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Steam Hybrid Car from BMW

RMX writes "BMW is unveiling its turbosteamer hybrid engine, which uses the excess heat in the exhaust system and reclaims 80% of it by powering a steam engine that assists the gas engine. Overall, this gives a 15% more efficient engine; and significant additional performance (power and torque) with practically no downside. "This project resolves the apparent contradiction between consumption and emission reductions on one hand, and performance and agility on the other," commented Professor Burkhard Göschel. Are steam engines the future of environmental-friendly hybrid vehicles?"

25 of 663 comments (clear)

  1. Downsite? by Short+Circuit · · Score: 5, Insightful

    ...with practically no downside.

    Additional moving parts, and servicability? How many modern garages know how to service a steam engine?

    1. Re:Downsite? by ivan256 · · Score: 5, Funny

      ...the huge plume of steam coming out the 'smokestack' on the top of your BMW....

      Just kidding, of course. It's probably a closed system, but the headline of this story certainly produces some amusing mental images.

    2. Re:Downsite? by Sique · · Score: 4, Informative

      German online news site Spiegel Online has more details on this:
      Heat plant in the car. It uses a high temperature (up to 550 Celsius) circuit using water and a low temperature one using ethanol (alcohol) (operating at 150 Celsius). Both are closed systems.

      --
      .sig: Sique *sigh*
    3. Re:Downsite? by JesseL · · Score: 4, Informative

      Don't forget that most turbocharged engines will give up some fuel efficiency as compared to a naturally aspirated engine of the same displacement even when operating under light loads. This is because in order to handle (without blowing head gaskets or detonation) the increased charge density provided by forced induction, they must use a lower static compression ratio. Lower compression ratio generally equals less efficient combustion.

      This is why Saab developed this.

      --
      "Prefiero morir de pie que vivir siempre arrodillado!"
    4. Re:Downsite? by TheMadcapZ · · Score: 5, Interesting

      Actually the supercharger is considered less efficient at higher RPMs because of the parasitic drag on the motor that consumes up to 40% of the horsepower to just drive the blower. Now this may not be an issue when the blower increases hp by 60%, so your net gain is still greater than without the blower, but the turbo does not rob the engine of horsepower like the blower does.

      It is interesting to note that Volkswagen has come up with a new engine that is just 1.4 liters, yet it utilizes a supercharger and a turbocharger. The supercharger supplies boost until the turbo spools up, then an electro magnetic clutch disengages the supercharger. It peaks at 170 hp with a fuel consumption of 47.9 mpg.

      Twin Charger

    5. Re:Downsite? by 2b · · Score: 5, Funny

      "but i'd rather have a steam engined harley davidson"

      Unfortunately there's no way to make a steam engine loud enough to satisfy the average Harley owner. Too bad, since they're already accustomed to steam-engine performance.

    6. Re:Downsite? by SomeoneGotMyNick · · Score: 4, Funny

      Perhaps there will be a steam-electric-fuel hybrid (tribrid?) at some point...

      We'll go straight to Quadbrids. Steam/Electric/Fuel/Gravity (for when the other three, through a loose screw somewhere, interact themselves into a tangled mess). You can use the fourth drive method to coax it home. Wait, maybe it's a Pentabrid. Add the Biomechanical drive to push it home.

  2. Real world value ... by LazyBoyWrangler · · Score: 5, Insightful

    Although the idea seems nice on the surface, how much more energy goes into refining the metal for the additional engine? How much weight is added? How much cost is added? Although many of these schemes seem beneficial, when evaluated over the lifespan of the product it may be a net zero or net loss from the existing technology. If people would stop buying new cars every two years, we would be better off than everyone buying the newest, latest greatest enviro-trendmobile constantly.

    1. Re:Real world value ... by hey! · · Score: 4, Interesting

      Although the idea seems nice on the surface, how much more energy goes into refining the metal for the additional engine?

      And how much effort goes into raising obscure questions nobody is likely to have the answer for?

      But in this case, intution with a little math can be a reasonable guide. Most people have no idea of the fabulous amount of energy the expend by driving around. A gallon of gasoline contains about 131 megajoules of energy, or roughly 124000 BTUs.

      To melt steel, according to Google, is 377 kWh/mt. Since a kWh is about 3.6Mjoules or 3413 BTU. So, a single gallon of gasoline has enough energy, in a modern electric furnace, to melt over thirty six metric tons of steel in a modern electric furnace.

      Now granted, we have to include the energy of the entire process, including mining transportation, and so forth. Supposing the cost of melting the steel is 1% of the total energy costs in creating the extra components. In that case a gallon of gasoline is sufficient to produce not 36000 kg of steel component, but 360 kg. Let's generously guestimate that is approximately the weight of a single unit.

      Suppose with the added weight the net gain in efficiency is not 15%, but say 1.5%. Thus a car getting 25mpg now gets 25.25 mpg. Suppose the user drives the car 15,000 miles per year. In that time on the pre-unit version he uses 600 gallons. On the post unit vehicle, he uses 594 gallons, for a savings of six gallons.

      Under these highly pessimistic assumptions, the energy for creating the unit is paid back in two months.

      However, I doubt the unit weighs nearly 800 lbs; nor that a 15% increase in powerplant efficiency with modest weight addition would result in only 1.5% increase in vehicle efficiency. Note that the article is claiming that the net efficiency of the car increases by 15%. It's not inconceivable that the manufacturing energy could be recouped in a single fill up.

      Americans for some reason have a weird bias against efficiency; I always hear these kinds of objections when an idea to make something more energy efficient comes up. It's almost like we're afraid of it.

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  3. BMW an innovator in alternative fuels by digitaldc · · Score: 5, Informative

    BMW has the ability to make Hydrogen-powered production cars, it is a shame that they have not caught on yet.
    Current fuels will eventually go the way of the steam engine, or wait, maybe not the steam.

    Interesting site: http://www.bmwworld.com/hydrogen/

    --
    He who knows best knows how little he knows. - Thomas Jefferson
  4. BMW Philosophy. by Volanin · · Score: 5, Funny

    Quote from the company's press release about BMW's philosophy towards efficiency:

    "A reduction in consumption amounting to a few percentage points over the entire model range exerts higher overall effects on the general population than high percentage points for a niche model."

    Now the company just has to make BMWs available to the "general population"!

    --
    If I clone myself, can I call it a thread?
    If a girl winks to us, can I call it a race condition?
  5. Steam engine options by thewiz · · Score: 5, Funny

    I wonder if they will offer a steam whistle as an option to replace the car's horn.
    It certainly would get the attention of the person in front of you preening themselves in their rearview mirror!

    --
    If "disco" means "I learn" in Latin, does "discothèque" mean "I learn technology"?
  6. Repairs... by pedestrian+crossing · · Score: 5, Insightful

    How many modern garages know how to service a steam engine?

    I would think that BMW dealerships would be able to service BMW autos, no? Yes, I understand the rush to FP, but do you think maybe they'll have this covered by the time they go into production?

    I am glad to see some innovation to the standard IC engine.

    But I guess it's just easier to sit in your armchair and criticize real engineering...

    --
    A house divided against itself cannot stand.
    1. Re:Repairs... by Short+Circuit · · Score: 5, Insightful

      I would think that BMW dealerships would be able to service BMW autos, no?

      Sure, the dealership will know how to service it, but that wasn't what I was referring to by "garages". I was referring to those independent garages where you can often get cheaper, better service. I don't take my 1991 Plymouth Voyager to a Chrysler dealership; They're booked solid and will want to replace half the car. I take it to a small guy on the outskirts of the city who comes up with cheaper solutions .

      Oh, and fooey on FP. I really don't give a damn; it just happens more often because I'm a subscriber.

    2. Re:Repairs... by MindStalker · · Score: 4, Insightful

      I know a few people who work in garages, and here is how it goes. Lets take the new hybrids for example. The first hybrid models came out about 5 years ago. At that time the garages did not worry about learning them as they all had warrenties and nobody is going to take a new under warrenty car into a garage. About 2 years ago this local garage realized that eventually they would need to be able to service these new cars, so they sent a few guys to some classes to learn. I believe the garage is now certified to work on these cars, right as the cars are starting to come out of warrenty. Many smaller garages are waiting a bit longer though untill there is enough demand for service as such cars would only account for a very small percentage of their buisness (not many hybrids were sold in the first couple years, so it will still be a while before you see many hybrids out of warrenty)

  7. New every 2 isn't such a problem... by Myself · · Score: 4, Insightful
    The used cars don't get crushed as soon as the first owner is done with them, they go onto the used market and hopefully allow less enviro-trendy people, who just want a new car, to replace the old gas-guzzler they'd been driving. The new green-mobile will be sipping less gas throughout its entire lifespan, no matter who's at the wheel.

    The trouble is when people buy new cars that are NOT environmentally friendly, those cars also continue to guzzle for as long as they're on the road. If the average vehicle coming off the assembly line were more efficient, then we'd be pushing out the older crap with newer, better stuff. But the average fuel economy of ALL manufactured vehicles has actually DROPPED since the 1990s:
    ... availability of four-wheel drive. The increasing market share of these vehicles, combined with their lower average fuel economy, has contributed to a lowering in overall average fuel economy since the mid-1980s.
    from Automobile and Light Truck Fuel Economy
  8. I'm holding out... by Ric0chet · · Score: 4, Funny

    ...for a Mr. Fusion Home Energy Reactor add-on for my Delor..er...Nissan.

    --


    How you see the world is how the world sees you.
  9. Next Thing They'll Invent... by FrankDrebin · · Score: 5, Funny

    ... a network of metal tracks to operate them on.

    --
    Anybody want a peanut?
  10. Re:Where's the Condenser? by blakestah · · Score: 4, Informative

    The pictures accompanying the article suggest the system interfaces with the relatively large radiator already in the front of the car. It is not going to produce nearly as much steam as an engine that would power the entire car, and this steam engine doesn't need a heat source either.

  11. Could be combined with conventional hybrid... by Goonie · · Score: 4, Interesting
    One thing people don't seem to be grasping here is that this technology is essentially orthogonal to conventional combustion-electric hybrids. There's no reason (aside from not owning the tech, of course) why Toyota couldn't add this to the Prius IV, and make it more powerful and even more fuel efficient than it is today. Or, alternatively, it could be added to those European diesels some of you are so enamoured with. The limiting factor, of course, would be size, weight and cost - could you really have room for both the steam system and the paraphenalia of a hybrid car, and could you afford to add both?

    I'm a bit skeptical that really make this practical, but it's an impressive idea; a combined cycle automobile-sized piston engine.

    --

    Any sufficiently advanced technology is indistinguishable from a rigged demo
    --Andy Finkel (J. Klass?)
  12. Re:You Hydrogen People by flyinwhitey · · Score: 4, Insightful

    "The only thing hydrogen is good for is to reduce emissions from the vehicles themselves, but you only end up pushing the pollution to power generating stations, which we'll need a lot more of if the 'hydrogen economy' takes off."

    And which are signifcantly more efficient than masses of cars spewing less refined emissions, especially nuclear plants.

    Essentially your post says "punish auto owners, and reward mass transit users" while completely ignoring the fact that mass transit is impractical in many places and always will be.

    --
    How pathetic are you that you follow me from topic to topic and waste all your mod points at once modding me down?
  13. Re:Choo choo by Guppy06 · · Score: 4, Informative

    " I think you are confusing fuel and engine form. Diesel is just a fuel, it doesn't dictate the engine type."

    Oh yes it does! Just try putting diesel fuel into your Otto Cycle automobile!

    The Diesel Cycle is inherently different from the Otto Cycle in that there are no sparkplugs. As opposed to an external ignition source, diesel engines use nothing but the compression in the cylinder to ignite the air-fuel mixture. Overgenerallizing a little, diesel engines operate entirely on what you would call "knock."

    I could go on about temperature vs. entropy comparisons between the Diesel and Otto cycles, but your eyes would glaze over.

    For the same compression ratio, the Otto Cycle is more efficient than the Diesel Cycle. However, when engineering comes into play, you can have much, much greater compression ratios with a Diesel engine than an Otto engine. The source of ignition in a Diesel Engine is the pressure in the cylinder, and the pressure is uniform throughout the chamber, ensuring uniform combustion and uniform expansion of the cylinder. You can get away with building cylinders, say, 1 m in diameter. With the Otto Cycle, because you need an ignition source (sparkplugs), combustion in the chamber will be non-uniform and there will be more energy lost because of it, so F-1 and GPX cars use many, many cylinders that are very long but very slender. Only a fool would use an Otto Cycle engine to power a locomotive, let alone a ship.

    "So... there's no reason you couldn't make a highly efficient diesel external combustion (probably steam) engine."

    No. Diesel means internal combustion. If you want external combustion, you build a steam turbine (far fewer moving parts), and they don't care what you burn. There's no reason to burn something as expensive as refined diesel fuel. Modern steamships burn whatever it is the refineries can't sell to anybody else.

    You could try a gas turbine, but, again, diesel fuel isn't designed for that; it will ignite when you don't want it to, and not ignite when you need it to. Go with kerosene.

    "So... there's no reason you couldn't make a highly efficient diesel external combustion (probably steam) engine."

    Not a mechanical engineer, are we?

    "If the water runs out,"

    Then you take it back to the dealer. The water isn't supposed to come out, you put your superheated steam through the preheater, getting it back down to saturation before you put it back into the boiler again. You should no less run out of water than you would run out of motor oil or transmission fluid (with similar Very Bad Things happening to your engine if you do).

  14. Re:You Hydrogen People by uradu · · Score: 5, Informative

    > The only thing hydrogen is good for is to reduce emissions from the
    > vehicles themselves, but you only end up pushing the pollution to
    > power generating stations, which we'll need a lot more of if the
    > 'hydrogen economy' takes off.

    Except that you're missing a critical piece here: since hydrogen extraction facilities are very large and stationary (something most cars are not), they can use fuels that would simply not be an option for the cars themselves, such as wind, solar, wave or nuclear power. And even if you do keep producing hydrogen by burning fossil fuels, because of the size and relatively low number of production facilities you have the economic luxury of investing in technologies that burn fossil fuels more efficiently and transform waste into more benign forms than would be feasible in the cars themselves.

  15. Re:I've been waiting for this by EmagGeek · · Score: 4, Informative

    You can't take heat from the catalytic converter because that heat is required to catalyze the gasses. That's why emissions suck for the first 5 or so minutes that you run your car - the catalyst is cold and not doing its job. That's also why urban areas use MTBE and other oxygenates in fuel in the winter time - so that the mal effects of the cold catalyst are mitigted.

  16. No, this is a Combined Cycle by IvyKing · · Score: 4, Interesting
    What BMW is doing is more long the lines of the combined cycle power plants - where the exhaust heat from gas turbines are used to make steam for steam turbines. The Stanley Steamer is more akin to a conventional steam plant.

    Curtis-Wright did something similar with the turbo-compound engines, where exhaust turbines were coupled to the crankshaft - got about 20% more power for a given fuel consumption - and allowed the DC-7C and L-1649's to go from New York to London/Paris nonstop.