Highest point a society could develop without fossile fuels

[Ariphaos]

I'm still trying to wrap my mind around where the copper is going to come from, and how it's going to be formed into any meaningful quantity of wire. There sure isn't a lot of native copper around, and (I'm probably making this up in my head) I thought a lot of the more abundant copper ores were made to be useful through electrowinning and other magic voodoo processes. Those won't do you much good if you don't already have electricity, of course.

Electrowinning is only required in the case of aluminum, as far as I know.

[Howedar]

I don't know what it's required for, per se, but I know it's heavily used in the copper industry.

[Darth Wong]

Dude, they smelted copper and tin in order to make bronze during the Bronze Age.

[Ariphaos]

Dude, they smelted copper and tin in order to make bronze during the Bronze Age.

He specifically mentioned native copper so he might have been under the impression that that's all they used.

[AMX]

Europe has diesel aircraft engines that could, at least in theory, run on biodiesel. They are dependent on computerized fuel/air engine feeds, which may or may not be feasible in this hypothetical world.

There were diesel powered aircraft in the '30ies. Not much computerisation back then.

Brazil runs agri-industrial crop dusters on pure ethanol. The problem is that nothing has the energy density of petro-fuels, but if you're willing to burn more fuel for the same result heavier-than-air flight with alternatives is possible.

Actually, biodiesel has almost exactly the same energy density as gasoline (both ~8.9kWh/l), and straight vegetable oil is slightly above that (9.2kWh/l) although still inferior to jet fuel (9.5) and diesel (9.8).
Of course, ethanol is nowhere near that (5.9kWh/l), which may be where biofuels get that "inferior energy density" rep.
(All figures from a superficial Google search.)

[Walsh]

Even if you have nothing more than primitive iron blades on waterwheels connected to hand-wound copper wire generators, you could make electricity. Not as efficiently as a modern hydroelectric dam, but you could make electricity nonetheless.

I'm still trying to wrap my mind around where the copper is going to come from, and how it's going to be formed into any meaningful quantity of wire. There sure isn't a lot of native copper around, and (I'm probably making this up in my head) I thought a lot of the more abundant copper ores were made to be useful through electrowinning and other magic voodoo processes. Those won't do you much good if you don't already have electricity, of course.

I almost wonder if very initial attempts would be better off using gold. Generally less chemically tied up than copper, and ductile as dog poo.

Just a nitpick, but electrowinning is only used on very low-grade (usually already-processed) copper ores to 'squeeze out the last few drops'. As DW mentioned, there are shit easy ways to get copper from very rich ores, all you need is a hole in the ground, rocks, a few animal skins, and sufficient-grade ore.

Gold would be fine, but its value is bound to exclude its use in very early attempts.

What about hydrazine + hydrogen peroxide as a wartime plane fuel? It's been years since I studied this, but I think the Germans made good, albeit limited, use of it. Besides, if the other guys don't have planes of their own, it would be a lethal edge.

[wolveraptor]

I was assuming the age of the carbon-producing biosphere, but yes, though, as I understand it the Solar System formed very quickly after the parent supernova and I would imagine that this is not always the case, leading many worlds to be formed with a lot less tectonic potential.

The biosphere used to have a lot more oxygen in it than it does now. When most of the coal and oil we use today was being formed (in the Carboniferous), the oxygen comprised close to 40% of the world's atmosphere, if I'm not mistaken. That could be an interesting caveat, if you want to include it into your scenario.

[aerius]

I'm still trying to wrap my mind around where the copper is going to come from, and how it's going to be formed into any meaningful quantity of wire. There sure isn't a lot of native copper around, and (I'm probably making this up in my head) I thought a lot of the more abundant copper ores were made to be useful through electrowinning and other magic voodoo processes. Those won't do you much good if you don't already have electricity, of course.

Humans were already smelting copper thousands of years ago using open hearth furnaces and crucibles. All you need to do is find some decent quality ore and turn some trees into charcoal, it's something you could probably do in your backyard on a small scale. We don't need 99.99% pure copper for the generator coils, 90% or so will do quite nicely and that can be done with smelting alone.

As for making the wire, if we can make some steel rollers and dies we're all set, and the copper wire can be cranked out by the mile. Once the generators are running, everything else becomes a lot easier.

[Broomstick]

Europe has diesel aircraft engines that could, at least in theory, run on biodiesel. They are dependent on computerized fuel/air engine feeds, which may or may not be feasible in this hypothetical world.

There were diesel powered aircraft in the '30ies. Not much computerisation back then.

The modern diesels use the computers to make them more fuel-efficient. I am not conversant with 1930's diesels compared to those of 2007. I do, however, have experience with piston/gasoline engines utilizing both 1950's/60's carbeurator technology and modern computerized/fuel injection engines. The second choice burns 2/3 to 1/2 the fuel per hour as the older technology does in the same airframe. That's quite a difference

Better design, often very subtle changes in wingfoil and fuselage shape, can also result in much greater efficiency.

Is it nice to have the energy density of gasoline to work with? You bet. Is it necessary? No, it's not. I'm not sure what "least efficient" fuel would still result in a viable airplane, but given sufficient incentive I'm sure we can find out.

Of course, ethanol is nowhere near that (5.9kWh/l), which may be where biofuels get that "inferior energy density" rep.

And yet, there are airplanes used in industrial applications utilizing that very fuel.

So I would conclude that in this hypothetical world aircraft, automobiles, engine-driven ships, and trains are all feasible. There would of course be the problem of producing sufficient fuel for all the desire applications, which may affect how many such machines exist and how they are used.

[Howedar]

Dude, they smelted copper and tin in order to make bronze during the Bronze Age.

Yeah, that should probably have occurred to me. I knew that skipping out on Age of Empires would come back to bite me.

[Broomstick]

What about hydrazine + hydrogen peroxide as a wartime plane fuel? It's been years since I studied this, but I think the Germans made good, albeit limited, use of it. Besides, if the other guys don't have planes of their own, it would be a lethal edge.

If you're referring to the Messerschmidt 163 Komet there were a few problems. Like, blowing up on the flight line for no explicable reason. Blowing up in flight frequently. The fuels used were highly corrosive, requiring special suits for the safety of both ground crew and pilots. Fuel leaks could result in human flesh being dissolved and if I recall a couple people met their ends that way. Learn about the Komet program and you'll figure out why the Germans didn't hesitate to use hydrogen in zepplins - it was so much safer than what they put in the Komet...

The Komet was successful in that it flew, but a lot more blew up in malfunction than were shot down in combat. Still, if there were no alternatives a civilization might come up with a more controlled version of this system.

[The Duchess of Zeon]

Dude, they smelted copper and tin in order to make bronze during the Bronze Age.

Before that, they used copper by itself.

It's commonly said that the New World was a stone-age society, but in addition to the working of the precious metals (which are very easy to work), they also had copper--and used it for things like arrowheads, in the case of a few civilizations. The Ancient Egyptians in the very early periods were also pre-bronze, and just used copper.

Copper is literally the first metal that primitive human societies start to exploit.

[The_Saint]

The Komet fuel system isn't a great idea.. both fuel's aren't easy to make and store... hydrogen peroxide is highly corrosive so it requires very specific storing conditions that were barely possible under wartime conditions. It was considered a killer by German pilots of the time as well as Allied test pilots after the war... and they weren't referring to it's combat capabilities.


Almost any other fuel system up to and maybe including atomic power is safer.