realize that hydrogen is merely an energy currency?
    Do they realize that electricity (a.k.a. Fossil Fuels) must still be used to break apart the water?
    Do they further realize that any compressed gas is a pain to transfer anywhere?
    When will people realize that ethanol, until it can be produced in extremely massive quantities (30 gallons per vehicle per week, minimum ), is merely a short-term solution to a long-term problem?
    Why are people nowdays programmed to think just like
    • Re:Questions (Score:5, Insightful)

      by PornMaster ( 749461 ) on Thursday February 16, 2006 @12:04AM (#14729905) Homepage
      The solution, of course, is to use nuclear power to generate more portable fuels. When people realize the inherent relative safety of pebble bed reactors, and the way that fuels such as hydrogen are a storage facility and not an energy source, we'll be far better off.
    • The idea is that coal/nuclear/etc.. power plans are more effecient at producing energy than a small motor in a car. I'd be interested in knowing what the delta is between energy production at the power plant versus in the motor.
      • Re:Questions (Score:2, Interesting)

        The idea is also that even if it were less efficient, it'd still be better to use fuel cells just so long as the energy doesn't come from oil. With fuel cells you can pick and choose the ultimate energy source.

        Green people should really start pushing that angle. There are lots of people who don't care about the environment who do care about saving money (by choosing the cheapest energy source) and about not funding terrorists.
    • Most mass produced hydrogen comes from steam reforming of natural gas (methane) giving you hydrogen and carbon monoxide. Nuclear plants could help make hydrogen with super heated steam. Thing is we still need the methane and end up with allot of CO. Hydrogen is a pain in the ass. Propane isnt that bad. Unfortuantly it is not produced from any natural process that I am aware of. The best fuels are liquid at room temprature. So our best bet is mentanol/ethanol and/or bio diesel. Electric would be my firt pic
    • wonder when people will realize that hydrogen is merely an energy currency?
      Do they realize that electricity (a.k.a. Fossil Fuels) must still be used to break apart the water?
      Do they further realize that any compressed gas is a pain to transfer anywhere?
      When will people realize that ethanol, until it can be produced in extremely massive quantities (30 gallons per vehicle per week, minimum ), is merely a short-term solution to a long-term problem?
      Why are people nowdays programmed to think just like the media
  • Mazda is Ford (Score:3, Informative)

    by minus_273 ( 174041 ) <aaaaa@@@SPAM...yahoo...com> on Wednesday February 15, 2006 @11:48PM (#14729837) Journal
    For those who aren't in the know, Mazda is a division of Ford [ford.com]. Many of the cars use the same components and sometimes they are the same cars with different model names. People looking for a "japanese" car often buy Mazda not knowing they are buying a Ford. Go to the mazda site and compare some of the models to the ford site, the resemblance is uncanny ;)
    • Re:Mazda is Ford (Score:3, Informative)

      by drhamad ( 868567 )
      Someone should have modded that comment up. I would if I had points at the moment.

      Anyway, you're right, Mazda is Ford. To be specific, Ford owns a controlling interest in them of approx 1/3. They use the same engines (Duratec/MZR 23 (I4), Duratec/MZR 30 (V6), though sometimes tuned differently),
      same platforms: (CD3/etc (they use different names) is the Mazda6, Ford Fusion, Mercury Milan, Lincoln Zephyr)
      the Euro Focus (not yet the American), Volvo S40, and Mazda3

      That being said, the RX-8 does not s
    • They may own ~30% of their stock, but the RX-8 parts list shows it's 99% parts made in Japan.
  • by Belseth ( 835595 ) on Thursday February 16, 2006 @12:06AM (#14729912)
    Alcohol engines are a better solution in the short term. Everyone assumes that the hydrogen is going to be produced by electricity but that simply isn't true. Most hydrogen is extracted from fossil fuels, I believe primarily natural gas at the moment. The reason for the big push on hydrogen is Bush is trying to lock us into a oil based hydrogen economy. Most of the investment is in a petroleum/hydrogen based infastructure to make sure we are still oil dependent. Alcohol can run existing cars with minor modifications. It doesn't require the storage systems or distribution systems hydrogen does and can get similar mileage to gasoline, not as much but far better than hydrogen. As for the extra carbon it's carbon active within the environment so it's a wash and doesn't add to the overall carbon. All petroleum products add carbon that has been stored. Alcohol can potentially be extracted from farm waste, plant stalks and such. At worst it comes from corn and the like, even plants like Agave. It'll probably never be a 100% solution but can help as a transitional fuel. An ideal combination would but alcohol hybrides that can be wall recharged and have limited solar cells for helping to top the car when sitting in an outdoor parking space. Given the fact if you were primarily commuting you'd only have to fill it a few times a year the savings would be huge even if alcohol ran 2X what current gas prices are. That's based on the results an engineer got when he simply added more batteries to his hybrid and charged it from the wall at night. The recharging was cheap and he was getting over 200 miles on a tank since he rarely went off batteries. Adding minimal solar cells would drastically reduce gas useage even if it just added 10% to the range. The extra batteries only added a few grand to the cost which would be quickly paid back in savings. Solar cells would add a few grand more but would reduce the alcohol engine to an emergency back. It would only be needed on long hauls and during bad weather.
  • by ikekrull ( 59661 ) on Thursday February 16, 2006 @12:28AM (#14729997) Homepage
    Rotary engines were not used on WW1 era aircraft. These were *radial* engines, with a set of cylinders in a circular arrangement.

    The rotary has some big benefits and some notable acheivements:

    Power-to-weight ratio is excellent. Minimal moving parts, no valve train and short eccentric shafts mean that vibration is very low, and this enables rotaries to rev very smoothly and at relatively high RPM (10,000+ RPM on a normally aspirated rotary in street trim is not difficult). Hot, high velocity exhausts make turbocharged rotaries capable of very high power levels.

    The Mazda rotary has seen enormous success on the racetrack - Mazda is the only japanese manufacturer to win Le Mans, and the RX-7 has been extremely successful - winning more races outright than any other model in major US racing classes.

    A 1.3L rotary engine is easily capable of producing 500bhp with a good turbocharger and fuelling setup, and the most powerful 13Bs used in drag racers produce up to 1000bhp in the extreme (it is true that a 1000bhp 13B will not last long).

    the 2 litre (20B) engine was the torquiest production engine in a japanese car while the JC Cosmo was being made, and the boosted 20B in the worlds fastest rotary does the quarter mile in 6.9 seconds/202 mph with something approaching 1000 bhp.

    The engine that powered the Le-Mans winning 787B in 1991 used a 2.6l 4-rotor normally aspirated engine with ceramic coatings, which produced about 700bhp, exhibited an almost perfectly flat power delivery curve over the entire race, and when disassembled at the end of the 24 hour race, showed practically no wear whatsoever.

    Not only does the rotary produce excellent power for it's weight and displacement, it is also very reliable on a racetrack, or as an airplane engine.

    On the downside:

    Unfortunately heat/cooling cycles are the rotary's worst enemy, as the engine is constructed of a 'sandwich' of different metals, which tend to expand and contract at different rates. This leads to failure of coolant seals (letting water leak into the engine) - analogous to head gasket failure.

    Apex seal breakage is the other major failure mode of the rotary, often due to detonation, or oil starvation.

    Both of the major failure modes necessitate removal and rebuild of the engine block, which is labour-intensive and expensive.

    Fuel efficiency is very difficult to maintain over a wide rev-range because of the shape of the rotary's combustion chamber, which is long and narrow, meaning it is difficult to get a smooth flame front and complete combustion, something piston engines (due to their 'closer to spherical' combustion chambers) have a natural advantage in.

    Ceramic coatings and side-port designs such as used in the Renesis keep heat in the charge and insulate engine parts better, which provides cleaner burns and smoother combustion.

    The Renesis (1.3l 2-rotor RX-8 engine) can burn hydrogen because it's side-ported intakes and exhausts (as opposed to the peripheral exhaust ports in production cars and the peripheral intake + exhaust in race engines) enable a complete separation between the intake, combustion and exhaust chambers, equivalent to zero valve overlap in a piston engine, while retaining the ability to rev high and without majorly impacting on flow.

    This is more or less impossible with a conventional 2 or 4-stroke piston engine - any piston engine running hydrogen either needs a totally different and switchable cam profile which produces anemic performance, or is built to run on dedicated hydrogen fuel and is still a pretty poor performer.

    The Renesis is an outright better hydrogen hybrid engine than anything anybody at any other car manufacturer can come up with, despite their much longer histories and enormous research budgets.

    You can only go 62 miles on a tank of hydrogen in an RX-8, but how far can you go running hydrogen in any other vehicle? Not very.

    Many people trash the rotary out of ignorance, but the truth is that it is the
    • I only read a tiny bit of your post, but your claim that the Renesis can do HCE and piston engines cant or do so badly is totally cracked.

      BMW has been building dual-fuel hydrogen cars for over 20 years. The early ones didn't have variable valve timing, although the new ones do,just like the rest of BMWs engines.

      BMW has been leading the way for decades on HCE research.. the whole picture.. HCE deployment, fueling stations, nozzle/tank technology, etc etc.

      I love the Rotary engine, but don't discount the othe
  • Half the power with 18% of the range of the gas version. No thanks.
  • The big problem with hydrogen-fuelled vehicles is that 1) you need an all-new fuelling infrastructure and 2) the range of hydrogen-fuelled vehicles is still a bit on the short side. Fortunately, today's gasoline (petrol) and diesel engines can get improvements that could tremendously extend the usefulness well into the 21st Century.

    Take for example the diesel engine. We all remember them as loudly clattering, smoky, smelly engines lacking in high-end power. However, thanks to the development of computer-con
  • So has anyone managed to solve this problem? Until it has been, I wont be driving any modified car to run it.

    Hydrogen embrittlement is the process by which various metals, most importantly steel, become brittle and crack following exposure to hydrogen. It is not completely understood. Detection of hydrogen embrittlement in welds and fabricated parts is more difficult than detection of oxidative corrosion (rust).

    The basic corrosion mechanism begins with hydrogen atoms diffusing through the metal as an inters
  • by Brett Johnson ( 649584 ) on Thursday February 16, 2006 @02:12AM (#14730358)
    Because a Wankel Rotary Engine has no valves it makes an excellent hydrogen combustion engine. [The high temperature of hydrogen combustion tends to burn valves in piston engines.] The effect is improved by burning a mixture of hydrogen, air (oxygen), and aerosolized water. The high combustion temps vaporize the water, increasing the expansion pressure. [Note that a hydrogen combustion engine is different than a hydrogen fuel cell engine].

    Wankel rotary engines are underutilized today because of the bad rep they got in the 70's. Their horsepower-to-weight ratio makes them an excellent performance engine for light vehicles (like the Rx7, portable generators, and airplanes). They tend to be weak on the torque side, however. [Performance piston engines often can built with 1-1 horsepower to torque ratios.]

    The lightweight, simple, valve-less structure of rotary engines make them good candidates for alternative fuels. However, current rotary engine designs require injections of small amounts of oil to lubricate the apex seals. This oil is combusted with the fuel and expelled. [Typical oil consumption on a 13B engine is about 1/2 quart per 1500 miles.] Unfortunately, even when burning hydrogen, this tiny amount of burned hydrocarbons disqualifies the engine as a "zero emissions" vehicle - no research grants - no subsidies - no ZEV tax credits.

    http://www.millville.org/Workshops_f/kess_mech/too ls/1tools/hydrogen.html [millville.org]

Make it myself? But I'm a physical organic chemist!