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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?"
If you take a look around at the current state of locomotion, you'll find that steam engines are largely a thing of the past.
What has taken their place? Diesel electric trains.
What's going to be the next big thing in American car engines? Diesel.
Forget steam, it's a toy. Diesel electric will run our cars into the next decades until the oil fields dry up.
Jesus saved me from my past. He can save you as well.
Steam engines usually need to be supplied with water.
The article doesn't state whether it would be necessary to periodically stop and fill up with water, whether it will be a closed system, and if not, will the water supply last as long as the fuel in the tank?
They mention extracting energy from the cooling water as an additional source of energy. But is this related to the water being used in the steam engine?
This article is very thin on specifics, but constantly having to stop and fill up with water sounds like a downside to me...
> no, yes, maybe (tagging beta)
Steam engines need to carry lots of water or provide a large cooler/radiator to condense the exhaust steam back to water for recycling. Bill Lear's plan to put "modern" steam engines into trucks and busses failed because he couldn't solve this problem. The article doesn't address this issue.
If you're only getting a 15% boost in efficiency. Cars are only about 20% efficient and that's if you have a really efficient one. A 15% increase is like going from 15% overall efficient to 17%. This is just a kludge.
There's a much simpler and more effective solution... Go full electric drive hybrid. Decouple the engine from the drive.
Deleted
What is the operating temperature of the engine compared to the environment? What pressure does the steam system operate at? Also, how much does this addition weigh? So I add 10 kW; how much of it is spent on hauling around a steam engine?
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?)
How many modern garages know how to service hybrid batteries? Practically none, other than Toyota, Honda & Ford dealerships.
The nice thing about a steam hybrid is that you don't have any high-voltage electrical cables running through the car -- so after an accident, firemen and police won't need to worry about getting electrocuted when cutting you out of your car.
Conformity is the jailer of freedom and enemy of growth. -JFK
I've been wondering how long it will be before we give up on gasoline/diesel engines and go with fuel cells. Granted, that may be many years away. Anyway, fuel cells generate a lot of excess heat during operation which could be used for generating steam as the BMW does. I think this is a step in the right direction. Despite advances made in recent years, automobile engines are still very inefficient and the focus should be on improving overall efficiency.
Ouch! The truth hurts!
You hydrogen people bother me. Hydrogen is not at all a solution to either the fossil supply or pollution problems. Producing and compressing the hydrogen takes a TREMENDOUS amount of energy that makes the overall scheme much less efficient than burning oil derivatives on-site. The issue isn't getting hydro fuel stations, it's getting the hydrogen without using tons of electricity.
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.
The short-to-mid-term solution to the issues at hand is to produce engines that get much better mileage, like this hybrid, and to get Americans to give up their lust for uber-powerful cars. The long-term solution is effective mass-transportation, alternative energy sources (which hydrogen is not one of), and making dense walkable urban communities close to centers of commerce and industry part of western culture.
I think a good start would be to tax the crap out vehicles based on a pollution coefficient, banning light trucks (SUVs) from the high-speed lanes of highways, legislating a portion of the gas tax to fund mass-transit R&D and construction, leveraging heavy parking fees, raising the gas tax so gas costs $4/gallon, and legislation allowing for small diesel vehicles in the US (currently they are diffucult to produce, they get treated differently than gas vehicles).
"Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails
Although your idea seems nice on the surface, if car life cycles were much longer than 2 years (say, 30-40 years like in Soviet Russia), the manufacturers simply wouldn't have the cash for the steady stream of innovation that gave us our much safer and more economical cars today. And unlike software that we're so cynical about, there has been true and steady innovation and incremental improvement in cars for a long time, at least overseas.
Using petrol is kinda what your stuck with at the moment (or diesel, which is still a fossil fuel).
Most efficient car available is the Honda Insight M5, getting 83.1MPG and having the lowest CO2 emmisions of any car (80g/km, which is about 25% lower than the next contender). Unfortunately they're damned near impossible to get - the best quote I've found is £62,000 and no honda dealer I've talked to has even heard of it...
Next you've got a bunch of diesels (Citroen C2 1.4HDi at 68.9mpg & 108g/km), the Prius is quite a way down the list at 13th (65.7mpg but with lower co2 emissions).
The most efficient petrol engine available (Peugot 107) is only 61.3mpg... I'd like to see the figures for this BMW to see if it can beat that.
(source: http://www.vcacarfueldata.org.uk/)
There had been previous steam-powered cars -- at least three decades before Stanley -- but they seemed to be taking off at right around the same time people like Benz (in Germany) and Daimler (in France) were coming out with gas internal combustion models.
As far as the tradeoffs, Stanley's assessment is described this way by About.com:
"Fundamentalism" isn't about divine morality. It's about human authority.
Heat in the form of engine exhaust, and in the form of friction braking are two major areas of energy loss for a vehicle as well, but only recently has capturing this lost energy been a potentially desirable goal.
This BMW heat capture system seems like a great idea. Ford also has a regenerative braking system called Hydraulic Launch Assist which could capture much of the energy lost in braking as well. Electrics and hybrids already reclaim some of this energy by using it to generate electricity to charge the storage batteries.
It will be interesting to see if the ultra efficient cars of the future use any or all of these technologies.
280+ miles per gallon .
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http://www.canadiandriver.com/articles/gw/vw1litr
Pretty amazing .
A model made with less expensive materials would still exceed 100 mpg .
Ex-MislTech
google "32 trillion offshore needs IRS attention"
Right - increase in efficiency == increase in power == less need for conventional engine power.
For all those who still don't get it, a 15% increase in power means 15% less need for conventional engine. In European terms, that might be something like a 2.5 litre engine now becomes a 2.0 litre engine. (For all you Americans, that's more like a 5 litre engine becomes a 4.5 litre engine.)
Smaller engine == less weight == net equal(ish) minus the emmisions.
I can't imagine how this can be a bad thing, except that as someone mentioned above, the energy cost of making a car easily outweighs something like 10 years of it's use. Thus, a reduction in the need for cars would be far more beneficial than any likely efficiency boosts will ever bring.
I seriously doubt the tribrid idea would fly... electric-drive hybrids run off batteries most of the time with the combustion engine kicking off only during strong-ish accelerations or when the batteries go below a certain point. Most of the time, the gas engine would not run long enough to release enough heat and generate usable amounts of steam. For applications where the gas engine does run long enough for that, this implies sustained heavy load where electric hybrids are not quite worth the trouble.
I saw a video once of people doing 0-100km/h in ~10s with a ~1ton vehicle and 18HP engine... instead of coupling the engine to the wheels, they used it to drive a compressor to pressurize a 4gal 2000psi tank and pneumatic motors. The pneumatic motors were also used for regenerative braking, allowing the car to do repeated non-stop 0-100 runs. You're not going to see this on the streets any time soon though since riding on a 2000psi 4gal tank is very much like riding on a big pipe bomb.
No. All a turbo allows you to do is burn the fuel in the engine more rapidly. You get more power, but at an increase of fuel economy. This solution is making use of the currently wasted byproduct of internal combustion; i.e heat to get more power from the same amount of fuel.
Well, it depends on how you use the turbine. As the exhaust gasses expand through the turbine they cool down. Having a steam engine is just another way of extracting part of the heat that goes out the tailpipe.
So, usually with a turbocharger the turbine is used to compress the intake air, which as you said allows one to produce more power with the same engine. Due to less friction there might be slightly less fuel consumption than a larger equally powerful naturally aspirated engine.
But then, you can instead connect the turbine to the output shaft via a reduction gearing. This is called turbocompounding, and was used in aircraft engines in the late 1940'ies (also, some modern truck engines by Scania use it today). That sure IMHO sounds like a simpler solution than adding a steam engine.
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
From my experiences driving Honda hybrids, I think your explanation is exactly wrong. It appears that the combustion engine is used as the main drive, and the electric engine kicks in under heavy acceleration. Maybe you're talking about other hybrids, though.
Note - I'm basing this entirely on sensation. I've never bothered to research how they work. I just know that it sounds and feels like a normal car when driving, and that under acceleration, I can hear the whine of the electric motor. That, and there's a little assist meter that normally stays at 0.
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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.
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A while back one of the museums that I visited had a steam engine that was about 200 years old (hope I remember that right :-)). What I got out of the demo was:
1) It is fairly simple, construction is simplier than an ICE (internal combustion engine). Someone who knows how to service an ICE can learn to service steam quickly. Of course the question is how easy is it for the mechanic to master the interface between the two engines.
2) Steam engines are very reliable and last a loooong time. If we had steam engines in cars there would be a lot fewer engine problems.
3) Problem with steam engines applied to cars is that warm-up takes quite a while (you need to boil the water...)
4) But supposedly in a pinch it could be designed to use almost any fuel
5) For emissions a steam engine is highly desirable - ICE needs to provide peak energy and burn efficiently at the same time while steam can leisurely build up power and apply it at different time.
For the article, 4 & 5 are not applicable since its using waste heat from an ICE, but it's still food for thought.
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.
Not true.
My 302 CI Mustang has a 9:1 compression ratio. Without a turbo, I would get roughly 22-24 mpg, highway driving. (HP rating to the rear-wheels was approx. 190hp)
A year and a half ago, I took the car and put a 66mm T-4 based turbo on it, making no other changes to the motor. After this modification my gas mileage has increased to approximately 28-30 mpg. And driving around town, there was no change in my mileage, at all. (approx. 480 hp @ 1 bar - more than double previous horsepower rating)
Also, the problems of blowing headgaskets and detonation come from your air/fuel mixture being too lean. You do not necessarily need to decrease your compression ratio, if you compensate with additional fuel. I currently run 1 bar of additional pressure from my turbo. If I desired, I could increase that to 1.2 bar, without changing my compression ratio and still be safe from blown headgaskets by adding more fuel (or more octane).
Yes, many people have problems blowing head gaskets on turbocharged applications, but most of the time the problem lies within their tuning of the vehicle, not on the basis of the setup itself. Basically, unless you are looking to run absurd amounts of additional pressure, a headgasket failure would be caused by tune.
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.
Would this fueling peculiarity be a too small inlet hole for the pump by any chance?
My BMW had it too, I had to hold the pump down at an angle to stop the airlock mechanism shutting it off every 10 seconds! the one bad thing about that car. That, and the fact no one lets you out at junctions because they think you are the stereotypical crap BMW driver!
'By the pricking of my thumbs, something wicked this way comes'
Yeah, yeah...all you "I live in DC and see hybrids" and "I live next door the Sierra Club HQ and see hybrids."
I live in Detroit. And yes, I see a ton of hybrids too.
If that's not a clue that hybrids are here to stay, I don't know what is.
BTW-- a good business plan would seem to go like this:
1. Start/buy a garage.
2. Wait for hybrids to come out of warranty
3. In the meantime, train your mechanics on hybrid technology
4. Be one of the first garages in your area to service hybrids
5. ???
6. Profit!
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Speaking as a man who used to own a 1995 VW Golf, I have to take issue with you on this.
Germans made a car that in theory was reliable and well-built and efficient. In fact it was continually breaking down, costly to fix, had exterior parts falling off every summer when the adhesive softened, and rarely got more than 25 miles to the gallon out of a gutless 2 liter engine. Also, the seats were uncomfortable, and my ignition switch assembly caught fire while I was driving one day.
The 2006 VWs may be better, but my sister-in-law bought a 2004 Jetta, new, and it was totalled when the electric seat heater caught fire.
BMW, on the other hand, is fine. I have fond memories of my Dad's 1984 318i, and wish I still had it.
-- Jeff Paulsen
Steam engines can be made to be up to 90% efficient - but they generally have sucky throttle response, unlike the internal combustion engine which has excellent throttle response, but is less efficient. This makes the solution obvious:
Use an ultra high efficient steam engine in a hybrid configuration, instead of an internal combustion engine. The mechanical engine should only have an electric transmission - ie. steam engine -> generator/batteries -> electric motor -> wheels with relatively small batteries to provide the power at initial startup and instantaneous throttle response needed in a vehicle. There could possibly be a clutch that would provide a direct steam engine -> wheels engagement when in highway cruising, to maximise efficiency but this might could make things too complex.
While the steam plant is cooling down when the engine is "turned off", the steam plant could still be running the generator, to use this otherwise wasted heat to top up the charge on the batteries ready for the next start.
The other advantage is that the vehicle could take a much wider range of fuels without modification, because the fuel is just heating water rather than being burnt in a carefully controlled way like in an internal combustion engine. The same steam plant could therefore just as easily run on deisel, metho, petrol, (unmodified) old chip oil, and mabey even pellet based fuel ( like compressed paper pellets etc.)
The internal combustion engine is dead! long live the steam electric hybrid!
BMW is hardly for the "super rich". I recently bought a used VW Jetta for my wife, and it cost about $9000. A BMW in the same approximate class, with similar features, age, and milage cost $11500 (though it does cost more to insure).
A used vehicle for $11500 hardly puts things in the realm of "super rich".
Even if you compare prices for new vehicles, the perception of BMW as a "rich man's car" is odd. A new 3-series (which, I know from experience, *can* fit 5 rather rotund adults comfortably) can be had for around $33500. A Buick LaCrosse (considered a 'mid-range' vehicle) is $34000. No one trumps up on Slashdot claiming that Buick is only for rich people.
Now, this may put it out of the reach of "working stiffs" like me, but it by no means requires significant wealth to attain.
Besides, new technology is often released to the wealthier folks first so that the R&D gets recouped by early adoption. That initial chunk of sales drives the ability to gear up for the investments that allow economies of scale which bring the tech to a more reasonable price range.
If a company can only profit from environmental tech by selling the first couple batches to the wealthy, so be it: at least the tech gets developed rather than shelved because "it's too expensive for the general public."
We may not imagine how our lives could be more frustrating and complex—but Congress can. – Cullen Hightower