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Roxxy
2013-08-20, 11:40 PM
Shiyara the High Mediator

For my setting, I'm supposing a technology level between the sixties and the modern day (technology hasn't advanced at the same rate in the same areas as IRL). One thing I'm highly considering is problems in the focused on region's oil supply. At an America style consumption rate, they estimate running out within a couple decades. So, in an attempt to conserve oil, the government wants to MASSIVELY expand the nation's railroad system and institute heavy use of light rails, trolleys, subways, and monorails within cities and urbanized areas. Furthermore, while the city systems can run on nuclear generated electricity, the bigger trains replacing most intercity car and truck traffic need something more substantial. I'm thinking a return to steam locomotives just might fit that bill. True, there are good reasons diesels took over, but when you don't have a lot of oil, you can't be picky. With most intercity traffic relying on steam power, oil could be used just for the applications where there is no substitute, like aircraft and military armored vehicles. Renewable energy research is in the works, but is decades behind the modern day, so it won't be ready for a long time.

Now, this brings some questions. First off, I'm pretty sure we could build features into a steam engine that they didn't use back in the height of the steam era, but I don't know exactly what those features are, and what they would do. Fewer boiler explosions? More efficient coal burning? Less smoke? Better acceleration? With updated engineering, what is the performance difference likely to be compared to a diesel? I know this will be different than grabbing a steam engine from 1920 from a museum and putting it on the track, but not how.

Bulhakov
2013-08-21, 01:38 AM
A good list of modern steam advancements:

http://en.wikipedia.org/wiki/Advanced_steam_technology

Sith_Happens
2013-08-21, 01:47 AM
You know electric trains are already a thing, right?

Roxxy
2013-08-21, 02:09 AM
You know electric trains are already a thing, right?Steam has the advantage in cost, and with urban systems already relying on electricity, money has to be saved somewhere.

Ashtagon
2013-08-21, 02:41 AM
Nuclear powered supertrains the size of aircraft carriers.

Sith_Happens
2013-08-21, 02:46 AM
Steam has the advantage in cost, and with urban systems already relying on electricity, money has to be saved somewhere.

A power plant burning coal is many, many times more cost-efficient than an engine doing the same, even after transmission losses.

Roxxy
2013-08-21, 02:55 AM
Well, that pretty much ruins my excuse to use steam.

Sith_Happens
2013-08-21, 02:57 AM
Darn, now I feel bad.:smallredface:

Roxxy
2013-08-21, 03:12 AM
Damn it, this is fantasy. I need to start blaming wizards for stuff if I want to get anything cool. Let's use wizardry to make the coal burn hotter and cleaner, and let's also make the spells extremely short duration. Now, in order to get max efficiency, coal needs to burn "in house", as it were, as the stuff is going to be enchanted on site right before use.

Mutazoia
2013-08-21, 10:07 AM
Mono-tube boilers. When they fail, they don't explode, they just dump their water on the ground. While you could build a limited slip differential into a steam car your main problem to over come is fuel. Just like an infernal combustion engine, steam engines need to carry a fuel source with them.

With an infernal combustion engine the fuel is sprayed into the engine cylinder chamber and ignited by a small spark. The expanding gas drives the cylinder down.

With a steam engine power must be applied to the boiler to super-heat the water to evaporation temperatures where it is funneled through a series of chambers pushing the cylinder's down in succession by air (steam) pressure.

The main problem with steam engines is that, even with a smaller safer mono-tube boiler, steam is still horribly inefficient. It takes more energy to heat the boiler than it does to ignite gasoline vapor. And at the rate of consumption the steam engine uses more fuel to drive a car 10 miles than an infernal combustion engine would. The saving grace of steam engines is that, technically, water is free.

However...you may want to check out this article (http://empirehydrogen.com/hist-garrett.html) for a possible solution..

Joe the Rat
2013-08-21, 10:34 AM
With the exception of batteries powered by radioisotope decay, all nuclear plants and engines are steam turbines. Since your technology is between 60's-to-present, rather than assuming slower advancement, go with divergent advancement. A lot more effort was put into atomic power, and making it smaller and more efficient. Screw diesel. Your medium-heavy rail is powered by atomic steam turbine/electric hybrids, spitting the occasional jet of glowing blue steam.

As a consequence of the higher levels of ionizing radiation in industrialized areas, microcircuit technologies tend to be more unstable, favoring slightly clunkier but more resilient tubes and armored transistors.

Just throwing that out there.

Bonus points if you change your power source enough that your 'atomic' energy spits ambient magic as a by-product.

banthesun
2013-08-21, 11:04 AM
With the exception of batteries powered by radioisotope decay, all nuclear plants and engines are steam turbines. Since your technology is between 60's-to-present, rather than assuming slower advancement, go with divergent advancement. A lot more effort was put into atomic power, and making it smaller and more efficient. Screw diesel. Your medium-heavy rail is powered by atomic steam turbine/electric hybrids, spitting the occasional jet of glowing blue steam.

Not to mention all the steam thrown out by cooling processes! You could easily make nuclear trains that look and operate similar to traditional steam trains (minus the open furnace, hopefully). As a bonus, it makes train hijackings an even more dramatic event!

JusticeZero
2013-08-21, 01:59 PM
Since it matters for this, a quick primer on why we drive gas cars around.

Once upon a time, everyone used horses. Cleaning horse manure and dead horses off the street every day was a serious public works problem.

Then someone invented rails. The first ones were clunky, but then someone worked out how to bury the tracks flush with the road. The first streetcars were pulled by horses, and made travel much more democratic.

Someone decided that steam engines would work better. For long trips, they used coal powered steam trains and steamboats; for in town trips they invented cable cars, which ran a cable under the ground pulled by a central steam engine. The cars had a hook that reached through the slot in the ground and locked onto the moving cable as needed. These cable cars were inefficient, but nobody wanted steam engines in town, which is why they were so restrictive about the few steam cars of the time; it wasn't horribly uncommon for a steam engine to accidentally explode, with force similar to a modern day cluster bomb dropped from a bomber or worse.

Over time, steam engine technology would improve, but the old dangerous engines were still in circulation and exploding.

Someone devised the "trolly" to power a train by overhead wires; this is far more efficient than individual engines, since the economies of scale are handled at the power plant. Business tycoons would buy up all the land in a strip out in the middle of nowhere, put an amusement park at the end, then sell houses all the way down the line, all served with electricity coming off the trolly line. Suburbia! Within the space of only a few years, the streetcar networks of most every city in the world had exploded to fill the city.

Dunlop invented a pneumatic tire. This created a new development; comfortable and practical bicycles. Bicycles were the biggest thing to advance feminism ever, and very popular; furthermore, bicycles are cute and harmless. Instead of using laws to bar them from the city as steam cars, people instead started paving the roads to make it easier to ride bicycles on them.

Then, using all the advancements that had made steam engines safe - though nobody believed them - they created the gas burning engines. Car manufacturers argued that their vehicles were safe, and should be regulated as bicycles. This was accepted.

The president of the US visited Germany to see how Adolph had turned their economy around, and was taken by the government-owned freeway system. Returning, he built one in America, andother counbtries followed suit.

Then came WWII. Metals became rare and were needed for the war.

If you build a lot of a thing at once, they will all wear out at once. The streetcars were wearing out when the war started, and they couldn't get any repairs. They started to get more and more rickety, running on duct tape like fixes.

When soldiers returned, they wanted houses. The government set up a system to sell houses, but each house had to be on a big patch of land, and if it was in an existing neighborhood, they wouldn't pay or let people take out loans. Because rails were privately owned, they didn't get a chance to be included; because streets were paid for by subsidy, they were.

Then it came time that the streetcar companies could finally ask to get their rails repaired. To do this, they had to have bonds voted on by all of the cities, most of which had no streetcars. And the streetcars were rickety, not like the new roads. So the funding was denied and they ripped out the track to put in buses.

And by the way, you will note that there is now a big controversy about bridges falling down because they are old. Deja vu much? :)

The point of this is that people drive gas powered cars around because of a long string of arbitrary and happenstance reasons. A few changes in timing and we could have had steam cars, no cars, streetcars, or whatever. Long range trains currently use diesel engines; they could use a newer steam engine, but that's not what we decided to do. Inside of cities though, we use electric streetcars where we use rail at all.

The roads can have cars or steamcars or bicycles and streetcars, and they would all be justifiable. That said, modern safe steam engines do not inherently make things look steampunk - they don't have big boilers or anything like that.

A setting using streetcars would probably have smaller houses, no "suburbia", and a lot less racism - the post-WWII housing policies had a lot of racism written into them, which created long lasting, massive demographic issues that have serious effects long after the policies and attitudes that created them are lifted.

Roxxy
2013-08-21, 09:18 PM
I am completely for the atomic steam train idea. It melds the awesomeness of steam engines with a higher level of technology nicely.

Roxxy
2013-08-21, 09:27 PM
The point of this is that people drive gas powered cars around because of a long string of arbitrary and happenstance reasons. A few changes in timing and we could have had steam cars, no cars, streetcars, or whatever. Long range trains currently use diesel engines; they could use a newer steam engine, but that's not what we decided to do. Inside of cities though, we use electric streetcars where we use rail at all.

The roads can have cars or steamcars or bicycles and streetcars, and they would all be justifiable. That said, modern safe steam engines do not inherently make things look steampunk - they don't have big boilers or anything like that.

A setting using streetcars would probably have smaller houses, no "suburbia", and a lot less racism - the post-WWII housing policies had a lot of racism written into them, which created long lasting, massive demographic issues that have serious effects long after the policies and attitudes that created them are lifted.Thank you for that very in depth analysis. Let's say I go with the atomic train mentioned above and choose not to invest in the personal automobile (maybe the first attempts were poor enough that the idea was abandoned?). I'm still going to go with electrics for urban areas. Assuming I make this the historical choice instead of a reaction to loss of oil supplies, your last paragraph becomes the most important thing to the setting do to the implications of people not having access to an automobile.

Thanks for everyone's advice on this. I have sort of a thing for public transportation systems, and I wanted a setting heavily reliant on them. Since that determines how the economy is structured and how the PCs can get somewhere, this is a pretty important topic.

Ashtagon
2013-08-21, 11:04 PM
A little over a 100 years ago, someone submitted a patent for a special kind of steam train.

A tube would be built from London to Edinburgh, sealed, and filled with hit steam. As the steam cooled, it would contract, creating a vacuum. A special carriage would be allowed to enter the tube. This carriage would be mostly a single giant magnet, which would be used to drag a passenger carriage above the vacuum tube. The patent boasted a top speed of 5000 mph.

It's all quite improbable, and beyiond the engineering of the time (if possile at all). But it seems to match the tech levels you are going for.

JusticeZero
2013-08-22, 01:37 AM
I have sort of a thing for public transportation systems, and I wanted a setting heavily reliant on them. Since that determines how the economy is structured and how the PCs can get somewhere, this is a pretty important topic.
Sure. If you have any other questions, let me know.

OOPWER
2013-08-23, 08:26 PM
A little over a 100 years ago, someone submitted a patent for a special kind of steam train.

A tube would be built from London to Edinburgh, sealed, and filled with hit steam. As the steam cooled, it would contract, creating a vacuum. A special carriage would be allowed to enter the tube. This carriage would be mostly a single giant magnet, which would be used to drag a passenger carriage above the vacuum tube. The patent boasted a top speed of 5000 mph.

It's all quite improbable, and beyiond the engineering of the time (if possile at all). But it seems to match the tech levels you are going for.

In addition to the atomic train (which sounds awesome), have you heard of Elon Musk's recently open-sourced project? It's called the "Hyperloop", and it's basically electric carriages accelerated via vacuum IIRC, which I probably don't. One of the cooler things about it is that it would, theoretically, cost about 6-7 billion dollars, as compared to (I think) 50-70 billion that the much-touted "bullet train" would cost. And he believes that even if everything would to go wrong or have been miscalculated leading to double the cost and production time, it would still be a fraction of the cost and time it would take to develop the bullet train.

Also, I'm stealing the atomic train idea (Quick, blinding powder!).

JusticeZero
2013-08-23, 09:26 PM
I'm reminded of the vacuum tube subway that was built illicitly between the Post Office and City Hall back in the 1800s. It proved to not work because of sealing issues. Sounded like a very kooky supervillain plot though.

Trekkin
2013-08-23, 09:51 PM
Nuclear would serve very well, and even in military applications you could use it for things larger than a heavy tank. There are nuclear aircraft engines, I know, and once my NucE friends and I played around with configurations to fit one into a P .1500 Monster.

I'd worry about not having plastics or pharmaceuticals, though, from the lack of oil. How does your setting get around that?

JusticeZero
2013-08-24, 01:14 AM
Well.. I will note that they are making plastics out of things like bananas or algae these days. You can make diesel out of algae too. But if the research is in steam engines, you have path dependence and it won't matter.

TuggyNE
2013-08-24, 04:44 AM
Nuclear would serve very well, and even in military applications you could use it for things larger than a heavy tank. There are nuclear aircraft engines, I know

Well, sort of anyway; I'm not sure they ever got the shielding or efficiency problems quite solved. But for e.g. trains it would probably work rather better, since weight isn't such an issue.

Talya
2013-08-24, 12:33 PM
Steam engines are still a major source of power. You do know that Nuclear power plants are just steam engines with the water heated by a fission reaction instead of burning coal, right?

Autolykos
2013-08-24, 01:49 PM
I am completely for the atomic steam train idea. It melds the awesomeness of steam engines with a higher level of technology nicely.If you use a substance that stays liquid in a larger temperature range than water (molten salts are a good candidate), you could use a gas turbine instead of a steam turbine. That would be lighter, more efficient, and you could regulate power output faster and more easily. I won't go into the reasons why we didn't do it for power plants as this would quickly slide into politics, but for a train, this is the way to go. That is basically the same concept that was tried for aircraft in the 70s, but found inadequate because of the heavy shielding required.

As for organic chemistry, it is mostly a coincidence that we based ours ours on mineral oil. Back then it was cheap, easy to transport and readily available. Without it, we could have just as easily used plant products like vegetable oils, saccharides or alcohol. It is only now with more than a century of chemical research using mineral oil products as a basis that the chemical industry depends on the stuff.

Roxxy
2013-08-26, 12:16 AM
Nuclear would serve very well, and even in military applications you could use it for things larger than a heavy tank. There are nuclear aircraft engines, I know, and once my NucE friends and I played around with configurations to fit one into a P .1500 Monster.

I'd worry about not having plastics or pharmaceuticals, though, from the lack of oil. How does your setting get around that?I understand the plastic part, but I didn't know oil was important to the pharm industry.

Roxxy
2013-08-26, 12:18 AM
If you use a substance that stays liquid in a larger temperature range than water (molten salts are a good candidate), you could use a gas turbine instead of a steam turbine. That would be lighter, more efficient, and you could regulate power output faster and more easily. I won't go into the reasons why we didn't do it for power plants as this would quickly slide into politics, but for a train, this is the way to go. That is basically the same concept that was tried for aircraft in the 70s, but found inadequate because of the heavy shielding required.

As for organic chemistry, it is mostly a coincidence that we based ours ours on mineral oil. Back then it was cheap, easy to transport and readily available. Without it, we could have just as easily used plant products like vegetable oils, saccharides or alcohol. It is only now with more than a century of chemical research using mineral oil products as a basis that the chemical industry depends on the stuff.Well, although I do try for some level of scientific plausibility, I am still running off of some amount of rule of cool. That's why steam got brought up to replace oil, that's why I nuked private transport, and that's why I like the atomic steam engine idea.

Roxxy
2013-08-26, 12:19 AM
Steam engines are still a major source of power. You do know that Nuclear power plants are just steam engines with the water heated by a fission reaction instead of burning coal, right?I know they have steam turbines. Beyond that, I'm not too familiar with the tech.

The Random NPC
2013-08-26, 03:45 AM
Damn it, this is fantasy. I need to start blaming wizards for stuff if I want to get anything cool. Let's use wizardry to make the coal burn hotter and cleaner, and let's also make the spells extremely short duration. Now, in order to get max efficiency, coal needs to burn "in house", as it were, as the stuff is going to be enchanted on site right before use.

So kind of like ghost rock (http://deadlandsclassic.wikidot.com/madscientists)?



With an infernal combustion engine the fuel is sprayed into the engine cylinder chamber and ignited by a small spark. The expanding gas drives the cylinder down.

So is Satan your motor, (http://www.youtube.com/watch?v=-HLF9a1UF6Y) or is Maxwell's demon (http://en.wikipedia.org/wiki/Maxwell%27s_demon)?


Since it matters for this, a quick primer on why we drive gas cars around.
SNIP

Don't forget the car companies buying out and shutting down the tram system to promote car purchases (http://en.wikipedia.org/wiki/General_Motors_streetcar_conspiracy).

Jaycemonde
2013-08-26, 03:57 AM
Steam engines are still a major source of power. You do know that Nuclear power plants are just steam engines with the water heated by a fission reaction instead of burning coal, right?

I was so underwhelmed and disappointed when I learned that as a kid. They're essentially ripping the universe in half inside their reactor and they can't even harness the all-powerful star-explosion energy being generated. (Exaggeration, obviously.) It's just a glorified steam pump.

TuggyNE
2013-08-26, 05:04 AM
I was so underwhelmed and disappointed when I learned that as a kid. They're essentially ripping the universe in half inside their reactor and they can't even harness the all-powerful star-explosion energy being generated. (Exaggeration, obviously.) It's just a glorified steam pump.

Well, I suppose you could stick a Stirling engine on the thing if you really wanted to. But even counting that, fundamentally, nearly all engines are heat engines (electric motors are a notable exception, but they aren't true engines), and so that has the inevitable ramifications.

Still, atomic batteries, at least at low scale, do harness the energy more directly.

Radar
2013-08-26, 09:06 AM
If you use a substance that stays liquid in a larger temperature range than water (molten salts are a good candidate), you could use a gas turbine instead of a steam turbine. That would be lighter, more efficient, and you could regulate power output faster and more easily. I won't go into the reasons why we didn't do it for power plants as this would quickly slide into politics, but for a train, this is the way to go. That is basically the same concept that was tried for aircraft in the 70s, but found inadequate because of the heavy shielding required.
There are reactors with sodium as the coolant in the internal circuit. AFAIK water is used mostly because it's easily available. Besides, Pressurized Water Reactors don't let the water boil in the internal circuit anyway, so there isn't much incentive to use anything else - especially, if you consider, that for example proposed alternatives (like molten salts) are solid in room temperature, so each reactor shutdown and startup is that much more complicated.

Ravens_cry
2013-08-26, 09:47 AM
There are reactors with sodium as the coolant in the internal circuit. AFAIK water is used mostly because it's easily available. Besides, Pressurized Water Reactors don't let the water boil in the internal circuit anyway, so there isn't much incentive to use anything else - especially, if you consider, that for example proposed alternatives (like molten salts) are solid in room temperature, so each reactor shutdown and startup is that much more complicated.
Case in point, the Alfa-class attack submarine. (http://en.wikipedia.org/wiki/Alfa-class_submarine) Fast, fast, incredibly manoeuvrable boat, capable of outrunning torpedoes. but it used liquid lead as its coolant. This meant it literally had to be run all the damn time, with the plans for external heating while in port not exactly going well because of budget problems. It made dismantling the reactors a major hassle when they were being scrapped, being a solid hunk of metal when it cooled.

TheStranger
2013-08-26, 10:45 AM
Fun question. I second the "atomic steam train" idea. Some more thoughts, though:

- I take it private motorized vehicles are either very rare or completely unknown. Which has huge implications on infrastructure - no freeways, no sprawling suburbs, etc. I'd expect denser urban centers, with most growth along existing rail lines.

- What about surface streets? Again, a lot of modern transportation infrastructure isn't really justified without cars. Are you giving those streets over entirely to bicycles (which should be ubiquitous) and pedestrians? Are you building cable cars/trolleys/commuter trains in those spaces?

- How comfortable are people with atomic trains in populated areas? I mean, the devastation if one of them goes off the rails is pretty scary (I don't want to hear about the differences between nuclear reactors and atomic bombs. I demand that a nuclear train crash result in a mushroom cloud). If atomic power generally is pretty safe, you could build giant reactors under major cities and use electric power for a lot of things. Save the giant atomic steam engines for intercity travel.

- Along those lines, and to make sure steam is still ubiquitous - central heating. That giant nuclear reactor is going to generate a lot of heat/steam, so you might as well use it to put radiators in everybody's living room (that's right, your city is now the cooling system for your reactor). Don't worry - the government wouldn't allow it if it was dangerous.

- What's going on in the countryside? Getting electricity out to rural areas isn't a big deal, but what about everything else? You can do a lot with a robust rail system, but people still need to get around on the local level. If I live on a farm, how do I travel 10-20 miles to the nearest rail depot? Horse and buggy? How do I run my farm without a tractor? Or is agriculture a strange patchwork of traditional horse-powered operations and massive industrialized farms operating on a scale that justifies atomic steam tractors?

Ravens_cry
2013-08-26, 10:54 AM
Steam cars were very much a thing. Sure, their range is limited by the need to refill with water, but they are quite doable within those limitations. Steam trains had water stops (http://en.wikipedia.org/wiki/Water_stop), and highways could have something very similar. Simpler in fact, just a little tap and nozzle from the local water mains.

TheStranger
2013-08-26, 11:29 AM
Steam cars were very much a thing. Sure, their range is limited by the need to refill with water, but they are quite doable within those limitations. Steam trains had water stops (http://en.wikipedia.org/wiki/Water_stop), and highways could have something very similar. Simpler in fact, just a little tap and nozzle from the local water mains.

I'm aware - I actually live in the hometown of the guys who made the Stanley Steamer. There's a museum and everything. But steam cars aren't really that much fun, or at least they don't capture my imagination in any significant way. And I think you're missing out on the opportunity to explore some alternate avenues of technological/social development if you make steam cars commonplace.

Joe the Rat
2013-08-26, 11:40 AM
I suppose liquid lead coolant has the advantage of turning into a lump of shielding when it powers down.

Thinking about infrastructure: You're going to see a LOT more pedestrian thoroughfares, but I doubt you will move entirely away from horseless carriages in your cities: there will always be a need for point-to-point transport for material goods. The Electric Phaetons will still be needed to prowl around. (It's either that or horses.) Electric mopeds or Wesson-burning diesoloid motorcycles? Yeah, you could do something with alt-energy motorcycles.

Moving goods from freighter ships (Also atomic!), to railways for major distribution, to... whatever will take the place of tractor/trailers to transport. Shipping containers will likely be sized to fit whatever the to-the-market vehicle is.

Every city will be connected by at least a medium rail, for transport of goods. Every railway will have an adjacent service road, which may or may not be public access. Rail yards will include some damn sophisticated switching methods: If major inter-city transport is expected to be by rail, you should expect personal, private and government owned railcars. Roundhouses are cool. A giant car crane to lift a railcar from one track to another is cooler. It's simply not a proper epic duel unless it's happening on top of a rail car swinging a hundred feet above the atomic railyards.


I was so underwhelmed and disappointed when I learned that as a kid. They're essentially ripping the universe in half inside their reactor and they can't even harness the all-powerful star-explosion energy being generated. (Exaggeration, obviously.) It's just a glorified steam pump.
Personally, I found this kind of awesome because it's a giant radioactive steam engine. It's the early solar plants I was disappointed in for this reason.

Oh! What are you thinking for solar power? Yes? No?

Ravens_cry
2013-08-26, 11:51 AM
I'm aware - I actually live in the hometown of the guys who made the Stanley Steamer. There's a museum and everything. But steam cars aren't really that much fun, or at least they don't capture my imagination in any significant way. And I think you're missing out on the opportunity to explore some alternate avenues of technological/social development if you make steam cars commonplace.
I don't know. They totally capture my imagination. There is a video of Jay Leno showing off his late model Doble steam car (http://www.youtube.com/watch?v=ACO-HXvrRz8) with a heck of a lot of neat little features to make up for some of steams shortcomings. It's such a quiet thing compared to an internal combustion engine, just a soft pottleputt, pottleputt kind of sound, with the soft hiss of steam during braking. Besides, if you don't have them, it raises the question of why not. Steam vehicles were initially kept off the road by railways fearing competition, but this didn't last forever. Electricity, as you mention, is a thing, so, if not steam cars, you could have electric vehicles, which, as you are probably aware, were also a thing, even back then, and the recent efforts on improving their efficiency would likely happen much sooner.

JusticeZero
2013-08-26, 01:36 PM
Steam vehicles were initially kept off the road by railways fearing competition, but this didn't last forever.
Actually, they were kept off the road because they were like mandating that every car keep a thousand pounds of TNT in the trunk as ballast. Steam engines had a tendency to occasionally explode in huge blasts. They eventually solved that, but not before there were a lot of the old engines out there and a bad reputation.

Electric engines exist, yes. However, an extensive road network was not a historical certainty; it was a combination of several public policies combining together combined with the timing of WWII.
Without these policies, the ridiculously expensive street network would not exist in the form we know today:

International highway network - created by Eisenhower modeled after the public works project in Adolph's pre-war Germany, in part as an excuse to spend a lot of money. Roads still only transport a small part of our shipping; they can't take the weight or wear and tear of major shipping.

Anti-monopoly legislation - While a good thing in ways, this hurt the rail networks because previously, they had been expanded by real estate sales and were funded by using the trolly line as a power transmission cable to sell electricity to all the houses along the line.

Great Depression - WWII: When streetcars were invented, huge networks of tracks were created everywhere, and were completely usable as urban transportation. However, they were all new at the same time, and all of them needed to be brought up to date with repairs at the same time - right when everyone was completely broke, or when everyone was sending all the metal to fight on the front.

Federal Housing Authority: After WWII, it was deemed important to put returning soldiers into houses. A government financing system was created to help fund this, and was based on a variety of principles: It would lend lots of money to people moving into "Good" neighborhoods, and would not give any money to fix up houses in "Bad" neighborhoods. "Bad" neighborhoods had the following properties: There were houses in the neighborhood that already existed - nobody could afford to move into the city that was already there - and there were "people of color" (a wide variety of minorities) living in the neighborhood. (Just one was enough to make the banks start denying all the loans.)
Since the streetcar companies weren't given the chance to sell the land to fund tracks - that was the traditional way to fund rail lines - public funds - the traditional way to fund road lines - were used to build streets.
Furthermore, the houses built had to be nowhere near businesses, single family detached houses that ate up surface area like crazy.

Voting on bond improvements: After all of those neighborhoods were put in, they had to vote on whether to fund repairing streetcar lines. As noted, most of the people voting now lived in neighborhoods that had no streetcars.

The result is that we now have a hideously expensive to maintain highway network instead of a merely very expensive to maintain rail network over a smaller area.

Sith_Happens
2013-08-26, 02:22 PM
http://24.media.tumblr.com/33102f3a477a55a1f694c991009392f5/tumblr_mmcw8mofwG1r5xzspo1_400.jpg

Autolykos
2013-08-27, 04:29 AM
Well, if you want the more classical steam engines in your nuclear trains, that's quite easy to justify. Without oil, there won't be much incentive to develop jet engines or gas turbines. If the most efficient known way to convert heat into motion is by boiling water, you don't need to get much hotter than 100C anyway. And you can do that quite easily by putting some nuclear fuel in your water boiler (the difficulties start afterwards).

Pressurized Water Reactors don't let the water boil in the internal circuit anyway, so there isn't much incentive to use anythingLots of technical, slightly off-topic stuff, therefor spoilered:
Boiling or not is not actually the important point. It's all about the temperature difference, since that limits the efficiency of your engine (no matter how it works in detail). With water, you won't exceed ~300C (and that's at pressures of over 150 bar, which is a massive issue right there that requires a lot of good engineering to make even remotely safe). Molten salt can easily get you up to 1500C at atmospheric pressure. It may be more expensive to build, maintain and dismantle, but it is inherently safer and more efficient.
The concept of chaining a water circuit to a sodium circuit kinda combines the disadvantages of both worlds (plus the added fun of having tons of sodium next to tons of water). That's because it is done for entirely different reasons (namely, using the fast neutrons to breed more fuel).
And while it's true that switching metal-cooled reactors (like in subs) on after letting them cool down is a major PITA, it is not dangerous to cut power to them and let them cool down. Water-cooled reactors, OTOH, need to be cooled constantly (and basically for as long as there's fuel in them), or they will get very dangerous very quickly (see also: Fukushima).