In “Harnessing the Iron Horse” (Grantville Gazette 7), I speculated about the evolution of the steam locomotive. My focus was principally on what might appear within the first decade after the Ring of Fire.

In this article, I will look further along the time line, at what might one day replace the steam locomotive. While Steam will be King in the 1630s, and for years beyond, there will be experimentation in the 1640s, and perhaps earlier, with alternative motive power technologies, and that will in turn affect how governments, investors, shippers and passengers view steam.

It may take one or more generations before these alternative systems become commercially significant, but their day will come.

First, let’s look at what fuels could be available, and in particular, what the oil situation is likely to be a generation after RoF. Then we’ll systematically review our power plant and transmission options, and finally we’ll consider the economic aspects of the choice among steam, diesel and electric operation.



Fuel is the food of the locomotive. The important considerations with fuel are energy/unit mass, energy/unit volume, cost, and more difficult to quantify factors such as safety and ease of handling.

The energy densities vary according to the number of C-C and C-H bonds in the molecules of the fuel, but here are some typical figures:






natural gas, uncompressed



natural gas, compressed to 3600 psi



liquefied propane






kerosene (jet fuel)



diesel, automotive






coal, anthracite



coal, bituminous



coal, lignite








peat briquette


wood (green)


wood (air dry)


wood (oven dry)


(Wikipedia/Energy Density, except wood: PHT)

Wood. For millennia, wood has been burnt to generate heat. Sweden, Norway, Finland, Russia, the Baltic states, Bosnia-Hercegovna, and parts of Germany, Austria and Hungary are heavily forested. Cooper, “The Wooden Wonders of Grantville” (Grantville Gazette 13). The United States and Canada are well-endowed with trees, as is evidenced by the extensive use of wood-burning locomotives for much of the nineteenth century. There are also extensive forests in Central and South America, southeast Asia, Japan, Korea and Siberia, and more limited ones in central Africa, the Himalayan foothills and Deccan plateau of India, and on the periphery of China.

The wood used as fuel needn’t be wood that is of value as a structural material (or anything else). In Bolivia, resinous shrubs (yareta) were burnt. (Messerli 174).

Organic waste. 1911EB/Fuel mentions the use of “cotton stalks, brushwood, straw, and the woody residue of sugarcane” as fuel, especially for raising steam. In France and Germany, spent tanners’ bark was used to some degree. The dried dung of camels (Egypt), oxen (India), and llama (Bolivia) have also served as fuels.

Coal. From highest to lowest rank (in energy density), we have anthracite, bituminous, sub-bituminous and lignite. In the nineteenth century, a grade between anthracite and bituminous, called “steam coal,” was recognized. In addition, note that peat, a precursor to coal, can be used as a fuel. In terms of heating capacity, the general rule is that 2,000 pounds of coal is equivalent to 5,250 pounds (1.75 cords) of wood.

Not that a coal-fired steam engine made particularly effective use of the chemical energy of coal. One pound of good coal in the firebox yields about 15,000 British Thermal Units (BTUs) heat energy, of which 50–80% is transferred to the water. When the steam is released from the steam dome into the cylinders, about 7–11% actually does work (i.e., moves the pistons), and the rest escapes. So the overall thermal efficiency is only about 6% (900 BTU per pound of coal). (EB11). Some sources cite even lower values.

There are major coal fields in modern Germany, England, Belgium, France, Russia, Siberia, the United States, Canada, China, India, Australia and, to a lesser extent, Japan. On the other hand, Scandinavia, the Mediterranean countries, Africa, the Ottoman Empire, Mexico and South America are relatively deficient in coal. Coal is heavy, and it can only be transported economically by sea or by rail.

As a result of the RoF, Germany’s natural bounty of coal has been augmented by Grantville’s coal mines. Not only is there a considerable amount of coal within the Ring, the miners have up-time equipment for mining it very efficiently. This of course gives all transport technologies that can utilize coal a big boost.

Coal Dust. Diesel’s original idea was to use coal dust as diesel engine fuel (Germany having a lot more coal than oil.) There would be expenses associated with drying, pulverizing and sieving coal, but presumably it would still have been less expensive than imported petroleum.

The coal dust was deemed unsuitable after experiments in 1899. (Wells 77). “He observed high wear and accumulation of deposits on the piston and cylinder wall. He ceased working on the concept after an accident (possibly a coal dust explosion) occurred during operation on coal dust.” (ADL 2).

The coal dust worked best when the coal was mixed with the air during the suction stroke of the air pump, and this mixture compressed with a bit of liquid oil to make ignition easier. (Wells 78). Even so, there was a problem related to accumulation of a coating of powdered coal on the internal oiled surfaces of the cylinder. Hence, to use coal dust as fuel, the engine needed a separate combustion chamber. It was concluded that liquid fuel was available at a good enough price so that it wasn’t worth continuing to pursue coal dust.

Every decade, the idea gets dusted off again. (Groan!) It’s believed that in Diesel’s experiments, and in later ones conducted during WW II, the coal dust had 10–20% ash and particle sizes of 75–100 microns. There were problems of sludge accumulation, nozzle blockage, and engine wear (35 times normal level in piston rings and cylinder liner).

More recent experiments have had better luck, using slurries of, e.g., 12 micron coal particles in a 50:50 coal-water slurry. (Some coal combustion serving to evaporate the water.) It was still necessary to “harden” the injectors (Cooper-Bessemer used ceramic; General Electric (GE), diamond; Little, diamond, silicon carbide or tungsten carbide), piston rings, cylinder liners and valves. In 1991, a fully modified 2500hp diesel locomotive was run on the GE test track. (; Wald). The GE work was under contract with the Department of Energy’s (DOE) Morgantown, West Virgina Energy Technology Center, so there’s a possibility that up-timers in Grantville knew about it.

The materials technology necessary to make coal dust-fired diesels work is probably several decades down the road, but it does mean that we have another alternative to conventional diesel fuel.

Liquefied Coal. Liquid fuel does have certain advantages, and coal can be converted into liquid hydrocarbons by the Bergius hydrogenation process or by the Fischer-Tropsch (FT) process (which first converts the coal to a synthesis gas, a mixture of carbon monoxide and hydrogen, and then that to hydrocarbons). The latter process was used by Germany in World War II (when it was blockaded) and by South Africa (when it was ostracized). FT has high capital and operating costs. It would of course take time and money to reconstruct these processes and it would result in a more expensive fuel.

In 1996 it was calculated that crude oil prices had to be at least $35/barrel for FT fuel to be competitive. (Choi); the oil price was then around $25/barrel. And before you made the capital investment, you of course wanted to be sure that the oil price would remain well above that breakeven point long enough for you to recover and make a good return on your investment.

Raw Coal Tar. This is the water-immiscible residue from the pyrolysis of coal to produce coke or illuminating gas. It was for many years considered to be a waste product, and was used as a secondary fuel under the retorts that produced it in the first place. In Paris, 1830, it sold for 8s/ton, probably mostly for use in waterproofing (Lunge 21). The invention of the coal tar dyes increased the value of coal tar, and in 1883 it sold for 55–63s/ton, dropping to 7s/ton in 1886. (22). When the price was on the low end, or the gas-works or coke-oven was too far from the tar-distiller, it was still burnt. (Lunge 322).

To achieve complete combustion, the tar may be atomized by a steam jet (325), and other tar burner designs were developed in the nineteenth century. The heating value of coal tar is about 37–45% that of coal (329).

Gygax (1446) says that “Many experiments have been made with raw tar as a Diesel engine fuel which have proved conclusively that tar can be used successfully in the ordinary diesel engine,” but only “vertical retort” tar has a sufficiently low free carbon content to be suitable.

Coal Tar Oils. It is also possible to use “coal tar oils” as diesel engine fuel. These are distillates (at least 60% distilling at 300oC) from coal tar (including tar from gas works and coking plants). In 1913, “in Germany and France, the majority of middle sized and large Diesel engines run on tar oil.” At the time, Germany was producing 1,400,000 tons of tars, and 400–450,000 tons of tar oil, of which 120,000 could be used in a Diesel engine. The total consumption of Diesel fuel was then 75,000 tons. (Gygax 1450).

It appears that a light oil was blown into the cylinder ahead of the tar-oil charge; it caught fire first and ignited the heavier tar-oil (Morrison 250). However, Morrison doubts that this method would work in an engine faster than 200 rpm. So this might be inadequate for locomotive diesel, but it could be used in a marine engine and therefore free up some conventional diesel fuel for locomotive use.

Tar oils may be made from lignite, not just from bituminous coal. There was significant use of lignite tar-oils as fuel in early twentieth-century Germany. (Gygax).

Naturally, “coal tar oils” may also be burned under the boiler of a steam engine.

Oil. The principal oil regions are in Galicia, Romania, the United States, Canada, Mexico, Venezuela, Russia, the Middle East, and Indonesia The remaining European countries are poorly endowed with oil. Oil can be transported by sea, by rail or by pipeline.

Crude oil is refined into various fractions, notably gasoline, kerosene (jet fuel), diesel oil, fuel oil, lubricating oil, and asphalt. These are differentiated by distillation temperature, viscosity, and cetane number (ignition delay).

It’s important to note that the distillation temperature ranges for gasoline (122–374o F) and No. 1 diesel (300–575o F) fuel overlap. Where they overlap, gasoline and diesel consumers are in competition for the supply of that “cut.”

However, if the demand for gasoline encourages increased prospecting, drilling and production, it will have the side effect of making more No. 2 diesel (distillation 500–640o F), or heavier oils, all unsuitable for gasoline use, available. And in a like manner, if there is increased demand for diesel, that will “pull” more “light gasoline” onto the market.

In early twentieth-century America, the price of diesel fuel was only about half that of gasoline (SolomonADL 34).

The ideal diesel oil for a diesel engine is dependent on engine speed, with low speed engines such as those on ships favoring heavy, high viscosity oils (no. 5 or 6), and the high speed engines of autos, trucks and buses desiring light, low viscosity oils (no. 1 or 2). Locomotive engines prefer intermediate oils. (Sivasankar, Engineering Chemistry 372).

Petroleum Residues. These are the liquid and solid residues of crude oil distillation, and are a considerable proportion (over 50%) of heavy crudes, such as the shallow Wietze oil or that of Baku. At Baku, they are called “massud,” and have a heating value nearly twice that of coal, one pound raising 12–15 pounds steam. The petroleum tar is atomized with steam in a “forsunka” burner. (Lunge 329). Gygax (1455) says that residues containing up to 46–48% asphalt (the material left behind after distillation to 350o C) “have been used successfully as Diesel engine fuels.”

Natural Gas. As of the RoF, some Grantville vehicles and installations are powered by natural gas. Flint, 1632, Chapter 8. Others are converted to run on natural gas, post-RoF. Jones, Anna’s Story (Grantville Gazette 1); DeMarce, “Second Thoughts” (RoF2), Howard, “A Gentile in the Family?” (Grantville Gazette 19). A tram is running on natural gas as of early 1634. Zeek, “The Minstrel Boy” (Grantville Gazette 15).

Natural gas is practical as a vehicle fuel only if compressed (CNG) or liquefied (LNG) to increase its energy/volume ratio. Chad Jenkins realized this fairly early, and cornered the market on pressure tanks and their connections, which were the initial limiting factor insofar as natural gas conversions were concerned. Rittgers, “Von Grantville” (Grantville Gazette 4). Of course, both compression and liquefaction require energy.

Grantville has natural gas, but its real-life counterpart, the Mannington field, is not a major field. The largest natural gas field in Europe is the Slochteren field, near Groningen, in the Netherlands; it was discovered before WWII. There are two major fields in Norway (Ormen Lange and Troll), and at least three in western Siberia (Yamburg, Urengoy, Medvezhye). The Groningen field is mentioned in “Grantville literature” but I am not sure about the others.

The most economical way to transport natural gas over long distances is by pipeline. However, CNG or LNG can be transported in railroad tank cars, etc. My expectation is that at least up to 1650, natural gas will be exploited only within driving distance of Grantville.

Biofuel. A biofuel is one derived at least in part from living organisms. Biodiesel, in turn, is the biofuel equivalent in distillation temperature and viscosity of petroleum diesel.

One option is to ferment the carbohydrates in plants (wheat, corn, sugar beets, sugarcane, potatoes, etc.) to alcohols. (Destructive distillation of wood will also produce alcohol, and it can be applied to wood that isn’t useful as a structural material.)

A second option is to use vegetable oil or animal fat. In 1631, Ed Piazza tells Mike that you can run diesel engines on vegetable oil, but that it would take until the next year to make it in quantity. Flint, 1632 (Chapter 11). Note that in OTL, whale oil was used as an illuminating fuel. However, McDonnell, “How to Keep Your Old John Deere Plowing: Diesel Fuel Alternatives for Grantville 1631–1639 (Grantville Gazette 4) identifies cod liver oil as the most economic raw material.

In general, the component molecules of vegetable oil are fairly high molecular weight, making for a viscous fuel. The molecules can be degraded to make them more suitable for fuel use.

A third option is to incompletely burn plant material, resulting in a syngas (carbon monoxide and hydrogen).

Hydropower. This is relevant only to railroad systems with central power plants. The power generated is dependent on the elevation change and flow rate of the rivers, so mountainous areas with good precipitation are favored. (Within Europe, the countries with rivers whose energy could be harnessed include Norway, Sweden, Russia, Germany, Switzerland, France, Italy, Spain and the Ottoman Empire.) Even so, quite expensive engineering works might be needed to dam rivers, protect towns and farmland from flooding, etc.

There is no guarantee that the dam will be near the railroad line. Hence, it might be necessary to transmit the power over a greater distance than would be necessary with a coal- or oil-fueled plant (the railroad could be used to bring coal or oil to such a facility, if need be).

Water power, by its nature, tends to fluctuate. Therefore, it’s necessary to have a reserve power plant to fill in the gap if the hydroelectric power supply is interrupted by drought or a freeze.


Fuels for Steam Locomotives. In OTL, steam locomotives burnt wood, coal, oil and occasionally more exotic materials.

The first American railroads to convert to coal were those which serviced coal fields. They were followed by railroads operating in the heavily populated northeast (where timber was cut down to make houses and furniture), or across plains or deserts. Eventually, the opening of large new coal fields persuaded even the heavily forested south to adopt coal. The American far west was coal-poor, so railroads in that area were eager to switch to oil burning after the big California oil strikes.

In general, a firebox design that was suitable for burning wood worked reasonably well with bituminous coal. However, one could use a less elaborate smokestack (because coal produced fewer sparks), introduce a firebrick arch (to force the gases into an indirect path, allowing for more complete combustion), and replace copper with wrought iron or steel (because the coal products corroded the copper). (Solomon ASL 29ff).

Anthracite burns slowly because of its lack of volatile gases, and hence is best suited to a broad shallow firebox.

Lignite has a low energy content, and thus you need a large firebox, with a large grate area, to get adequate power. Raw lignite is composed of small, light particles and hence throws out a lot of sparks, like wood. The lignite may be bound into briquettes but this adds to cost.

Oil provides a higher energy density than coal. As of 1915, despite Europe’s greater access to coal than oil, several railroads in France, Austria and England were “using oil fuel more or less extensively” (Gibbings 2).

Gibbings (8–10) has listed numerous advantages of oil over coal: reduction (at least in oil-rich countries) of cost (40%) and weight (30%) of fuel; can travel further without refueling); less manual labor in stoking and station management (pipes and pumps replaced shovels and cranes; at one station, two men were able to do the work formerly done by 26); no smoke, ash or clinker; rapid adjustment of fuel to load without waste; higher evaporative efficiency, elimination of losses (2–10%) due to weathering of coal; elimination of damages for setting fire to adjacent crops and properties as a result of sparks; more rapid steam raising (40 minutes); improved shed economics; greater shelf life.

To burn oil fuel, the firebox must atomize the fuel (convert it to a mist)(Gibbings 16), and this is usually done with a steam jet as disclosed in 1911EB/Fuel.

Oil Shortage or Glut?

We are going to be producing oil no matter what, since we need it for cars, trucks and aircraft. The question is, when will we have enough to use oil products in locomotives?

First, let’s look at the demand side. Historically, oil demand was at first just for illumination—the kerosene (later used as jet fuel) was the cash fraction and everything else was essentially waste. The automobile created the demand for gasoline, which is a lighter fraction. The lightest fraction was used by the chemical industry. In the twentieth century, heavier fractions were variously used as fuel oil in stationary power plants, ships or locomotives, or cracked to make gasoline or chemical feedstocks.

In the 1630s and 1640s, the demand for oil for fuel use may be limited by the number of engines available. At first the only engines will be the ones that came through the RoF, and then there will be a trickle of post-RoF builds.

Mannington, per the 2000 Census, had 1342 auto, vans and trucks kept at home for household use. To that you may add motorcycles, trailers, tractors, and government and commercial vehicles—call it 1500 total. It doesn’t much matter for purpose of calculating oil demand whether their engines are kept where they are or are re-purposed as marine or aircraft engines.

Only late model, high-performance engines are likely to be earmarked for aircraft use. Huff, “Aircraft in the 1632 Universe,” Grantville Gazette 12, assumes that a year 2000 auto engine would normally get 25mpg but, rigged as an aircraft engine, would only do half as well—thus consuming four gallons an hour. However, he also assumes that it will be running on M85, that is on a mixture of 85% methanol and 15% gasoline. I imagine that there are other engines that can be used with such a mixture.

Perhaps a quarter to a half of the Grantville vehicles are carbureted and therefore can be modified to run on natural gas.

We know that the coal trucks have diesel engines, some of which were re-purposed for use on the ironclads. It is canonical that the diesel engines in Grantville can run on vegetable oil. While supplies of that are no doubt limited, that still helps reduce the demand for crude oil.

I would imagine that even if gasoline were readily available there would be limits to how many miles the land vehicles would be driven. Initially, the only area with asphalt roads is the RoF, 6 miles in diameter. Canon does speak much about road construction but I have the impression that the amount of construction, in mileage, of good roads was not very high. The fifteen mile “luxury road” (graded and graveled, not even paved) built to bypass Forchheim in 1633 consumed the entire budget for road improvements in the prince-bishopric of Bamburg. DeMarce, “Bypass Surgery” (1634: The Ram Rebellion).

The number of new engines built in the 1630s is likely to be very small relative to the number that came through RoF. And of course there are going to be up-time engines that stop working, too.

Still, let’s say that we have 1500 vehicles driven an average of 10 miles/day, and getting 20 miles/gallon. Then the demand for gasoline would be 750 gallons/day. A barrel of oil is 42 gallons. The gasoline fraction varies from say 1–30% depending on the source. (The shallower Wietze oil is on the low side.) Let’s assume 10%, so one barrel of oil provides about four gallons of gasoline. And we would therefore need about 200 barrels crude per day to keep all 1500 vehicles running.

Of course, oil is in demand as an organic chemical feedstock, not just as a fuel. But that’s equally true of coal, and it’s at least plausible to assume that the supply of oil will not be exhausted by these non-fuel uses.

Railroad use is probably not going to add significantly to the demand. In 1980s Africa, which is not heavily industrialized, the oil consumption by the railroads is just a few percent. (Alston 35).


Now let’s look at the supply side. Oil supply is certainly going to increase, as we drill more producing wells. The production rate will accelerate because our prospecting and drilling efficiency will increase. If the price of oil is initially high (because of high demand) then of course that’s going to coax more investors into the oil industry.

In 1631–34, the supply of gasoline is clearly limited. In canon, we initially are collecting some condensate from gas wells in Grantville. By 1633, we are exploiting one German oil field: Wietze. The down-timers knew of the existence of tar deposits and oil seeps there, and the oil was sold as a medicine as early as 1480 (Clark 7). In OTL, a well (drilled looking for coal) struck oil at 200 feet on May 29, 1858. (Clark 25) Mining of oil-bearing sands began in 1917, so strictly speaking, we don’t even need drilling technology to obtain Wietze’s black gold.

The oil extracted by mining at Wietze was a heavy oil, more useful as a source of lubricating oil than of gasoline; gasoline content was under 5%. Corwith, “The Oil Mines at Wietze and Pechelbronn” (Grantville Gazette 23). I would expect that the drilled oil isn’t much better, certainly no better than 10%.

It’s possible to find light oils at Wietze; they are in Upper Triassic (Rhaet) rock at a depth of 330–350 meters. Find it, and almost 20% of production distills at under 250o C [482o F]. (Kauenhowen 480, 482). But in OTL, the light oil was discovered only in 1900.

Pechelbronn, which is in modern France, was added to the USE’s Upper Rhenish province by the 1634 peace treaty (Flint, 1634: The Baltic War, Chapter 68). It likewise has both heavy and light oil deposits. The light oils lie at 150–600 meters. (Rice 281). Pechelbronn production in 1950 was about 500,000 barrels of light oil annually. (Bateman 692).

While Germany does not have any giant oil fields, it has quite a few salt dome deposits like Wietze. Germany’s total oil reserves are sufficient to support USE military forces and industry for a long time. In 1880–1918, Germany produced about 17 million barrels. (Day 134), an average of 436,000 annually or 1194 daily. Just a smidgeon compared to the USA, but plenty relative to what the USE can consume in the near-term.

OTL, Wietze production (including mining) was 826 tonnes in 1892, 27,042 in 1900 (KKGG; Volkswirtschaftliche Chronik 23)(an average annual rate of increase of 55%). One metric ton is about 7 barrels, so in OTL 1900 we have 190,000 barrels/year, or 520 barrels/day.

There are several larger fields in Germany. In 1937–1993, the Reitbrook field (discovered 1937, first oil sand at about 750 feet, 1000 acres producing) produced a total of 15.7 million barrels of oil (average 280,000 annually). Nienhagen (discovered 1909) production mid-twentieth century was around 300,000 tons (2,100,000 barrels) annually (Ludmer 259; Tiratsoo 120ff; Pennwell 146). None of these would impress a Texan, of course!

The question is, how fast can we scale up the production rate of crude oil and, in particular, of gasoline and diesel fuel?

By 1635–36, it’s likely that there will be additional wells drilled at Wietze, boosting production. However, it’s less predictable that they would have found the light oil, and nothing in “Grantville literature” would have told the field management that in fact there’s light oil to be found.

Until we have a lot of drilling rigs, scale up will be slow. Wietze is a “Hanoverian” field, and in 1897, the 80 shallow wells in operation in that area averaged 20 barrels/day (Emmons 513). So each new well might add only 20 barrels/day to total production—and with Wietze heavy oil, less than 2 of those barrels will be gasoline. For a big increment, we need to drill deeper or start mining (for which “quantity has a quality all its own”). And I doubt the up-timers will know about the OTL oil mining at Wietze, so they will have to think of it on their own.

In 1950, Germany was producing about 4.5 million barrels annually (Bateman 692), but it will take decades to reach that level.

Developing new fields will help. But while Germany has many small oil fields, there are numerous reasons why an area that in fact contains an oil field might be neglected:

—we lack accurate information as to where to start looking.

—it’s too remote for it to be convenient to send prospectors or drillers, and it would be expensive to transport back any oil found.

—the members of our limited corps of geologically trained prospectors have been sent to more promising areas.

—if the locals aren’t aware of surface oil signs, and we have to map the surface geology to find favorable structures, it can be very time-consuming, especially in marshy or forested areas.

—the locals might not let us look where we want to look.

—the oil field may lack surface evidence of oil or even of favorable structures.

—there may be legal uncertainties as to who can grant the right to drill, or the owner may simply refuse for fear of disturbing agricultural activities, or the owner may have too high an opinion of the oil prospects and demand too much money.

—there may be a shortage of drilling crews or equipment, so we can’t drill everywhere we’d like to.

—drilling may prove too time-consuming, expensive or hazardous, because of very hard rock, “caving” formations, water infiltration or high pressure gas.

—we lack the resources (money, fuel, wire cable, drillpipe, casing) to drill deep enough to reach the pay depth.

—our exploratory well may be dry, discouraging further attempts in the same area for several years (even though we may be close to, or even nominally within, the bounds of an oil field).

—inept development may cause the early depletion of the field.

—the oil found isn’t worth the lifting cost (it’s contaminated with water or sulfur, it’s heavy, it costs too much to ship).

The bottom line is that since there’s a lot of luck in the oil business, Eric can justify an oil shortage or an oil glut, or even a fluctuation between them, as he pleases.


I have no doubt that there was, in the short term, a serious oil shortage as reflected in canon. But if we hit the light oil stratum at Wietze, or find another major field, gasoline and diesel fuel production could increase dramatically. To the point that we had a quite abundant supply of fuel, relative to transportation demand, at least until the number of “down-time” engines in operation exceeded the number of “up-time” ones.

I expect that by the 1640s, perhaps sooner, we will be producing light oil at Wietze, we will be mining heavy oil at Wietze and Pechelbronn, and we will perhaps have started development of additional Hanoverian oil fields.

Looking further afield, both Gustavus Adolphus and Albrecht von Wallenstein are expansionist monarchs, and they are probably both eyeing Galicia (southeastern Poland). In OTL, the Swedes invaded Poland (including Galicia) in the 1650s. Rail or pipeline transport would make it feasible to use Galician (or Romanian, if the Ottomans played ball) oil elsewhere in Europe. Consideration of the economics of pipelines must be relegated to another article.

Overseas oil is also a possibility. I anticipate several objections: (1) most of the oil is outside USE control; (2) it’s too risky to rely on overseas oil because it can be interdicted by an enemy navy; (3) it would be too expensive to transport it; (4) we will lack the tanker capacity to transport the necessary quantities (5) we don’t have access to suitable port facilities.

Access to Oil. As I said in Cooper, “Mineral Mastery” (Grantville Gazette 23), “The oil fields which can be developed by anyone are those of the Gulf Coast, parts of the Arabian Peninsula, and perhaps California and Nigeria. Access to the fields of Mexico, Venezuela, the Middle East, Galicia and Russia is likely to be restricted on the basis of nationality.” I would add that while Trinidad is under Spanish dominion, it would be relatively easy to seize it (we collected oil there, without much hindrance, in Cooper, “Stretching Out, Part 4: Beyond the Line,” Grantville Gazette 16). Also, Suriname is under USE control and there is some possibility of finding the oil at Tamburedjo.

The fact that an oil field is under Spanish, Ottoman or Persian control doesn’t mean that the oil won’t be developed, it just means that the USE will probably have to buy it from a local entrepreneur. And the fact that we are presently at war with Spain (and facing hostility from the Ottomans) doesn’t mean that they won’t be perfectly willing to sell oil to us; the Spanish and Dutch traded war materiel even when they were at war.

When the giant oilfields of the Middle East were opened up, the price of heavy heating oil in Hamburg fell, from 146DM/ton in 1957 to 88 in 1958 and 66 in 1959. Likewise, light heating oil dropped in price from 242 to 144. The result was that “within Germany, oil was absolutely cheaper than coal,” and homes and factories switched from coal to oil heating. (Milosch 85–6). So the cost advantage of coal over oil, even in Europe, is not eternal.

Military vulnerability. While I don’t doubt that there will be efforts to copy USE military innovations (steamships, ironclads, explosive shells, etc.), I think that the USE has the technological edge and the population base to keep that edge. (Given the rivalries among Spain, France, England, and between the Ottomans and the Hapsburgs, I doubt that any combination against the USE will be maintained for long.) Consequently, I think that we will be able to break blockades of our ports and also provide adequate convoy escort service for our tankers. Which are likely, in the 1640s, to be oil-fired steamships.

Transport Costs. With regard to the cost of transport, in the seventeenth century it was much cheaper to transport goods by water than by land. Cooper, “Hither and Yon” (Grantville Gazette 11). (This is nothing new; in Roman times, the cost of transporting wheat by sea was 1.3%/100 Roman miles, and by land, 55%. In the early eighteenth century, English land transport was still over 20 times as expensive as transatlantic shipment. Duncan-Jones 368). “In 1816, the cost of shipping a ton thirty miles overland in the United States was the same as shipping the same ton to England. The average cost was seventy cents per ton per mile (a ton-mile).” (Mabry)

Because oil has a higher energy content than coal, and the diesel engine is more efficient than the steam engine, the cost of fuel per unit power generated would be equal if the cost of oil was about three times the cost of coal. (Wells 85).

In 1915, the cost of oil was perhaps 18s6d–28s/ton in oil-producing countries, whereas in non-producing countries without substantial tariffs, it was 38s–59s/ton. In Germany, the duty was 32s/ton, resulting in a price of 62s–79s/ton. (Id.) (implying a duty-free price of 30–47). The estimated cost of coal was 14s/ton. (86).

Wells compares marine diesel with marine steam; with oil at 40s/ton (consumed 10 tons/day) and coal at 14s/ton (consumed 42 tons/day), and with engine-room staff being 16 for the coal-powered ship and 8 for the diesel, the cost per ton mile (counting fuel, wages, and provisions) was.0067d/ton-mile for coal and.0035d/ton-mile for diesel. (86ff).

It is interesting to note that in 1900, Germany imported 145 million gallons of crude and refined oil from the United States, and 32 million gallons from Russia, while producing 15 million gallons. Plainly, the Germans were willing (if not eager) to pay the piper to get petroleum, despite their huge coal fields.

Transport Capacity. With regard to transport capacity, in the seventeenth century, a large transatlantic trader would be 250–500 tons “burden” (originally a measure of what could be carried in wine barrels). Oil is roughly 7 barrels to the ton so such a trader could carry 1750–3500 barrels. A dedicated tanker with an oil compartment, I suspect, could carry perhaps one-third more, getting us up to the 5000 barrel range. If this were a light crude, like that of the Gulf Coast, it could be 50% gasoline (EPA/Appendix 6A), which would be 2500 barrels (~100,000 gallons)—enough for 133 days supply at the 750 gallon/day demand level.

Of course, if the overseas field produced a heavy crude, like that of Wietze, it would be prudent to refine it on the spot and only ship over the useful fractions.

Once steel production ramps up enough for steel steamship construction to be practical, we will see tankers with a carrying capacity of several thousand tons, which in turn will make it that much easier to supply oil.

In OTL, the “real” price of oil (in 2008 dollars) fluctuated erratically over the first decade of production, hitting a high of about $110/barrel and a low of under $40. From the late 1870s until the early 1970s, it remained under $40/barrel and indeed I would estimate the mean as about $20/barrel. Production isn’t likely to climb as quickly as it did in OTL (where most early development was in America), but, on the other hand, the population, and hence the demand for oil, will also be smaller.

Ports. After the Baltic War, USE territory includes the ports of Stettin, Stralsund, Rostock, Wismar, Lubeck and Kiel on the Baltic Sea, and Hamburg, Bremen and Emden on the North Sea. The allied Union of Kalmar has its own ports, including Stockholm and Copenhagen on the Baltic Sea and Aarhus, Malmo, Goteborg, Oslo (Christiania), and Bergen on the North Sea. In addition, there is river traffic down the Rhine to Rotterdam, and then by canal to Amsterdam.

These ports were visited by merchant ships of moderate size and therefore should be able to accommodate tankers of up to 100–200 tons burden, at least. By the time we have locomotive-grade diesel engines, say the 1650s, it’s quite likely that at least one of these ports will be improved by dredging so it can accommodate larger vessels. Remember, there are a lot of goods that the USE is going to be importing and exporting by sea so there are considerable economic advantages to having a deepwater port.


Motive Power

The motive power for the railroad has two basic elements, the power plant and the transmission.

The power plant (engine, prime mover) converts some other form of energy into a mechanical form—the rotary movement of a turbine or the reciprocating movement of a piston.

The transmission takes the kinetic energy of the turbine or piston and uses it, directly or indirectly, to turn the wheels. For a stationary power plant, transmission normally is electric, but we will briefly discuss pneumatic systems.

The first “locomotives” in the new time line were pickup trucks (with gasoline or diesel engines) hauling rail cars on strap rail tracks. There were also horse-drawn trains.

Steam locomotives appeared at least by 1634, possibly earlier. Steam locomotives have been discussed at length in Cooper, “Harnessing the Iron Horse: Railroad Locomotion in the 1632 Universe,” Grantville Gazette 7; Edelberger, supra; Evans, “Fire Breathing Hogs” (Grantville Gazette 20).

Eventually, the steam locomotive will face competition from Diesel (especially diesel-electric) and straight electric locomotives, and perhaps other kinds as well. The 1953 Encyclopedia Britannica “Locomotive” article devotes three pages to steam, three to “straight electric,” and three to diesel-electric locomotives.


Power Plant Distribution

We have several choices as to how to distribute the power plant. First, it can be mobile or stationary.

A mobile power plant usually burns fuel, converting chemical energy to heat energy, and using the expansion of heated gas to operate the turbine or piston.

If it is mobile, we can put it onto a locomotive that pulls or pushes the other cars of the train. Or we can put it on every car of the train, in which case there is no dedicated locomotive. This may be advantageous if a single high-powered prime mover has substantially higher initial costs, or operating costs, than the equivalent series of low-powered prime movers. Or to improve traction by taking advantage of the weight of all the cars rather than just the locomotive.

If traffic is so light that the locomotive is only pulling one car, you might do better to replace the train with a single “railcar” (“rail motorcar”): a self-propelled passenger, mail or express freight car which travels on the rails.

We can take the prime mover out of the train entirely and instead use a stationary power plant, transmitting the power to either a single locomotive (really a glorified “motor”) or to individual cars each equipped with its own motor. (The latter are often referred to, rather cryptically, as “multiple units”; they are designed so that they can still be controlled from one cab even though each one propels itself.)

Finally, we can equip the locomotive, or individual self-propelled cars, with a portable energy storage unit, that is charged up at a stationary power plant.

We still have the question of whether it’s better to have one or two large stationary power plants, or many small ones. The latter is most likely to be considered an option when an electric railway is running on direct current, because that can’t be transmitted efficiently over a long distance. Still, power plants tend to have economies of scale favoring bigger but fewer facilities.


Mobile Power Plant Types

The steam (piston) engine is an external combustion engine, that is, the fuel is burnt in one chamber (the firebox) and the combustion gases serve to heat a working fluid (water in the boiler) inside the engine so that the resulting steam moves the piston in another chamber (the cylinder). A steam turbine engine is similar except that the steam moves turbine blades instead of pistons.

In an internal combustion engine, the fuel is burnt to generate a combustion gas, and the combustion gas expands against the piston or turbine, in the same chamber. The combustion can be continuous or intermittent. The ignition of the fuel may be by means of a spark, as in an Otto (“gasoline”) engine, or by compression, as in a Diesel engine.



Mechanical transmissions. In the nineteenth century steam “rod” locomotive, a connecting rod mechanically transmitted the forces on the piston to the wheel. This transmission has the disadvantage that there is a one-to-one relationship (“direct drive”) between a piston stroke and a wheel rotation.

This relationship can be altered by interposing a gear, so the engine turns a gear and the gear turns the wheel. A geared locomotive (Shay, Climax, Heisler) uses reduction gearing so it can achieve higher tractive effort (pull) at low speed than would be possible with a rod locomotive having the same size driving wheels. Most geared locomotives are single-speed, but a few had the ability to switch from one gear to another, and thus to change the engine-wheel speed ratio, like a car or truck transmission.

Other transmissions. It is also possible to convert the mechanical energy into some other form of energy (electric, hydraulic, pneumatic) and then back again “at the wheel.” This allows for continuous variation of the ratio, and thus for greater versatility.

If a locomotive type has a “two-part” name, like “diesel-electric”, the first part identifies the power plant(e.g., diesel engine) and the second part the transmission (e.g., electric).


Pistons versus Turbines

Most locomotive engines, whatever their type, drive a piston. However, it is possible to re-engineer them so that the expansion of the compression gas or the steam turns the blades of a turbine instead.

The turbine’s advantages are that it has fewer moving parts (potentially reducing maintenance, and requires less mass and volume for a given power level.

Also, two cylinder piston engines produce various vibrations as a result of the incompletely balanced movements of the pistons, and these can lead to mechanical wear, an unpleasant ride, hammering of the track, etc. (The balancing problems are exacerbated if the engine is coupled to a mechanical transmission, as more mass is involved.) A turbine avoids the problems of balancing reciprocating masses.

Turbines can be driven by combustion gases or by steam. The first combustion gas turbine-mechanical locomotive appeared in 1933. Unfortunately, the turbine’s power and efficiency are very strongly dependent on the rotational speed; that is, it runs best only close to full “load.” That’s a problem if the turbine is driving the wheels directly (mechanical transmission), since locomotives need to accommodate a broad range of speeds. A turbine-mechanical locomotive doesn’t run downhill, idle, or creep along very well. A workaround is to have several turbine engines which can be brought on line as needed.

Another problem with a turbine-mechanical locomotive is that it needs an “extra” turbine dedicated to reversing, because a turbine can turn in only one direction.

The first combustion gas turbine-electric reached the market in 1941. Turbines produce a rotary motion of the shaft, and that’s exactly what generators need to convert mechanical energy into electrical energy. So the turbine-electric combination is a natural one. The turbine can be run near full speed and if the load is light, the excess energy perhaps can be fed into batteries or even into a resistance heater to keep the fuel warm. Still, it’s best to operate them close to full load as much as possible, i.e., on high-speed, long-distance runs.

Union Pacific was the principal proponent of the gas turbine-electrics, and it used Bunker C oil as fuel. However, after a while this fouled the turbine blades (presumably as a result of incomplete combustion) and thereby increased maintenance costs. (Wikipedia).

A steam turbine (MRT) works pretty much like a gas turbine, except it uses pressurized steam rather a combustion gas, and it usually burns coal rather than bunker fuel. The first steam turbine-mechanical locomotive (with four turbines) was built in 1907, and the first steam turbine-electric in 1910. The most successful was probably the LMS Turbomotive 6202 (1936–49).

The advantages and disadvantages are similar to those of the combustion gas turbine. However, there seems to have been a problem of reliability on steam turbine-electrics; coal dust or leaking boiler water got into the traction motors. The C&O introduced steam turbine-electrics with much fanfare in December 1947 and quietly sold them for scrap in 1950. (Shuster 299).

Steam turbines do work quite nicely in stationary power plants, however, provided that they are large enough (Stott 1172).



The piston motion of a steam engine may be used to rotate a DC current generator, rather than a wheel, and the generated electricity then transmitted to a motor.

If there were two pairs of pistons, you could fully balance the lateral forces without resort to wheel-mounted weights that would cause rail pounding.

The first steam-electric locomotive was the Heilmann (1893). It was used to haul a test train, and performed well, but the design didn’t catch on commercially.


Diesel “Compression Ignition” Internal Combustion Engines

In the old time line, the Diesel engine was invented in 1893, the first Diesel locomotive was put into operation in 1912, and “diesel electric” locomotives were first used in passenger service in the Thirties.

In the Diesel locomotive, a Diesel engine (a “compression ignition” internal combustion engine) is used to convert the chemical energy of fuel into mechanical energy. Air is compressed (more so than in a gasoline engine), fuel is injected and ignited by the heat of compression, and the combustion gases expand, driving a piston.

The diesel fuel, being liquid, can be stored in small tanks located in otherwise wasted spaces and still easily delivered to the engine when needed. The handling of wood or coal for a steam engine is much more cumbersome. Of course, an oil-fired steam engine would have the same fuel handling advantage.

Diesel engines are 3–4 times as thermally efficient as steam engines (Vauclain), and diesel fuel has a higher energy content. A given weight of diesel oil in a diesel engine might do eight times the work of an equal weight of coal in making steam for a steam engine, so if it were four times as expensive, fuel costs would be halved by diesel use. (Mike’s). Also, please remember that “alternative” fuels for diesel engines exist, as discussed in the “Fuel” section.

A steam locomotive might need a pound of water for every pound of coal; diesels require much less water. Dieselization reduced the B&O’s water bill by over 80%. (Holt)

Because it doesn’t need to stop for water, and fuel stops are less frequent (every 500 versus every 100 miles), diesels make better time, and “crew districts” (typically eight hours travel) are larger. That reduces labor costs. (Solomon 13, 15).

Maintenance-wise, steam locomotives were typically out-of-service half the time, diesels more like 5–10%. (Coifman; Solomon 14). However, steam locomotives had a longer service life; 20–30 years versus 14. (Solomon 17).

It is much easier to operate diesel-electrics locomotives in combination (“multiple units,” MU) to haul a single train than to coordinate the operation of multiple steam locomotives (Coifman). Hence, we can increase traction without increasing locomotive size. Big heavy locomotives require gentler curves and increase track maintenance costs.

The great disadvantage of the diesel was initial cost, typically 2–3 times that of a steamer. Diesel engines had many more parts and they had to be machined to higher tolerances (1/10,000th vs. 1/100th inch) (Solomon 17; Francis 67; Wikipedia/Diesel Locomotive).

Weight was also a problem for early diesel. The high compression ratios needed for ignition meant the engine had to be strong enough to contain the gases. Until the Thirties, when high strength/weight alloys became available, that meant using a thick, heavy, cast iron or steel block. The Winton W40 had a engine weight-power ratio of 200 pounds/hp (as opposed to 20 for the 1933 Winton 201A). (Solomon 41ff)

Naturally, that also meant that the vehicle weight-power ratio was undesirable, making it difficult to scale up to a locomotive suitable for mainline service. A Baldwin diesel-electric locomotive (1925) weighed 275 pounds per horsepower. A steam locomotive of the same period was more like 140 pounds/hp. (Vauclain 46).

Modern diesels are more compact, of course; the 1960s Napier Deltic has an engine weight-power ratio of 5.5. (Ransome-Wallis 33).

It is worth noting that quite a few locomotive diesels (including the Winton 201A and the Napier Deltic) were first marketed, or co-marketed, to the navy for submarine and fast attack boats. The four ironclads of the Baltic War use diesel engines scavenged from coal trucks (Flint and Weber, 1633, Chapter 4), and it is likely the NTL Navy will be encouraging diesel engine construction.

Turbocharging (using exhaust gas to drive a fan that pushes more air into the compression chamber) increases power 30–50% (railway-technical; Holt). Turbochargers appeared on locomotives in the 1920s.

How powerful a diesel engine do we need? The answer will affect how soon diesel locomotives can be put into service. You can calculate the frictional resistance of a train of a given weight using the formulae in Cooper, “Harnessing the Iron Horse” (Grantville Gazette 7). The engine provides the tractive effort (force) that overcomes that resistance, and the speed of the train will be that which makes the “TE” equal the resistance.

The exact relationship between TE and engine horsepower is dependent on the electrical characteristics of the generator and the motor. With modern diesel-electrics, TE in pounds at full throttle can be very loosely estimated as 308 times the horsepower available for the generator, divided by the vehicle speed (mph), for speeds above 10–20 mph. (Hay 100).

However, I am not sure how typical that would be of the first diesels built in the new time line. It may help to consider the characteristics of some of the first successful diesel-electrics (Ransome-Wallis 113ff; Solomon 53ff).

A switcher with just a 600 or 900hp Winton 201A did just fine in the Thirties. And two of the 900hp models powered the E1 series passenger locomotives. These were replaced with two, more reliable, 1000hp EMD 567 engines in the E6 (1938), providing a maximum tractive effort of 51,250 pounds.

The first successful diesel freight locomotive, the Electro-Motive FT (1939). This had a two or four unit engine, each unit providing 1350 hp. The four units together weighed 900,000 pounds, spread across 32 driving axles, and totaling 193 feet in length. The 5400hp version produced a starting tractive effort of 220,000 pounds, and carried 4800 gallons fuel, giving it a 500 mile radius of action. It hauled 3500 tons from Winston to Barstow.

There is endless dispute as to the relative power of diesel-electrics and contemporary steam locomotives. The Y6, usually considered the most powerful steam locomotive ever built, had a maximum tractive effort of around 166,000 pounds. (The locomotive weight was 611,500 pounds, and with the tender added, the pair totaled 961,500 pounds.)

The EMD F7 diesel unit (230,000 pounds, 1500 hp) had a maximum tractive effort of 56,000 pounds. So a string of four F7s would be expected to beat even a Y6. (EMD also had an SD7 in 1952—maximum tractive effort of 90,800 pounds. So two of these would beat a Y6.)

Steamheads might respond, “so that means that it takes four diesels to beat one steamer!” But that’s not the point. The design philosophy for diesel electrics (and straight electrics) is different. Instead of building one big steam loco that is overkill for most jobs, you build say a 1350 hp unit capable of single or multiple operation. Two give you 2700hp, four, 5400, eight 10,800, etc.

There were limits to how big any steam loco could be, and they didn’t play well together on a single train, so no matter how powerful steam loco the steamhead has in mind, the diesel proponent can add enough MUs to beat it. (If the control circuitry will support it . . . .)

And when you don’t need them to combine efforts, they (at least the ones with cabs) can work independently.

Moreover, even a single diesel unit on the track beats a steam locomotive, however powerful, sitting in the maintenance shop.


Diesel engines are used in large trucks, and undoubtedly there are some Diesel engines available for study in Grantville. There are also mechanics with experience in the maintenance and repair of such engines.

There will probably be resistance to using any coal truck diesel engines, previously used in APCs and the ironclad, as “mere” locomotive engines. But if they do become available, they are probably comparable to the 2750hp Detroit Diesel engine on a Liebherr T282 coal truck of 1998. At the other extreme, if a pickup truck had a diesel engine, it would be perhaps 250hp (like the 1994 Ford Power Stroke 7.3L).

There undoubtedly will be efforts to duplicate these exemplars post-RoF, but it remains to be seen how quickly they can be duplicated and whether the necessary precision will be exercised.

While it’s helpful that there is mechanic-level expertise with Diesel engines, the learning curve is still going to be much steeper than with steam engines (Grantville’s “steamheads” probably built, or helped build, steam engines for tractors or locomotives, and probably have collections of schematics for steam locomotives.)

It took post-independence India about twelve years to go from importing all the parts for a 6hp Lister engine (for water pumps) and just assembling it themselves, to a completely indigenous diesel engine. (Lovson).

The Wikipedia article on Diesel locomotives asserts that there were problems with the reliability of modern diesel-hydraulics “built using parts made locally to German patterns under license.” If this happens in the modern world, what can we expect to occur in the 1630s? Remember Torstensson’s reaction to the micrometer in 1632.

The diesel engines in Grantville may be something of a mixed blessing as models. Their designs may reflect the availability of alloys we don’t have.



In a diesel-mechanical (direct drive) locomotive, there is a mechanical transmission (gears and the like) similar to that on a truck. Most diesel-mechanical locomotives have been small, low speed switching locomotives. The diesel engine has a small range of useful engine speed (rpm). For a diesel-mechanical to have a high maximum wheel speed, it would need an enormous gear train (20–30 gears if it maxed at 110 mph. (HSW).



In a diesel-hydraulic locomotive, the engine exerts pressure upon a liquid (water, mineral oil, etc.), which in turn acts on a hydraulic motor, which turns the wheels. The fluid is virtually incompressible so the only loss of energy is the result of pipe friction. On the German V200.0, the engines interacted with the liquid through a torque converter.

The reported advantages of the diesel-hydraulic design included reduced locomotive weight, better adhesion to the rails, excellent braking, and avoiding the electrical failure problems experienced with electric transmissions. (Grant 118). Diesel-hydraulic locomotives were used in post-WWII Germany and Britain. However, American railroads weren’t impressed; the Southern Pacific bought 12 Krauss-Maffei locomotives and found that they required extra maintenance. (Luna 108). I have also seen reports that they didn’t “work well in heavy or express locomotive designs.” (Railway Technical).



In a diesel-pneumatic (the German V320, 1929), the engine drives a compressor, and compressed air acts on the motor. The compression makes them rather inefficient.



The most popular diesel locomotive nowadays, at least in the United States, is the diesel-electric. The diesel engine drives a generator, which transmits an electrical current to an electric motor, which turns the wheels. There is also a control system to protect the engine, the generator and the motor.

Since the wheels are turned by motors, rather than by piston action, the driving force is applied more constantly, leading to better adhesion to the track and reduced track wear.

Locomotives with electric transmission can also take advantage of dynamic braking at speeds above 10mph. The motors are made to act like generators (instead of the electric current causing the wheels to turn, the turning of the wheels creates an electric current) and the “generator” drains kinetic energy from the wheels. That way, brake shoes don’t have to be changed as frequently.

On a conventional diesel-electric, the current is fed into resistors, and dissipated as heat (“rheostatic braking”). In theory, a diesel-electric can be equipped with some sort of energy storage system (like the lead-acid batteries on the “Green Goat” yard locomotive, or flywheels, or compressed fluids) so that this energy isn’t wasted.

The first generators were dynamos, which produce direct current. Later, these were replaced with alternators, which produce alternating current, and are cheaper, easier to maintain, and more compact. Likewise, DC motors were replaced with AC ones, which can carry a higher thermal load. (Holt).

The “weak link” in the early diesel-electrics was the control system (Campbell). Originally, there were separate controls for the engine and the generator (Coifman), and it was difficult to balance these as the load changed as a result of stops, starts, curves and grades. The engine could stall and the electrical equipment could burn out (Duffy 225). It took Dr. Lemp about thirteen years (1910–1923) to come up, in stages, with a solution, in which the operator simply used a lever to control the supply of fuel to the engine and the exciter circuitry adjusted the generator (Lemp USP 1589182). Note that the timing implies that the Lemp control system would not be found in EB11.

And that’s not our only problem. We certainly understand the basic designs of generators and motors. The question is whether we can build them to the power needed for at least a railcar, and more preferably for a locomotive, without melting the insulation or running into weight or size problems.

A typical current load for a modern diesel-electric locomotive is 600–1500 amps. (Halberstadt 13, 71, 75, 85, 93). A 1600hp Alco diesel-electric (1951) used silicone insulation for windings with a current rating of 1085 amps. (NSWGR). A 1925 locomotive had an 800 kw generator running at 600–1100 volts, which implies 730–1330 amps. (Vauclain 48).

These problems aren’t theoretical: “Almost all failures on diesels are electrical. One damned little short kicks a breaker and the entire locomotive is shut down.” (Westing 382).

That suggests that having good insulation will be important. The most immediately available insulation would probably be oiled paper or (more durably) leather. Natural resins (pine?) and waxes are also possibilities. By 1634–35 we should be able to use imported rubber or gutta percha, albeit in limited quantities. Plastics will also begin to be available. For polymer (rubber and plastic) availability, and suitability for electrical applications, see Cooper, “Industrial Alchemy, Part 5: Polymers” (Grantville Gazette 29).

The motors also have an amperage limit; they burn out if they operate at too high a current for too long (Holt). This in turn limits the torque, and thus the tractive effort, that can be coaxed from them.

Still, with new gasoline IC engines being built, however slowly and laboriously, in the new time line, the railroad companies are going to be acutely aware that the handwriting is on the wall for steam locomotives. Historically, the new, relatively primitive diesels had to compete with steam locomotives that were the product of a century of development. This time, there’s a more level playing field.


Gasoline “Spark Ignition” Internal Combustion Engines

Gasoline “spark ignition” internal combustion engines may be used, in place of diesel engines, as the prime mover on locomotives or railcars.

There are, of course, a lot more gasoline engines than diesel engines available in Grantville. They are typically lighter, and cheaper to build or maintain than diesel engines, and have a better power-weight ratio.

While most radial engines use gasoline, they can be designed to take diesel fuel (e.g., Bristol Aeroplane Company’s Phoenix I, 380 hp, 1067 pounds, 1928). However, they still wouldn’t have the efficiency of a true diesel engine.

A “gasoline” engine doesn’t necessarily need gasoline to run. As previously noted, canon says that some engines have been converted to run on natural gas. Also, it’s possible to eke out the supply of gasoline by use of mixes such as M85, the methanol-gasoline mix used canonically by “The Monster.”

Gasoline is likely to be scarcer and more expensive than diesel fuel, and gasoline engines have less endurance under continuous use. They are also less energy efficient than diesel engines, especially at low power, and slower to start. However, they still produce four or five times as much power from the same weight of fuel as a steam engine (Mike’s), and they start faster, too.

Our ability to use gasoline is dependent on producing sufficient “light” oil; the Wietze field, at shallow pay depths, produces mostly “heavy” oil (conventional diesel fuel is heavier than gasoline).

We have the same choices of transmission systems as we did with diesel: mechanical, hydraulic, and electric. The first commercially successful gasoline IC-electric locomotive was built in 1913, and had two 175hp 550 rpm V8 engines (SDRM). But note that it weighed 57 tons; 652 pounds/hp. (Solomon 34).

Historically, the gasoline-electrics made their debut as motive power for rail cars, and helped pave the way for diesel-electrics. That could easily happen in the new time line, because we have so many gasoline engines in cars that are parked indefinitely. The 140–145hp Vulcan V6 was the standard engine for the extremely popular Ford Taurus from 1992 on, whereas 133 or 194hp engines were available for the Toyota Camry of the late 1990s. Presumably, two engines could be paired up for railcar use. (There were two-engine, two-transmission systems in some diesel-hydraulic locomotives.)

There are also pickup trucks with gasoline engines. The Ford F-150, F-250 and F-350 of the Nineties had half to full ton engines of 145–380hp, and could tow 1–4 tons. That assumes resistance typical of rubber tires on asphalt; towing a railcar, I would expect it to handle a load 5–10 times as great (Lay; HNC), if adhesion were sufficient.

Douglas Jones pointed out to me that pickup trucks are grossly overpowered; their chassis are too weak to carry the load that they need to get the traction that their engines are capable of providing. He suggested that the up-timers could build a new, more massive frame to receive the engine.

As for new builds, canon says that four 220 pound, 120hp 7-cylinder radials were delivered by Swartz Aviation, probably in early 1635. It appears that they took six months to make, primarily using handmade parts. Huff and Goodlett, “Spark of Inspiration” (Grantville Gazette 13). By 1636 we might see production on the order of three/month. Of course, the aircraft industry will be snapping those up.


Straight Electrics

The straight electric locomotive, like the diesel-electric, has an electric transmission, but its energy source is externally generated electrical energy.

The advantages (such as multiple unit operation) imparted by the electric transmissions of diesel-electrics also apply to straight electrics, but the latter has some additional advantages.

Straight electrics are capable of supporting rapid acceleration since the central power plant is much bigger than what could be put on any individual locomotive. That’s very desirable for urban rail service, where stations are close together.

Straight electric “locomotives” don’t have a power plant on board, and hence are simpler to construct, and have less down-time and lower maintenance costs than even a diesel-electric. (In theory this simplicity should also translate to lower locomotive purchase costs, but in OTL, diesels benefited from economies of scale.)

Electric locomotives are quiet and non-polluting (the power plant is another matter, but it’s less of a problem than the steam or diesel locomotives it replaces) which has made them attractive for use in cities.

Their efficiency is enhanced by a more versatile form of dynamic braking. In a straight electric system, the current is fed back into the power distribution system where other trains can use it (“regenerative braking”). Clearly, this is more energy efficient than rheostatic braking. Amtrak has said that regenerative braking reduces energy consumption by up to eight percent. (Amtrak). Regenerative braking is most advantageous when the volume of traffic is the same in both directions, on a steeply graded line.

Straight electric operation imposes high initial infrastructure costs (for the central power plant plus electrification of the entire line), except for the battery-type electrics. In addition, line maintenance costs are higher, because the overhead or third rail must be kept in working order.

The first electric locomotive was built in 1837, and was battery-powered. Obviously, reliance on batteries will limit the available power. The first third rail system went into operation in 1879. The first electrified lines were urban subways and suburban commuter lines. The first mainline electrification was in 1893; an overhead line was installed in Baltimore’s Howard Street tunnel, from which steam locomotives were banned. (SDRM)

As for mainline electrification, the infrastructure cost is proportional to the distance to be covered. The vast distances between cities in early twentieth-century America made it difficult for electrification to be considered cost-effective there.

The Chicago, Milwaukee, St. Paul and Pacific Railroad electrified two districts, a total of 656 miles. The cost of the second electrification (1917–27) was $257 million, and the railroad went bankrupt, in part as a result of the unrecovered electrification costs, in 1925. The other major American mainline electrification was that of the Pennsylvania Railroad, and totaled 2677 miles.

Electrification is widespread in modern Europe, but of course the population density in 2000 is much higher than it was in the seventeenth century and even with improved medical care and nutrition there are limits to how fast the population of Europe will grow.


Electricity Generation. This is by a stationary power plant. It can use a source of energy other than fuel (chemical energy), such as the gravitational potential energy of falling water (hydropower) or something more exotic (wind, tide, geothermal, solar, etc.) This article will not discuss the more exotic power sources.

In 1910–1920, the coal-powered reciprocating steam plant was usually more economical than a hydroelectric plant up to a “load factor” (demand/capacity ratio), of about 50%. Steam turbine plants were superior to reciprocating steam, but only in the larger plant sizes.

Early electric railroads built their own power plants, whereas later ones simply bought electricity from a power company. Naturally, if a railroad is buying electricity from a power company, the price will include a profit for the latter. If that profit margin is high, then the railroad will certainly be tempted to build its own power plant.

It can then power the railroad at cost, and sell excess electricity to other consumers to further defray its costs. The catch, of course, is that the savings have to be high enough to pay back, within a reasonable time, the cost of constructing the power plant. And it’s also helpful if the other customers need energy at different times than the railroad, flattening out the “load curve.”

Electricity Distribution. Third rail direct current (DC) systems are used on some suburban railroads. The principal alternative to third rail is the overhead line (“catenary”) system. This can carry DC, single phase alternating current (AC), or three phase AC. In 1996, the most common system were single phase AC at 25 kilovolts (kV)(36%), DC at 3000 volts or more (33%), and single phase AC at 15 kV (15%)(Oura).

Power is voltage times current. If voltage is low, then current must be high, and energy loss (as a result of the resistance of the wire) is proportional to the square of the current. So high voltages are desirable, but unfortunately, even in the early twentieth century, it was difficult to obtain a voltage high enough for long-distance power transmission with a direct current system. (Christie, 524).

Hence, practical implementation of DC railways involved transmitting high voltage AC power to rotary converter substations which then convert it to lower voltage DC for train use. Substations are 5–10 miles apart, to minimize transmission losses, but transmission efficiency is still lower than with the alternatives. DC tends to be used for short haul (metro or suburban) systems.

AC systems don’t provide quite as much traction as comparable DC systems. Nonetheless, by the Thirties, AC systems were preferred. At one time, electricity was distributed by AC, but then converted on the locomotive to DC to maximize traction. This required rectifiers suitable for locomotive use, which OTL didn’t appear until the Fifties. Later, AC motors were developed that had speed and torque control equal to the old DC models.

Some AC systems also use substations, but their purpose is to step down the voltage, and DC requires eight times as many substations.

In modern practice, the simplest form of overhead line is a single wire, usually steel or bronze (as on the TGV). These are strong but not especially good conductors, so an alternative is hard-drawn copper or, with a little more industrial finagling, copper-clad or aluminum-clad steel. It is also possible to hang one or two conductive contact wires from a strong messenger cable (catenary); the support wire is then preferably galvanized steel, and the contact wire may be copper, aluminum, or a copper-silver alloy. (Oura).

Three-phase AC uses three conductors each carrying an alternating current, but peaking at different times (phases). Several old texts indicated that three-phase power transmission required use of two contact wires rather than one, increasing construction costs.

The overhead line must be supported; in early practice, it was on wood or steel poles, or steel towers. Wood poles are cheap but must be closely spaced; steel towers are at the other extreme. In modern practice, aluminum, concrete and reinforced plastic supports have also been used.

The wires are bare, but are attached to the supports through porcelain or glass insulators, either above (suspension) or below (pin) the wire. The insulator has more than an electrical function; it must help bear the load.


Hybrid Electrics

Hybrid electrics are designed to use more than one power source. This could be, for example, two different voltages. Or both DC (overhead or third rail) and AC power. Or battery and overhead. Or diesel fuel and overhead (a diesel-electric that also has a pantograph so it can receive power from an overhead line).

Hybrids are used mostly when a locomotive is forced to travel over a line with both electrified and non-electrified, or differently electrified, divisions. They save the trouble of having to change locomotives at the boundary, at the expense of having a more complex, expensive locomotive.

The hybrid diesel-electric is most likely to be used on a line that has short electrified sections, e.g., for tunnels or steep grades. Note that it will have the regenerative braking advantage of a straight electric when going downhill.



Pneumatics. The motive systems described above differ in many respects, but in all cases, the immediate reason the train moves is that force is applied to its wheels so that they turn. However, that isn’t the only possibility.

In a pneumatic railway, a difference in air pressure to propel a train. Alas, their day will never dawn in the new time line, because everything they can do better than a steam locomotive, an electric locomotive can do better still. But that doesn’t mean that someone won’t try to make them work . . . .

The canister-driven pneumatic locomotive is the Aeolian equivalent of the electric battery locomotive. Instead of batteries, it carried compressed-air tanks. In essence, their advantage was that they did not require a fire or produce smoke. Likewise, they didn’t need to carry the weight of a firebox and a boiler. Unfortunately, they were inefficient because you lose some of the heat of compression once the compressed air cools. Also, if the air, after expansion, gets too cold, ice forms in places where you really don’t want it.

A compressed-air-driven vehicle was run, on a test track, in 1838. The first truly successful design was the Hodges engine, with a reheater between two piston stages. It found a niche in coal mines, especially gassy ones; hundreds were sold in 1896–1930. Chances are that the battery-driven locomotives will preempt this market, unless pressurization technology advances more quickly than storage battery technology.

The pneumatic equivalent of the electric third rail was proposed by Medhurst (~1812). In essence, a piston hung below each car. This piston rode inside a tube with a slit opening at the top. The slit was necessary, of course, to accommodate the strut connecting the piston to the car. The slit was sealed by some flexible element, such as a flap, to create a “valve.” Central pumping or fan stations evacuated the air in front of the piston, or compressed the air behind it, or both. The difference in air pressure created a force on the piston, and the piston carried the car along with it.

At least three piston-in-tube pneumatic railways were built in the early days of railroading, and operated for at least a short period of time: Dalkey (Dublin & Kingston) (1.5 miles; 1844–54); London & Croydon (initially 5 and later 7.5 miles; 1846–7); Paris & St.-Germain (1.4 miles, 1847–60); South Devon (initially 15 and later 20 miles; 1847–8). (Brader) There is a brief description of these systems in EB11/”Atmospheric Railway.”

On the South Devon line (where the use of pneumatic technology had been promoted by Brunel), there were eight pumping stations, three miles apart. The tube was 13 inches diameter so with the air evacuated enough to create a 10 psi pressure differential, the total driving force was 1344 pounds. With a light train, a speed of 70 mph was achieved (Mike’s).

Unfortunately, it took 865 horsepower to do the work that Brunel expected to be done by 300 horsepower, so operating costs were high (this was partially attributable to the lack of telegraph communications between the pumping stations. The valve began to fail in 1848, and the pumps were replaced with steam locomotives.

On the Dalkey, the tube was 15 inches diameter, it took five minutes to exhaust the tube enough to start the train, and the reduced pressure on the forward side of the piston was eight pounds (about half-atmospheric). The leather lasted for six to eight months before it had to be replaced. (Bramwell).

There were a variety of problems with these systems. The leather flaps (or its tallow coating) could be eaten by rats, or simply deteriorate as a result of freeze-thaw cycles. (MRT) In the new time line, we will be able to use rubber or plastic flaps, instead.

The third option is the tube-tunnel pneumatic railway; the entire car sits inside the pneumatic tube. The advantage is that since the rear is much larger in area, much less of a pressure difference is needed to generate the same force. The disadvantage is that the passengers are likely to feel that they are fitted inside cylindrical coffins. This system was used at the Crystal Palace line, which operated as essentially a tourist attraction in 1864. The propulsion system was a 22-foot diameter fan, and it only needed to generate a 0.02 atmosphere differential. The car was propelled at 25 mph.

There was never a general adoption of any pneumatic system for mainline railroad, so perhaps the proponents of pneumatic railways will just be whistling in the wind. (Groan.)

If pneumatic railways find a niche, it will be in subways and mines, where one can’t use a steam engine . . . and then only until straight electrics are available.


Sail cars. In 1830–31, the Baltimore and Ohio Railroad experimented with Evan Thomas’ “sail car,” the Aeolus. According to B&O’s General Counsel, it didn’t work well: “It required a good gale to drive it, and would run only when the wind was what sailors call abaft or on the quarter. Headwinds were fatal to it, and Mr. Thomas was reluctant to trust a strong side wind lest the Meteor might upset . . . .” (Stover, 35). It received a positive spin from a Baltimore historian; “when the wind was favorable its performances were highly satisfactory,” impressing a Russian diplomat who took a ride on it. (Scharf 321).

What was new about the B&O sail car was that it was mounted on rails; the Chinese reportedly built a sail wagon around 500 A.D. (Burgan 6).

While the B&O pronounced it a failure, I found that a sail car proved useful on an industrial track, running three-quarters of a mile from a dock to an ice house, in St. Petersburg, Florida (where apparently it is often windy). For a photo, see Popular Mechanics, July 1911, page 26.

Railplanes. Finally, consider the Bennie Railplane, which hung from a monorail and had front- and rear-mounted propellers. (Mike’s). Because it was driven by the lift provided by the propeller, rather than by driving wheels, it didn’t need to be heavy to “adhere” to the rail. You can watch a silent film showing it in action on an eighty foot test track. (Scottish Screen Archive).


Cost-Benefit Analysis of Electrification and Dieselification

Electric versus Diesel

Electrification requires a huge initial investment in the overhead line and related structures, coupled with a more moderate initial investment in the electric locomotives. The payback comes in the form of lowered operating costs. Typically, electric locomotives have lower maintenance and energy costs. The locomotives themselves are usually more expensive than diesels, but this is balanced out by the fact that you need fewer electrics to do the same amount of work.

The most obvious energy source for an electric power plant in Germany is coal. Bituminous coal has an energy density of 24 MJ/kg (Wikipedia), and if the plant burns it with a conversion efficiency of 40% (range is more like 30–50%; (Roth 2), or 32–34% (McNerney 4), that yields 2.7 kilowatt-hours/kilogram. Of this, perhaps 76% reaches the rail (Steimel 10); that’s a net of 30%, or 2.0 kwh/kg. It will be better if the plant burns anthracite (32.5 MJ/kg) and worse with lignite (14 MJ/kg). (There are parts of Germany in which lignite or even peat would be the most likely fuel.)

Diesel fuel (density 0.85 kg/liter) has an energy density of 46.2 MJ/kg (Wikipedia)—almost twice that of coal—and the combined efficiency of the diesel engine and its electric transmission is about 30% (Schobert 275; cp. Steimel 10 for diesel-hydraulics), yielding 3.85 kwh/kg (or 4.53 kwh/liter) at the rail.

So that means that for there to be any energy savings as a result of using electrics, the cost/kg of diesel fuel must be at least 93% more than the cost of coal.

In the 1650s, the relative efficiencies may also work against coal. The earliest coal plants had efficiencies of under 3% (McNerney 4). Even in 1908, powerplants had efficiencies of only 3–11% (Hobart 25ff), and transmission losses were higher, too. Whereas even in 1913, there were marine diesel engines with efficiencies of 32–35%. (BSB). So, it’s possible that there will be a period in which the diesel engine is more efficient than the available coal-powered powerplants. So that would require that the price of diesel be even higher to make coal competitive.

What about hydroelectric power? After all, “white coal” is free. Certainly, the operating costs of a hydroelectric plant are low. In 1909, Stott (284) said that they averaged 6% that of a reciprocating steam plant. In 1916, Stillwell said to allow $1/kilowatt for the operation of the hydroelectric plant. For a steam plant of 50,000 kw capacity, he suggested an operating cost, excluding the coal, of $3.50/kilowatt. With coal at $1–5/ton, and the plant running at 50% load, 200,000 tons of coal were needed annually, at a cost of $4–20/kilowatt.

The problem is, the plant must also be paid for. In 1916, “first cost” for a steam plant was $56–75/kilowatt capacity (Stott 1172). Stillwell assumed that his steam plant could be built for $63.70/kilowatt. Allowing 12% for interest and depreciation, that meant annual capital charges of $7.64/kilowatt.

In 1916, the first cost for a hydroelectric plant was at least $150/kilowatt, and, if a large dam was needed, $200–250/kilowatt was more likely (Stott 1172). (Mead 681 reports even higher numbers.) Interest and depreciation on the first cost would run perhaps 11–12% annually. Assuming 12%, that’s $18–30/kilowatt capital charges. That brings the annual hydroelectric cost to $19–31/kilowatt, versus $7.50–23.50/kilowatt for the steam plant. Stillwell concluded that if coal were at $3/ton and the capital charge was 12%, the maximum justifiable price for hydroelectric power was $147/kilowatt.

Perhaps because of cheap oil, for Class I railroads in the United States in 1944, 1949, 1954 and 1959, the fuel cost for diesel-electrics was substantially less, on a gross ton-mile (freight) or passenger train car-mile (passenger) basis, than for straight electrics. (NRC, Table 15).

Critical Traffic Density. Even under favorable conditions, the traffic density must be high for the operating cost savings to accumulate quickly enough to justify the up-front cost of electrification. We need to quantify just how high.

Passenger traffic is measured in annual passenger-miles (kilometers), and freight traffic in ton-miles (kilometers) (net tons are just the freight, gross tons include the rail cars and may also include the locomotive weight). There is no good consensus on how to combine passenger and freight traffic into a single traffic measure. Traffic density is the annual traffic per route-mile (kilometer) or track-mile (kilometer) of line; a double tracked line would have two track miles for every route-mile.

Analyses of the merits of electrifying a railroad that is already running diesel locomotives naturally were uncommon prior to the big run-up of world oil prices. I have found quite helpful a cost-benefit analysis set forth in a 1985 World Bank paper (Alston); it was detailed enough so that I could build a spreadsheet to implement it. It assumed that investment and maintenance costs of the fixed installations were proportional to track length, investment in locomotives and energy consumption proportional to traffic (measured in gross ton-kilometers), and locomotive maintenance proportional to locomotive mileage (measured in locomotive-kilometers).

Alston’s model provides several important insights:

—for a given combination of economic (discount rate, prices) and technological parameters, there is a critical traffic density (gross ton kilometers moved, per kilometer of track, per year) at which the net present value for electric vs. diesel operation is zero: if traffic density is higher, electric operation is more economical.

—the critical traffic density is proportional to the electrification infrastructure (overhead line, but not the locomotives) cost per kilometer if all other parameters are held constant.

—the critical traffic density is unaffected by a general price movement, i.e., all prices (electrification, maintenance, diesel fuel, electricity) altered by the same percentage. (So we don’t have to worry about converting from 1985 dollars to a different general price level)

—the critical traffic density is reduced if the ratio of the nominal annual operating cost savings to the initial up-front electrification infrastructure costs are reduced, e.g., by increasing the ratio of diesel fuel price/liter to electricity price/kilowatt-hour or overhead line construction/kilometer.

In Alston’s “base case,” the critical traffic density was 13,700,000 gross ton-kilometers/track-kilometer (per year), but Alston assumed that there would be a decrease in the rate of growth of diesel fuel prices mid-project that didn’t make sense in a 163x context. So my calculation yields a slightly lower critical traffic density (13,025,610).

I have tested Alston’s conclusions both by constructing a spreadsheet to duplicate his reasoning, and also by comparing his technological and economic assumptions (and traffic density conclusions) with other sources.

However, I want to comment on Alston’s energy costs. Based on his price and consumption assumptions (which were reasonable for 1985), on a gross ton-kilometer basis, electric operation cost 74% as much as diesel. But I saw that diesel consumption rates had been twice as high in 1960.

I did a certain amount of “sensitivity testing” of Alston’s model. For example, if I double the cost of diesel fuel, double the diesel consumption rate, and drop the “in-service” percentage of diesel locomotives from 86% to 65%, the critical density is reduced to 2,410,718. You could bring it down to 1,375,718 if you also reduced the discount rate to 6%. Or if you could halve the electrification infrastructure cost. Further reductions would require more pronounced pro-electric changes in the underlying parameters. And of course, we may find that some parameters should be moved in the other direction, e.g., an increase in the cost of electricity or in its consumption rate. In view of these findings, I think it would be unlikely that the circumstances will result in a critical traffic density less than 1,000,000.

In 1915, the US average traffic density was 1,116,000 ton-miles/route-mi freight and 114,000 passenger-miles/route-mi. However, for twenty of the more important railroads, the freight density ranged from 522,000 to 7,220,000, and the passenger density from 49,600 to 738,000. (Williams 78). So one can imagine that when the nationwide traffic density is only 100,000, there could be individual railroads with a density of 1,000,000. And when the nationwide is a million, there could be individual ones at ten million.

So, what sort of traffic density might we have in 1635 and how long would it take to reach the hundred thousand, million, and ten million levels?

Initial Traffic Density on USE Railroads. In 1820, the English turnpike roads had a traffic density of 2,383 ton-miles/mile. Germany in 163x doesn’t have a road system anywhere near as good as that turnpike system. But let’s assume, as a starting point, that once a railroad is built, that it will generate a traffic density that bears the same relation to the population of 1600 Germany that the English turnpike system did to the population of 1820 England. If so, then we would predict an initial freight traffic density in say 1633–35 of around 1,600 ton-miles/mile.

It has been estimated that Germany circa 1800 transported 325,000,000 ton-miles/year by horse (Pomeranz 301). I don’t know the total road distance then, but in the late nineteenth century it was 265,000 miles. (Mulhall, Dictionary of Statistics 516). Since there was probably less roadway in 1800, that implies that road traffic density was at least 1226. We would capture the long-distance portion of that business for which the origin and destination are close to a railroad station, and also generate some new business because of the lower cost/ton-mile of rail transport.

In 1839, when there were only about 2700 track miles in the USA, the freight traffic density was 11,115 (net? ton-miles/route mile), and the passenger figure was 33,346. Now, the population density in the USA 1839 was lower than in Germany 1600, but it’s difficult to decide whether that’s good or bad. With a lower population density, less passenger and freight traffic might be generated, but on the other hand, they probably need to travel farther to reach the destination, so the number of ton-miles may remain the same.

So a fair estimate for the 1635 rail traffic density level would be 1,000–10,000.

Traffic Density Growth Rate. There is general agreement among scholars that traffic density is positively influenced by growth in both population and economic productivity. However, I have done a series of regression analyses on both US data from 1939–1910, and cross-country data from 1912, and there is no formula that closely fits that data. And published regression analyses, based on other samples, disagree with my results and each other. And, to be frank, it’s not that easy to predict the USE’s population or economic growth, anyway. Nor can we easily forecast the price of railroad transport relative to competing roads, although it’s reasonable to assume that it will be cheaper.

What we can do is say how many years, at a particular growth rate in traffic density would be needed to reach the levels I mentioned.

Traffic Density Annual Growth Rate




Years to increase 10-fold




Target Traffic Density

Year in which target density is reached with indicated growth rate if initial traffic density is 10,000 in 1635













Looking at the increase in combined traffic density in the USA from 1839 to 1910, the geometric average rate was 13.9% for 1839–1849, and thereafter varied from 1.5–8.4%. For 1839–1910, it averaged 5%. (Using Alston’s conversion to gross ton miles, the USA passed the 100,000 mark between 1839 and 1849, and the 1,000,000 mark (per route mile) between 1890 and 1900. )

Now, I realize that we are going to have a massive dissemination of up-time knowledge. Still, it will take time to seriously impact the size of the labor force or its productivity.

China experienced rapid economic growth in 1978–2003 (GDP per capita from $240 to $4020 in 2003USD), as it attempted to modernize after cutting itself off from most of the world. Over 1978–2000, passenger traffic multiplied more than four fold and freight traffic two fold, while the rail network increased 20%. (Bouf) Combining the two forms of traffic, this impressive increase still amounts to an average annual increase of 9.3%. This leads me to believe that the USE will be hard-pressed to maintain a traffic density annual growth rate greater than 10% over a period of decades.

Electric v. Steam

Murray, the consulting engineer for the New Haven (which electrified in 1907), confirmed that “success is entirely dependent upon density of traffic.” In 1911, Burch (500) declared, “Railroads must have 10 trains each way per day or haul 1,000,000 ton miles daily, per 100-mile division [equivalent to traffic density of 3,650,000 ton-miles/route-mile], before electrification is practical . . . . Electrification for passenger service alone, from the terminal of a city of less than 300,000 people, is financially impractical.”

As a quick-and-dirty estimate, in my Alston model spreadsheet, I changed the diesel availability from 0.86 to 0.50, and tripled the fuel consumption per gross-ton kilometer, to simulate steam. The critical traffic density dropped from 13,025,610 to 3,043,158. That fails to take into account the savings in labor costs, or any differences in pulling power or speed between steam and diesel.

Thus, it appears that electrification of a steam railroad is worthwhile if it has reached a critical traffic density that is about one-third what the critical density would be if we were contemplating electrification of a diesel system, and, of course, if dieselification is not then an option.

Diesel v. Steam

This is the easiest sell of all. The operating cost advantage of diesel over steam is nearly as great for electric over steam, but the up-front costs are much smaller—simply the purchase cost for the diesel locomotives. In 1936, the diesel:steam locomotive cost ratio was 2.5:1 (Coloroto). In 1940, you could get 4–5,000 horsepower at the rail by investing $175,000 in a steam locomotive or close to $500,000 in a diesel-electric (Grant). In 1946, if a steam locomotive cost $85,000, the diesel-electric would cost $200,000. (Francis).

In 1944, in the United States, the fuel cost per 1000 gross-ton miles was 22.9 cents for steam and 11.0 cents for diesel. Or 2.71 cents per passenger-train car mile for steam and 1.48 for diesel. Prices were higher in 1949, 1954, and 1959, but diesel maintained a substantial energy cost advantage over steam. (NRC Table 15).

In 1957, the unit cost of fuel in the United States was $6.29/ton for coal and $2.91/barrel (*6.7barrels/ton=$19.50/ton) for fuel oil. Nonetheless, it was estimated that if the existing diesel locomotives were replaced by an equivalent number of steam locomotives (mostly burning coal), fuel cost would have been increased by 112%. Additionally, repair costs would have increased by 98.7%. (Table 14).


There was quite a bit of disagreement on the Bar as to how soon we would be able to build diesel engines. Estimates ranged from 1635 to 1680.

The way I see it, transferring diesel engines from the coal trucks (used as APCs, the core of the USE strike force) to ironclads is a case of robbing Peter to pay Paul. There is going to be tremendous pressure from the military to build at least crude diesel engines so as to alleviate the shortage.

While canon says that new internal combustion radial engines have been made in the 1632verse by early 1635, diesel engines are likely to be more difficult to manufacture. It’s a WAG, but I would say that it will be the 1640s before we have new diesel engines for capital ship use, and the 1650s before we achieve the power-weight ratios needed for a locomotive (or fast attack craft).

Likewise, there are myriad reasons why we will want to develop flexible insulation suitable for high amperage applications, and that is the principal bottleneck for developing locomotives with electric transmissions. I address the insulation issue in my polymers article and the bottom line is that it’s plausible that in the late 1630s and early 1640s progressively more suitable polymers will appear.

That will be, most likely, before we can make our own diesel engines. If there are up-time diesel engines which are powerful enough for a locomotive but not enough for an ironclad, and we don’t need them for an APC, then perhaps we will build an experimental diesel-electric. Obviously we will have enough fuel for a single experimental engine, and until we can actually make our own diesels, we aren’t going to be contemplating “dieselification” of the railroad system.

While it is undeniable that in the old time line, diesel displaced steam, steam still has its proponents. They point to the enormous disparity, at the end of the twentieth century, between coal and oil prices (over seven-fold in 2007) and urge that with modern technology, the thermal efficiency of the steam locomotive can be improved, from the old 6% to perhaps 27%. As for maintenance costs, they urge that there were a few late model steam locomotives (N&W Class J) that were cheaper to maintain than the contemporary diesels. (Rhodes).

These advanced steam locomotives feature triple expansion engines, a gas producer combustion system, multi-stage feed water and combustion air heating, the Lempor exhaust, Porta boiler water treatment to inhibit scaling, automated boiler and traction control, “water brakes” for dynamic braking, and other improvements. The hard question is whether, even with the headstart given to steam locomotion by the “steamhead” hobbyists in Grantville, and its machine shops, we will conceive of, and build, these high-tech steamers soon enough to stave off dieselification. And whether we will see the same oil/coal price disparity at the critical point in the railroad history of the new timeline.

If there is no suitable diesel engine in the 1640s, there are a few alternatives. First, we might have some sort of gasoline-electric locomotive. We already have the gasoline engines, and we can make more. So it’s pretty much a matter of whether we can obtain fuel (gasoline or a substitute) at a reasonable price.

The window of opportunity for gasoline-electric locomotion is short; essentially, gasoline-electrics have a chance if (1) gasoline (or an alternative fuel) is available, (2) the problems of “railroad-scale” electrical equipment are solved while the engineers are still tinkering with the equivalent Diesels, and (3) traffic hasn’t reached the level at which straight electrics are cost-effective.

Secondly, we could introduce steam-electrics. We will be able to produce steam engines in quantity before gasoline engines, but the question is whether we can solve the maintenance problems that were experienced OTL.

Finally, we can produce a straight electric locomotive. I must emphasize that there is no way that mainline electrification is going to be cost-effective in the 1640s. What I am talking about is either an urban commuter line, or more likely a very short experimental line that probably doubles as a tourist attraction.

Come the 1650s, and we should be making locomotive-grade diesel engines. I expect that we will have ready access to overseas oil by then. I also expect that we will not yet be able to justify the infrastructure cost for mainline electrification.

Electrification will come first in urban/suburban light rail. But to economically justify commuter service electrification, we need a large population living in a relatively small area. Magdeburg (20,000 before the sack) doesn’t qualify. Paris (~400,000) and London (~300,000) are possibilities.

The first mainline electrification will be in urban areas, long tunnels, or in mountainous regions.

As of 2005, the most electrified European countries were Switzerland (100% track electrified) and Luxembourg (95%), both heavily mountainous. Sweden was 77%; the Netherlands, 73%; Italy, 69%; Norway and Austria, 62%, Poland, 61%; Germany, 57%; Spain, 56%, France, 50%, Finland, 46%; Great Britain, 33%; and Denmark, 28%. (Wikipedia REA2005).

The flip side is that in OTL 2005, Germany was still running diesel-electrics over 40% of its track. Hence, I cannot agree with those barflies who were of the opinion that there would not only be early electrification in the USE, but that such early electrification would result in there never being dieselification.



In Richard Stilgoe’s song, “Light at the End of the Tunnel,” in the musical Starlight Express, we are told

Diesel is for unbelievers, electricity is wrong,

steam has got the power that will pull us along.

Steam won’t be pulling us along indefinitely, but unless Eric decides to skip the story line ahead a generation or two, we aren’t likely to see it replaced by diesel or electric.


Author’s Note

I regret to report that because of a boot hard drive crash, certain material that I had intended to provide with this article has vanished into the electronic abyss. These include my “Alston model spreadsheet,” my critical analysis of Alston’s assumptions, my cross-country and cross-time traffic density regressions, much of my bibliography, and very detailed nineteenth- and twentieth-century infrastructure cost, operating cost, and performance data for steam, diesel and electric systems. My (mostly reconstructed) bibliography is quite long and hence will be made available at “Gazette Extras”: