Mr Anderson,

Re: Durango. The railroad continues to fuel the locos with wood pellets at night as part of the agreed smoke mitigation process.

The pellets cost double that of coal.

See here www.livesteaming.com/chama.htm and scroll down.

Re: pre heating fuel oil to improve viscosity by injecting steam into the oil tank. This is done even on Kenya Railways and they traverse the equator.

Re: Steam locos being put out of service due to "pollution concerns" It is happening every day in China as they march towards a steam free country in time for the Beijing Olympics in August. (no the steam locos are not the issue but that is the program which is in place.)

TH

If I'm reading all the above discussions correctly, it appears that the biodiesel conversion has been removed from its experimental loco, IN PART because it worked TOO well.

Would it not be wise, from a PR, environmental, and economics standpoint, to construct, over time, an all-new loco series for Mt. Washington Cog, throwing almost all tradition out the window and approaching the problem anew with a new boiler designed for maximum BTU extraction, superheating, feedwater heating, clear stack, maybe even redesigned cog mechanisms.......

Send one coal-fired loco a day up (rotated from the "vintage" fleet), showing "this is how it used to be," and then send the rest of the day's locos up burning biodiesel and maybe even all the used french-fry oil from North Conway or the like?

Here's my $.02 for some suggestions for the next experimental period(s) at the Cog. Maybe these have been tried and failed.

1. Insulate the cylinders, live steam plumbing, and all boiler surfaces - fairly low tech and off-the-shelf supplies.

2. Install overfire air jets in the firebox (on a coal burner) - some consultation with and egineer, the boiler inspector, and some off-the-shelf supplies.

3. Design and start making adjustable valve gear for the following year's installation. In conjuction with this, assure the engine machinery is mechanically balanced as good as possible.

4. Contemplate compounding (with an automatic reducing valve for hills starts) if adjustable valve gear is unpalatible.

Also, a friend told me many years ago that when a good friend of his ran the Cog, he wanted to try superheaters, but Mrs. Teague didn't want to spend the money. I think that would would also have a great impact on the performance of the fleet, but require new sheets and equipment.

I am glad to see that feedwater heating is being done there. An injector can use a fair amount of precious steam when it is much needed in the cylinders as well as cool off the boiler unless throttled way back which inturn can wear out the nozzles. I am also glad to see that a huge smoke plume is not a prerequisite for a mountain climbing locomotive as we all know, smoke it unburned fuel. A number of years ago I saw for myself just how small a Cog firebox is and was amazed at how much coal could be consumed on such a small grate area in that span of time / distance!!! At another point another friend an I were talking with an engine crewman on a side track near the station about some engines smoking more than others (one had recenlty left the station with relatively little smoke). He said one or two fireboxes are a little different size and it also to a degree, the fireman.

The Cog started with buring wood 130 years ago, then transitioned to coal. If the appetite is there, oil in some fomulation could follow suit.

Finally, from the article I am unclear as to the source for their biodiesel, and exactly what is it that they are calling biodiesel - 100% converted fryolator oil, or DF2 with some plant oil?

No doubt there is much that can (and hopefully will) be done to improve the Mt. Washington engines.

Regarding questions about the fuel used, here's a link to the fuel supplier for Mt. Washington, Proulx Oil and Propane (see decal on fuel tank in one photo), with info on their biofuels:

http://www.proulxoilandpropane.com/cont ... ioheat.cfm

According to their webpage, their bio-heat fuels contain only 2 to 5% soy oil.

I think many will agree that the Cog's efficiency challenges are (1) boilers and fireboxes that are too small, and thus force fired wastefully, and (2) lack of expansive working (indeed the exhaust pressure is so high they have a bypass valve to vent steam directly). The boiler dimensions are limited by clearances and the need to incline the boiler. Expansive working is complicated by the method of braking - cylinder compression. Also, the engines are climbing at full torque most of the time, so expansive working is limited. Compounding similar to a logging malley is really the only option. If they could find the space, maybe making all (4) cylinders tandem compounds.

Steven,

I wouldn't necessarily agree that the boilers are too small. A lot could be done to the engines to use the steam that is produced more efficiently so the boiler demand is reduced. The Lempor exhaust and feedwater heater added to No. 9 by Nigel are major steps in this direction. As mentioned earlier, thorough insulation of all those exposed piping and cylinder surfaces (which is especially critical on a saturated steam engine) would be a big help.

Variable cutoff is an obvious additional step. I'd think that if you're exhausting so much steam you have to by-pass the exhaust nozzle, you could certainly hook up the valves without the engine coming to a screeching halt, even on the grades they deal with. Compression braking can be done with variable cutoff; the SLM rack engines used in Europe have both.

Superheating would be an obvious addition to improve efficiency and reduce the load on the boiler.

The unique layout of the engines on the Mt. Washington locomotives would seem to make them especially suitable for compounding. You've got four external cylinders which are locked in synchronization by the rack gearing. Compounding's benefits may have been debatable for high speed work, but for mountain slogging it proved its worth on the N&W. Then again, compounding is an additional level of complication that may not be necessary or desired.

No doubt Mt. Washington has a limited (very limited?) budget for locomotive R&D, but it looks like their investment in No. 9 has worked out well so far. Hopefully they'll continue with this work in the future. There's no compelling reason to strictly limit yourself to 1890's technology when ~118 years of steam improvements can be applied while maintaining the same basic machine.

If we consider the cog engines to be used like marine engines or stationary engines - running at a fairly constant speed and output when climbing - we ought to be able to fine tune them better than engines on flat railroads that run at many different speeds hauling many different rages of load on much more variable gradients and curves.

BTW, a disk brake was another improvement to Vicky.

dave

Dave,

That's a very good point. One thing that brings to mind is that you might not need true variable cutoff valve gear (Walschaerts or whatever). Something with two positions like "start" and "run" (set at maybe ~50% cutoff) as was used on the some of the earliest steam locomotives would do the trick.

I am enjoying reading the discussion here on the possible ways to increase efficiency of the cog railroad locomotives, but I am still not convinced that this has anything to do with efficiency but rather environmentalism, and how much of an impact may it have on the future of steam in this country.

If this thing was really a quest to improve cost efficiency of running a steam locomotive up the cog, would biodiesel really be the best option.

Mechanical efficiency is one thing but the bigger question to ask is cost efficiency. From some rough googling it seems to me that not including transportation, Coal tends to cost about $2/million BTU, while Biodiesel with out road tax seems to be around $16-17/million BTU. Are these numbers approximately correct?

While us engineers may indeed be concerned with efficiency of combustion, the ultimate thing that matters is cost efficiency. "How many dollars of fuel is needed to get me up the hill?" I am really curious whether or not Biodiesel lowers the end costs. My impression from reading that article was this was less about cost effectiveness/efficiency and more in the "Go Green" spirit.

As has been pointed out before I hardly believe that the 150 or so steam locomotives in operation in this country make up even the slightest of sliver of the problem, as CO2 emissions or any other coal emissions are currently defined. However with big black visible plumes (while arguably the black carbon being emitted has the least damaging environmental effect) I just fear that the little guy running the steam locomotive may be the easiest to pick on. I always am amazed to watch the news and see them talking about power plant CO2 emissions. Often you see this emotional photo of white steam belching from the cooling tower, the reporter points to it and talks about the CO2 escaping right behind them, (little do they know what they are pointing to is water), mean while no where in the picture can be seen the clear flue gasses emerging from the stack where the CO2 can actually be found! Perhaps, black smoke is even more frightening to these people, could we have a major image problem on our hands?

As to the plume of black smoke, sure it is wasted carbon content energy but if it costs 1/8th the price, per BTU how much money are you really throwing up the stack? Is it that significant? (I am curious, I have no clue.) At Mt. Washington, how do they get their coal to the railroad, and how much do they use each year? I am assuming it must need to be trucked in, so the cost of that could indeed be quite steep.

So here's the question quite bluntly, what is the motivation here, is it saving money, or is it environmentally friendly appearance?

As to efficiency for some of you who are involved with the modern steam projects. One thing I have noticed in reading in the past some of the new steam locomotives built in Switzerland I believe is that they all burned liquid fuel. A while back I remember even reading a whole paper online that compared the costs with running modern steam to diesel for tourist railroads and if I remember correctly their numbers came out with steam being highly competitive, with the steam engines burning fuel oil. What was the reason behind the choice of fuel. I would guess that the swiss alps if I recall was where they were running such engines may not be as coal rich?

If one were to attempt getting best cost efficiency, and was located close to good sources of coal, oil and biodiesel which would be the best choice?

Adam

Adam,

You certainly raise a good point. I think it's a pretty safe bet that coal is the cheapest fuel to move trains at Mt. Washington, but I'm sure there are other factors besides "environmentalism" involved. Of course, if they find a local source for waste cooking oil (WCO), their fuel costs for the oil-fired engine might be zero!

Note that Nigel did step-by-step modifications on No. 9 over several years. The last of these modifications was the addition of oil firing. Even though No. 9 has reverted to coal firing it is significantly more efficient and likely more powerful than the other locomotives irrespective of the fuel used.

Mt. Washington unsuccessfully attempted to produce oil fired conversions at least twice previously (once in the 1940's and once in the 1980's IIRC), before environmentalism would have been a concern. Oil firing would be cleaner and would require less labor for fueling and firing the engine, and there's no requirement to dispose of ashes. Judging from the cleanliess of combustion, the oil-fired engine should be capable of developing significantly more power than the coal-fired version. Maybe Mt. Washington is looking for operational convenience or maybe they're just covering their bases in case they're forced to get rid of coal at some point in the future.

All the new (mid-1990's) SLM rack locomotives in Switzerland and Austria are oil-fired, but I'm sure the choice of fuel was mainly for convenience as well. Some of those railroads also have older SLM (pre-WWII) coal-fired rack steamers which are used at least occasionally. The new oil-fired steamers are actually burning home heating oil which is not taxed at the same rate that diesel fuel is, even diesel for off-road vehicles, is taxed. This fuel cost difference made the new steamers competitive on a fuel cost basis compared to relatively new diesels in the same service despite the better efficiency of the diesels. A significant benefit was that ridership went up significantly due to the attraction of the steamers.

Let's also not forget that diesels lose efficiency at high altitude. Turbochargers can help ameriorate that effect to some extent. The SLM steamers burning light oil fuel emitted less harmful gases than the diesels, except for one - don't have the paperwork in front of me or I could tell you which.

The drawback to the SLM locomotives was initial cost or the cost of acquisition capitalization. Circa 1993-4 I could do 10 overhauls of old steam for the cost of buying one new SLM. Hard to justify that in that era economically.

dave

To really work this out, however, we would need to do a REAL comparison. My assumption, based on the amount of "clag" I see from the coal Mt. Washington locos, is that they are horribly inefficient at converting coal BTUs to motion, whereas the rebuilt #9 with biodiesel was more efficient--but probably still not as efficient as a properly engineered solution to the problem, starting from scratch. (Of course, we'll disregard a biodiesel internal-combustion engine propulsion, if only for tradition's sake.) In excursion terms, this would be like the Strasburg downgrading from the "overkill" of 2-10-0 90 to a more appropriate 2-6-2 or 2-6-0, or the Grand Canyon going to a bigger loco and declaring the 2-8-0s inadequate.

Mt. Washington has seemingly one standard route and operation and one fixed car loading (as opposed to trains). You couldn't ask for better parameters for reverse engineering.

Good point on the diesel vs. steam power at altitude.

The "harmful gas" in question is carbon dioxide, which is simply a result of the steamer burning more hydrocarbon fuel than the diesel does. The steamers emit much less carbon monoxide and oxides of nitrogen than the diesels.

Of course the thinking with biodiesel (at least with 100% soybean oil or similar) is that there is no net "carbon load" to the atmosphere. The plant matter can be processed to produce fuel which is burned causing the production of so much carbon dioxide, or the plants can be allowed to grow, die and rot in which case the same amount of carbon dioxide is given off.

Dave, do you think the cost factors have changed appreciably in the last ~15 years? I doubt new DLM locomotives would be any cheaper, but has the cost of the overhaul of an old steamer risen dramatically?

>Sensible environmentalists (we need more evidence of their existence)>would not object to historic steam operations for the same reason >California exempts classic cars from smog -- there are simply too few of >them to have a significant impact.

Speaking of California and environmentalism, I was told by an employee that the reason the Napa Valley Railroad repowered FPA4 73 with an EMD 645 and converted it to propane was to have a response to anyone who tried to legislate the 251 powered tourist train into extinction due to the billowing smoke from the Alcos. It may never come to that, but this is evidence that some operators are aware of that possibility and some are taking preemptive action.

I am also remided of the pioneering efforts at propane fueled vehicles in California. All the State did was mandate the reduction of propane's octane rating to such a low level as to render it a waste of time and money as an alternate fuel.

Hugh - the regulations have been overhauled since, as we all know - and the requirements for testing and documenting (not to mention the required work discovered) have certainly driven up the overhaul cost, predomiantly for boiler work.

Which makes one think about cost of replacing old boilers with new, having better combustion engineering and efficiency organically designed into them a more likely prospect. Running gear is running gear pretty much still, at least in my experience.

What could tilt the balance a bit more is cost for insuring new VS old boilers, should that arise, as well as the aforementioned environmental considerations. Fuel is still too miuch a marginal cost relative to others that small gains in efficiency won't pay for a lot of new hardware.

Once cost to repair an old boiler reaches maybe 75-80% of building a new one incorporating modern advances, I'd find it hard to justify retaining the old one in service. Greater long-term reliability and designed gains in efficiency would trump a little more short term investment from my POV.

No idea what DLM might want for a nice 3 foot gage 2-8-2T these days.

dave