There seems to be a lot of talk of using steam in the modern era because of its ability to use solid fuels, but what I don't is why use a steam locomotive to do that when other forms of external combustion engines can do that such a stirling engine or gas Turbine engine would offer better power to weight ratio and much higher efficiency. Not only that a steam engine requires a good source of water while other forms of external combustion don't. Just my take on it though.
Railroad to Freedom
I'm not sure that many people are talking about bringing back steam locomotives for everyday use?? Some folks have pointed out that US coal reserves are expected to last 200-300 years, while oil supplies are likely to become scarcer within this century, making coal-burning an alternative to burning oil products. If we had built electrified mainlines (or maintained the electric rail systems we once had) we could use coal and natural gas to generate electricity, so would be less dependent on oil for diesels.
Also, a gas turbine does not burn coal and it is an Internal combustion engine.
wjstix I'm not sure that many people are talking about bringing back steam locomotives for everyday use?? Some folks have pointed out that US coal reserves are expected to last 200-300 years, while oil supplies are likely to become scarcer within this century, making coal-burning an alternative to burning oil products. If we had built electrified mainlines (or maintained the electric rail systems we once had) we could use coal and natural gas to generate electricity, so would be less dependent on oil for diesels.
Just turn the coal into clean synthetic diesel fuel for around $60/barrel and be done with it. No need to spend $ Billions on electrified lines, when you already have locomotives with electric transmissions.
"Why modern steam?" Well, why not? Sometimes me lads you just have to put your feet up, pop a cold one, and enjoy "the stuff that dreams are made of..."
Sorry about that I didn't realize a gas turbine wasn't external combustion. Anyways a stirling engine would do a fine job of burning coal and you could use it as a electrical generator. Some one else mentioned the coal to oil method, that could work too
Breakout the perpetual motion machine!
Never too old to have a happy childhood!
BaltACD Breakout the perpetual motion machine!
Hey, why-ever not? "Stuff that dreams are made of." Just like me hooking up with Jenny Agutter. Man, I was crazy about her back in the 70's.
What does a remark about a perpetual motion machine have to do with anything?
Steam locomotives were not perpetual motion machines in any shape, way, or form. They used (large amounts) of various types of fuel, generated heat in their fireboxes, raised steam, and produced mechanical motion to perform useful work moving people and goods around for the better part of a century.
There are a variety of social, economic, and technological reasons why it is unlikely that steam locomotives are coming back in a major way any time soon. On the other hand, world society could reenter a Dark Age resulting from a resource collapse (the Greek Dark Age was really dark from that standpoint whereas the post-Roman Dark Age was probably a social construction of later people who thought themselves to be so much smarter). It is conceivable that the post-Dark Age society could construct steam locomotives in building itself back up. Steam locomotives don't violate any laws of physics; they only seem to violate some laws relating to how our society is constituted.
With respect to coal-fired gas turbines, I believe the direct combustion of pulverized coal in a gas turbine was tried, and it didn't work out well in terms of erosion and slag formation on the turbine blades. You could, however, put coal into a gasifier and power a turbine with the low-BTU gas. The electric power companies are looking into this, kind of dipping their toe into the pool as it were, as there are probably many technical details on this to work out. Also, a locomotive is still more limited in weight and space than a stationary power plant. But there is nothing in principle, no law of physics ruling out perpetual motion, that would stand in the way of a coal gas-producer gas turbine.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
So in essence, you agree that a gas turbine will not not, in practical terms, run on coal. If the coal must be "gasified" then it is not running on coal. And in any case, a gas turbine, running on coal, liquid fuels, gaseus fuels, or what ever IS an internal combustion engine.
Decades ago, there was a feature in TRAINS titled "Did we scrap steam too soon?" and, if I remember correctly, the answer was no.
There had been many attempts to increase the efficiency of steam locomotives, from better insulation of boilers to steam turbine drives and even steam motors - they all could not improve it anywhere near to the efficiency of Diesels or Electrics. The operation of steam locomotives always remained a fairly "dirty" operation, requiring a much higher number of personnel and short intervals between maintenance stops. What was the longest daily run of a steam loco in the hey days of steam, before it required servicing? Could not have been much more than 300 miles. Today´s ICE trains in Europe have daily runs of three to five times that figure, with only one engineer in the cab, not two.
As much as we steam buffs would like to see the resurrection of steam, it is most unlikely in whatsoever form, even if the world runs out of crude oil as the prime source of energy. In that case, it would be more economical to turn the remaining fossil fuels into electricity and string wires over our rails.
The advantage of electricity is that it is manufactured. As energy technology evolves there is no need to update every vehicle or every section of track. You can manufacture electricity in a nuclear power plant but the general public would never tolerate a nuclear powered train traveling through their city regularly. Electricity can be manufactured using hydro dams, wind mils, solar panels, coal fired plants, gas fired plants, fuel oil fired plants, nuclear plants, and who knows what else will be discovered in the future. Maybe someday we will be able to capture lightning. Electricity is not an energy source, it is a very versatile energy distribution system.
Dave
Lackawanna Route of the Phoebe Snow
Paul Milenkovic wrote the following [in Part ]:
"...With respect to coal-fired gas turbines, I believe the direct combustion of pulverized coal in a gas turbine was tried, and it didn't work out well in terms of erosion and slag formation on the turbine blades..."
UPRR # 8080 [nee:#80] was a platform built on an ALCO PA body, a GNRR W1 electric locomotive chassis, and a Centipede tender. It was said that its problem was that due to its pulverization of the coal for fuel was not uniform, and therefor was a danger to anyone standing in its area as the larger pieces of coal would cause the turbine blades to fly out of the unit like shrapnel.
The PRR had their more conventional Turbine (a 6-8-6). It lasted about 5 years in service, and was scrapped in 1952. Its' problem was under performance at speeds under 40 mph.
It would seem that modern advancements in the more uniform pulverization of coal and modern turbine technologies would be useful in a more modern steam turbine locomotive.
In Europe there were a number of different models produced to utilize steam and turbine technologies, but I think the results were sometimes good and sometimes not so.
The S2 (PRR 6200) and UP 80 were two completely different turbine designs. The only thing that they had in common was that they burned coal for fuel. The S2 was a steam turbine and was similar to marine designs. UP 80 was a gas turbine that burned coal instead of Bunker C.
ontheBNSF There seems to be a lot of talk of using steam in the modern era because of its ability to use solid fuels, but what I don't is why use a steam locomotive to do that when other forms of external combustion engines can do that such a stirling engine or gas Turbine engine would offer better power to weight ratio and much higher efficiency. Not only that a steam engine requires a good source of water while other forms of external combustion don't. Just my take on it though.
I wouldn't say there's a lot of talk in the railroad industry, but there is, occasionally, on these and other railfan forums....
One modern proponent is Thomas Blasingame, who has been proposing modern steam electric designs for a couple of decades now which would burn coal and other solid fuels (he specifically mentions fuel made from municipal waste).
A summation of his proposed locomotives, along with responses from Amtrak, the FRA, and Norfolk southern, can be viewed here(in PDF format):\
http://docs.stb.dot.gov/?sGet&Dl5YTH1WXw1zAAsKXBdSV0x6Sw1xfAMJXAEGCW4DF3MBe3ILXwgCCmYHGAYDfxVaAlxGcUsOS1FELBVJO1RES0ZcQQ0AfQcMS1dfVEpdTl1VcAEIVAYCCQoBamB0C20xNjgvMy8wME0zOQw%3D
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
Maybe YOU said that turbine blades would fly out like shrapnel but UP and GE said that it was erosion and deposits. There is also the issue of ash disposal as blowing it out the exhaust is not likely to make a lot of points these days. The PRR was a steam turbine. Apples and oranges.
I agree lets enjoy the idea of a modern steam locomotive .
Sir Madog ... What was the longest daily run of a steam loco in the hey days of steam, before it required servicing? Could not have been much more than 300 miles...
... What was the longest daily run of a steam loco in the hey days of steam, before it required servicing? Could not have been much more than 300 miles...
It's longer. Check out the thread about "Steam long distant operation", also under Steam & Preservation.
Gas turbines do offer better power-to-weight ratios. However, their efficiency and power curves are very peaky. As soon as you move off-peak, fuel consumption rockets and power plummets. Hence, gas turbines favour continuous running at fixed speeds (except for aircraft, where power-to-weight ratio dominates for obvious reasons). The UP devised some famous gas turbine - electric locomotives. I presume the thought was that long-haul freight over the steady climbs of the UP mainline would favour the gas turbine's performance characteristics. They were still thirsty though, as gas turbines of the day were relatively inefficient. These days, efficiencies have greatly improved due to higher operating pressures & temperatures.
Gas turbines have been powered using all sorts of liquids & gases. And yes, even pulverised coal has been used, although the ash from the coal had a tendency to block cooling holes in the turbine blades. This of course reduced blade life and could lead to blade failure (not an event you would want to happen, as blades have been known in the past to puncture through gas turbine casing and cause serious damage to anything and anyone nearby, although these days gas turbine casings are designed to contain such failures reliably).
Gas turbines have been designed to be external combustion engines whereby the fuel is burnt in a separate system, and a heat exchanger used to transfer the energy of combustion to the gas turbine.
I have no experience of Stirling engines. I think they too have peaky performance, but are very efficient. They like very steady running conditions. Any power-to-weight benefit can sometimes be lost in bigger designs due to the need for bulky heat management equipment. They also take awhile to start up.
As for resurrecting steam, who needs an excuse? They look, sound and smell great! Plus, I imagine it's a fascinating engineering challenge - how to improve efficiency, reduce emissions and retain that simplicity.
Regards
http://en.wikipedia.org/wiki/Stirling_engine
people keep forgetting about the stirling engine. This seems like a possible solution as it is external combustion and unlike a steam can achieve high efficiency, but of course they take a while to start up.
Steam is only second in power to nuclear. Nothing else comes close between those big two. Steam can be built up to a psi indefinitely as long as you can keep the fire hot enough. Steam may not be very efficient but neither is diesel engines with a efficiency of around 30%.
I read the business section everyday and I think all this talk about bringing back steam has to do with the high price of a barrel of oil. The economy has fallen off a cliff yet the price of a barrel of oil is 90-100 a barrel. Once the economy roars back to life again the price of a barrel of oil is going to climb into record territory going way past $200.00 for a barrel of oil. As it stands today a gallon of gas is somewhere around $4.00. It will probably go to $6.00 or $7.00 when the economy gets better. That price is unsustainable for anyone who deals with transportation.
The United states does have one of the largest coal reserves on the planet. Cheap clean coal and steam locomotives for power. Fire and water is the answer.
Nuclear power is just steam generation using a different type of heat source, a controlled nuclear reaction instead of coal, oil, natural gas, etc.
As far as the price of coal, if railroads returned to steam locomotion, this would greatly increase the demand for coal and consequently drive up the price. Also to be considered is the cost and energy involved in maintaining the supply chain (much of which no longer exists) for a solid fuel. Also to be considered are the various EPA regulations concerning the burning of coal, PRB coal may be relatively clean but other sources are much less so. Also, fitting scrubbers to steam locomotives may be impossible.
For a variety of reasons, a return to steam locomotions just isn't going to happen and wishing won't make it so.
CSSHEGEWISCH Nuclear power is just steam generation using a different type of heat source, a controlled nuclear reaction instead of coal, oil, natural gas, etc.
While that's true for central station generating plants and naval nuclear propulsion, there have been proposals for gas turbine cycle power plants (General Atomics HTGR-GT) along with nuclear gas turbines for aircraft nuclear propulsion. Then there were the nuclear rocket engines (NERVA) and nuclear ramjets (Project Pluto AKA Supersonic Low Altitude Missile).
The gas turbine would be my first choice for a nuclear locomotive as it would allow efficient operation with a high heat reject temperature - or even simpler using an open-cycle gas turbine IF the core could be as to not leak fission products or activated cladding into the airflow (same constraint as for aircraft nuclear propulsion). Economics and safety concerns make a nuclear locomotive extremely unlikely
- Erik
P.S. Nuclear power generation on a small scale (under 1kW electric) is usually done with a radioisotope thermal generator.
P.P.S. Heinlein's 1940 short story, "Blowups Happen", describes a U-235 fueled nuclear plant using a mercury topping cycle in combination with a steam cycle - it's amazing what he got right and what he got wrong was fairly subtle (though crucial).
The nuclear aircraft engines were shielded only enough to protect the cockpit crew. There was little danger from radiation at altitude. Even enough air will attenuate radiation. This would not be the case with a locomotive. Very heavy shielding would be required and to make it completely collision proof would be impossible.
Modern steam? Gentleman, I give you the Tornado! LEDs for headlights and a cab (I've been in it) full of computer equipment. It's nice to put your feet up and dream but the Brits make it reality!
Jenny Agutter? Nice, but I would dream of the 1941 version of Jane Russell but that's just me!
While the weight requirements for an aircraft reactor are more stringent than for a locomotive, both would have concerns for fuel cladding integrity when using direct heating of the air serving as the working fluid for the gas turbines. The shielding challenge for a nuclear locomotive is not weight, but getting an adequate neutron shield that will fit in the loading gauge.
Most critical aspect of collision proofing the reactor would be decay heat removal.
FWIW, the French generate more than 70% of their electric energy from nuclear and thus a alrge percentage of their rail traffic is nuclear powered.
- Erik ('78 MSNE UCB)
As far as a nuclear powered train is concerned I think we can all put it out of our minds. Ain't gonna happen, no way, no how. Can you imagine the screams from the people who are anti-nuclear power plants when they hear "Coming soon to a railroad near you, the new GE U-235!" My eardrums are shattering just thinking about it!
And to 54light15: Oh yeah, I've seen those shots of Jane Russell in "The Outlaw." Not bad, not bad a'tall, but a bit before my time, don't ya know. Jenny's a contemporary, a "Boomer" like me.
what about thorium http://energyfromthorium.com/
ontheBNSF A film showing the development of steam technology use in intercity transit buses. The results were similar efficiency to GM Diesel buses with much lower emissions. Three prototypes were produced. What I find even more interesting is that it required one to operate this, usually a steam engine requires someone to monitor boiler pressure. It was capable of being operated by a normal bus driver with no extra training. Anyways in a matter of months the developers of the project achieved what took the automotive industry years to achieve, essentially the researchers fixed the steam engine's flaws. The most interesting thing of all of this is that the steam is reused unlike older steam engines where the energy would be unused and not contribute to drawbar performance. A lot has changed in both the realm of internal and external combustion since the videos were made in the 70s but they are interesting none the less. Part 1 http://www.youtube.com/watch?v=blGTfgc0gpk Part 2 http://www.youtube.com/watch?v=ZbxZWThuYqo Some other modern steam implementations Steam ford falcon http://www.youtube.com/watch?v=LJq2Hc_mXFI Cyclone engine http://www.cyclonepower.com/
Not sure what you mean by "reusing steam". The whole looks pretty bogus when they call a turbine an "expander".
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