Tuckerfan, to say 40% of power is lost in the transmission is preposterous. The number is much lower. A steam powered car might lower it a bit but will not eliminate it. Now add the greater weight of the steam engine etc and you have a net loss.
The loss isn’t solely in the transmission, remember a car engine produces a lot of heat which is thrown away, the alternator, A/C, and powersteering units also sap power from the engine. Regretfully, I can’t find an on-line source that gives a complete break-down of the losses, but IIRC only 35% of a gallon of gas actually makes it to the wheels. The rest is lost because of the reasons I mentioned above. Drag racers often remove the alternator from their engines because of the horsepower losses.
Steam engines are also very light weight in comparison to ICEs. If my damn PC hadn’t crashed a couple of weeks ago, I’d be able to find the various sites that talk about all of this.
Anyway, here’s some sites that talk about recent work on steam cars, including a British attempt to set a new landspeed record!
http://www.geocities.com/ResearchTriangle/Lab/1135/pritch.htm
http://www.firedragon.com/~kap/Barrett/
http://www.exford.co.uk/Steam/home.htm
http://www.geocities.com/MotorCity/Shop/3589/index.html
Here’s a [cite that mentions a bit (no stats that I can find) on some of the things that drain power from an engine:
This [url=“http://www.geocities.com/MotorCity/Shop/3589/efficiency.html”]page](http://popularmechanics.com/automotive/concept_cars/2001/1/GM_hybrid_gets_80_mpg/index3.phtml) has a comparison between a steam powered car and a gasoline one.
I’d post more, but it’s late and the boards are about to go down.
I am not an expert but that seems to be implausible. Without transmissions how does the car change gear, such as increasing torque at the cost of speed?
I would imagine that’s the same with a steam engine.
Steam turbines are not the same as steam engines for one thing. Don’t new fire power plants use gas turbines nowadays anyways?
Besides, scale can make a big difference in what you can do with efficiency.
So if steam is so efficient, why did diesel locomotives replace steam locomotives? Startup time isn’t important for railroads, and many steam locomotives ran on oil. (Sorry for the hijack but I think an answer to this might shed some light to the OP.)
Tuckerfan, you are doing a lot of generic affirmations but nothing concrete.
>> The loss isn’t solely in the transmission, remember a car engine produces a lot of heat which is thrown away,
As I said before, show me a steam engine which is more efficient.
>> the alternator, A/C, and powersteering units also sap power from the engine.
So? Steam powered cars do not need alternator, A/C or powersteering? This is totally irrelevant. Show me a steam engine which can compare favorably in efficiency, weight/power ratio, eleasticity, convenience, etc with an internal combustion engine.
>> Regretfully, I can’t find an on-line source that gives a complete break-down of the losses, but IIRC only 35% of a gallon of gas actually makes it to the wheels.
Show me a steam engine powered vehicle which can do better that a vehicle powered by an internal combustion engine.
>>The rest is lost because of the reasons I mentioned above. Drag racers often remove the alternator from their engines because of the horsepower losses.
Conclusion: remove the alternator from your car and you get better mileage whether it is powered by steam, ICE or your legs. You’ll also get a ticket for having no lights. And you can’t hear the radio. ::sigh::
>> Steam engines are also very light weight in comparison to ICEs.
Again, I’d like to see some supporting evidence. I am not taking your word for it.
>> If my damn PC hadn’t crashed a couple of weeks ago, I’d be able to find the various sites that talk about all of this.
I’ll believe it all when I see the evidence.
>> Anyway, here’s some sites that talk about recent work on steam cars
>> cite that mentions a bit (no stats that I can find) on some of the things that drain power from an engine:
Totally, absolutely, 100% irrelevant to the discussion at hand. They drain power from any engine, regardless of the type.
Your other links add nothing in support of your assertion. The last one is about a GM powered by diesel. How that is relevant to this thread I have no clue.my damn PC hadn’t crashed a couple of weeks ago, I’d be able to find the various sites that talk about all of this.
You’re not exactly a patient man, are you, sailor? I’m working on getting the info as time permits. When my harddrive crashed I lost my bookmarks, but not the steam related webpages which I saved. I’m pulling them up and attempting to backtrack to the correct url (not always easy). I’ll be more than happy to e-mail you those pages and the scanned documents I have if you absolutely, positively must have the information now.
No, it’s not. A steam powered car with an 80 lb engine doesn’t need as large an alternator as a gasoline powered car. For one thing, a steam powered car wouldn’t have spark plugs. If you throwout the computer controls, there’s even less of a power drain. A lower power drain means that more of the engine’s power is going directly to the wheels.
And [here’s a link to a forum of steam car collectors and enthusiasts.
[url=“prsteam.inventdata.com.au/index2.html”]Here’s](http://www.steamautomobile.com/FORUM/list.php3?f=1) a link to the website of an Australian inventor who has built a steam powered car that he’s trying to raise the funding to be able to mass produce. I will admit, it’s probably the ugliest looking thing on four wheels.
Here’s a link to an article discussing Skoda’s recent research into building a steam powered car.
>> A steam powered car with an 80 lb engine doesn’t need as large an alternator as a gasoline powered car.
You just made that up.
>> For one thing, a steam powered car wouldn’t have spark plugs.
The ignition uses susch a smal amount of energy that it will not be much relevant unless the steam engine is in fact more efficient.
>> If you throwout the computer controls, there’s even less of a power drain.
a) the amount of energy used by the onboard computer is miniscule
b) in any case it is irrelevant because computer controls for the combustion would still be needed. You can build an ICE without computer controls but it so happens it is more efficient with a computer.
You are bringing up a lot of peripheral and irrelevant stuff.
Show me a steam engine that fullfils:
a) comparable in power, size and weight with an ICE in a car
b) as efficient as an ICE
c) as responsive as an ICE (go from 5% output to 100% output in a fraction of a second)
you can take all the time you want but in the meanwhile you will forgive me if I continue to believe it does not exist and that is the correct answer to the OP. If I believed it exists then i would have to jump on the conspiracy bandwagon to find reasons as to why it was not widespread. For now I believe my explanation makes more sense.
The Stirling Cycle engine (where a gas is used as the working fluid (instead of steam) is an interesting device. I remember that FORD had a joint venture with PHILIPS years ago, to develop a SCE capable of use in a passenger car. I believe that the Stirling engine has great potential, but the technical hurdles are immense-I think the FORD/PHILIPS design used helium as the working gas, which has an annoying tendency to leak through seals. Is anybody still trying to develop this?
Finally (now I’ll shut up), I remeber a serious proposal to bury giant electrical cables under the roadways, powered with AC-cars would have induction coils , which would pick up the power, and the electricity would power an onboard electric motor. Neat!-however, you would probably have to use most of the world’s copper to wire up downtown LA!
IC engines can uses both fuels, with efficiencies not very different from gasoline-powered engines.
As others have said, the main issue is whether one could acheive a power-to-weight ratio within the range for IC engines.
How 'bout a hybrid with a very small gas turbine to charge the batteries instead?
Pardon me for continuing the hijack, but this is an interesting question; there several reasons but these may not be relevant to steam-powered automobiles. Most sources I’ve read state that the main considerations were a)diesel-electric locomotives required far less maintenance personnel and infrastructure than rod-driven steam locomotives b) diesel-electric locomotives apply maximum tractive effort over a wider speed range than rod-driven steam locomotives.
In the '40’s and '50’s, the railroads experimented with both rod- and electric-driven steam turbine locomotives, but the efficiencies gained were not considered sufficient to justify building such locomotives in large numbers.
During the energy-crisis years of the late '70’s and early '80’s American Coal Enterprises promoted a modern coal-fired, rod-driven steam locomotive design, called ACE 3000, that used condensing technology. ACE’s literature claimed lower operating costs than contemporary diesels, but this assumed crude oil prices in the $40-45/barrel range. When fuel prices fell back to lower levels, the project was abandoned.
Interstingly, railroads are also looking into hybrid diesel/battery- electric locomotives for low-speed operations. One company has built a switcher using this technology and claims much improved efficiency and lower emissions compared to ‘pure’ diesel-electrics. Sorry, don’t have a URL to point to at the moment.
Quote Tuckerfan
"You’re not exactly a patient man, are you, sailor? "
You sure are right there.
He also ignores the fact that in whatever he is compareing,in this case steam engines vs ICE, the information he is asking for is not available because the steam engine has not been commercially produced for decades like the ICE.
Technology can do wonders when its turned loose.
Interesting note the land speed record was won with a 350 hp steam driven engine.
Cecils toyota probably has that much HP
He’s correct on that one. Early steamers didn’t have transmissions. A steam engine produces acceptable torque over a much broader rpm range than an internal combustion engine, and can, in fact, operate at very low rpm. You can simply design the vehicle with a drive train geared to produce the desired top speed for the vehicle at top engine speed, and allow the engine to be throttled back far enough for all lower speeds.
You still obviously still have to have a differential, which will incur some loss, and have to make some provision for reverse. I don’t believe early steamers had a way of disengaging the drive train for a “nuetral gear” - if you wanted to be idle, the engine didn’t turn. You sat there with the boiler ready, and when you wanted to go again, you just turned on the steam and spun the engine up. The steamers, like locomotives, had arrangements for reversing the action of the camshaft so the car could be driven backwards.
Electrics don’t need transmissions either. Like a steam engine, an electric motor can simply be operated over a wide rpm range. The GM EV-1 did not have a gearbox, for instance (the specs say “single speed transmission”), and 1900-1930 electrics were marketed heavily on “simplicity of operation”, including not having to mess with gear shifts. The need to shift gears is something we have grown used to with IC engines which only operate acceptably in narrow rpm ranges.
Back to the main bout.
Thanks for that information! I found a detailed description. This bit is interesting:
So it seems to me that if you use the same fuel, steam propultion using reciprocating steam engines and conventional technology is less efficient than internal combustion.
yabob: Just out of curiosity, since the modern steam engine we are talking about is usually a turbine can’t you use a transfer case connected directly to the turbine itself using a simple, but effieient variable buffer plate (compress for greater speed, relax for lower speed/revolutions) to control speed? It seems to me that a transfer case is already a fluid turbine anyhow. It also seems that using this method the system efficiency would increase at higher speeds. Am I off on my understanding of the transfer case here?
justwannano
>> "You’re not exactly a patient man, are you, sailor? "
>> You sure are right there.
I told him he can have all the time he wants. I will believe it when I see the evidence. “Believe me now and I’ll show you the evidence later (maybe)” doesn’t cut it with me and I do not think it is reasonable to expect otherwise. I would appreciate it if you stick to the matter under discussion and leave personal attacks to one side.
The fact is that I do not see any evidence that a steam engine comparable to an ICE is possible today with the technology we have.
>> Technology can do wonders when its turned loose
That is a lot of general handwaving. I want to see some concrete evidence.
My explanations is that steam engines have not been developed for cars because ICEs perform better. What is your explanation?
Yes, but not primarily for efficiency reasons - for lower capital cost and easier siting reasons. (but a much higher O&M cost - it’s a short-sighted solution)
Now, come on. That is not helpful.
You have a couple of very good points here, but the fact is that steam power production research (especially in the power industry) has not remained static - it just has not been applied to automotive use. Also, with all due respect, no one can really tell if there would be any significant advances in making practical, everyday steam automotive use available if it had had more research and been produced for many decades. Or if there would be in the future.
Quote sailor
“My explanations is that steam engines have not been developed for cars because ICEs perform better. What is your explanation?”
Quote from http://www.exford.co.uk/Steam
“Fred’s record was beaten by more powerful petrol driven vehicles, but his Steam Land Speed Record (SLSR) lived on for almost 80 years. It was only bettered in 1985 when Bob Barber, another American, raised the record to 145.607 MPH in a modern steam turbine car.”
OK like I said “the information he is asking for is not available because the steam engine has not been commercially produced for decades like the ICE.”
It costs lots of money to retool for something as drastic as a completely different type engine. Detriot will continue to produce what is currently has if it is not profitable to tool for something else.Simple economics so don’t ask for a site.
Your 35% figure is decent, maybe a little high, depending on the application. However, your points about alternator, A/C, power steering, etc. are not valid. A steam car would need all of these things.
The ignition system on the car takes so little power it’s laughable, relative to the headlights, brake lights, interior fans, windshield wipers, and so forth. And the computer not only draws almost no power, but it is almost certain that an “advanced technology” steam car would need the exact same level of computing power - if not more - to control its combustion heat processes and steam side as well.
If I look at the Geocities link you posted, I see the following text:
Now let’s break this down.
This person claims, without any note of his references, sources, or personal professional qualifications, that the steam power plant car will be equivalent in energy consumption to that of a gasoline car on the highway, but better than a gasoline car in stop and go driving. For the following reasons:
- no “idling” at stops
- no “riching” of fuel/air mixture during acceleration
- no fuel consumption during deceleration or “coasting”
Two of the three (and sometimes three of the three) “advantages” can be covered by hybrid cars.
Aside from the fact that his efficiency numbers, and his sweeping statements on the efficiency numbers is just bullshit.
In spite of any impressions I might give, I’m no expert either. “Transfer case”, as I’m familiar with the term, refers to the device in 4WD systems which splits power between the front and rear axles. Are you sure you don’t mean “torque converter” or “centifugal clutch”? A torque converter is the fluid coupled device which allows your automatic transmission to disengage without a clutch.
Anyway, I don’t know anything offhand about the torque characteristics of steam turbines. I would guess that they are similar to gas turbines, and I know that there are design problems with turbines in that they don’t change speed efficiently. I imagine that you would want some sort of decoupling between the turbine and the drive train to allow it to keep spinning while disengaged.