no fusion power Traveller
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mike wightman
SOC-14 10K
No fusion power you say, what about gravitics?
Assuming the Falcon heavy and the BFR cut the costs of getting stuff into space, followed by the successful development of the Skylon space plane, and you will get space industry.
Solar power satellites provide the energy needs of the space industries.
Ships in the inner solar system and on the transport network will be a mixture of ion drives and solar sails powered by lasers. For deep space ships that need to go off the laser transport infrastructure then fission power plants can power the ion engines/plasma rockets that provide their motive thrust.
Assuming the Falcon heavy and the BFR cut the costs of getting stuff into space, followed by the successful development of the Skylon space plane, and you will get space industry.
Solar power satellites provide the energy needs of the space industries.
Ships in the inner solar system and on the transport network will be a mixture of ion drives and solar sails powered by lasers. For deep space ships that need to go off the laser transport infrastructure then fission power plants can power the ion engines/plasma rockets that provide their motive thrust.
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epicenter00
SOC-13
What if it didn't look that different?
It's theorized the Romans never advanced as much in realms such as automation and other labor-saving devices because the ready access to slaves made it unnecessary to develop. There's more solid evidence that during certain times in China, after wars and plagues, textile weaving in had various automation and labor-saving devices due to the shortage of workers. However, as the population bounced back, these devices stopped being used because it was cheaper to just use the more plentiful human workers.
Overcoming limits is the major impetus to the development of technology. Traveller computers, grav plates, and other currently power-hungry devices would become more efficient as they don't have the crutch of fusion power. Certain power hungry devices likely would not be possible. Like even with more efficient grav-plates, there might be practical limits to how much weight they could support or for how long, leading to some sort of upper limit to how large of a starship could make interface landings/takeoffs. This might truly justify the idea of "lighters" or similar smaller vessels to unload merchants that remain in orbit; large ships might be able to make liftoff using "tugs" which would be ships with enormous banks of capacitors, perhaps. Anti-gravity cities and floating palaces would likely no longer be a thing.
The power requirements of Traveller lasers suggest they they are some sort direct-power system. It's more likely without fusion power to supply their enormous power needs, lasers would be chemical in nature, requiring one-use cartridges; in their function at the abstract Traveller game level, their effects probably wouldn't change.
Obviously, fusion guns would vanish. I'd actually hazard to guess that plasma guns might vanish as well, but perhaps not.
Overall, I think Traveller would lose one of the things that make it the "magical space opera future" if you lose fusion. If this is a good or a bad thing to you is up to you.
Of course, intermediate versions of this are possible. Like what if fusion is possible, but practical fusion for power generation only exists in huge, static reactors. A 200 dton ship isn't going to have fusion reactor. Certainly not a grav tank. Battleships might be huge simply because they're the smallest vessel that can fit a fusion reactor in it.
AnotherDilbert
SOC-14 1K
No fusion, no power for jump drives.
We are left with something like The Expanse...
We are left with something like The Expanse...
Enoki
SOC-14 1K
If you still have jump drives, it is possible to run these off other power sources. Most are rather bulky but it could be done. For example fission is still possible, and the rules as written don't really do this method justice as you can fit a rather powerful reactor in a much smaller area than they allow.
Even in the 50's it was possible to put a running one in an airplane to power it. Here, I'd think they'd have better technology for fission and use that instead.
If jumping involves a momentary impulse of massive power then there are several alternatives that could make that happen like using a superconducting generator that's much more compact for the energy produced than conventional ones.
All of these would make the ship much more bulky and probably limit the jump to 1 or 2, but that's better than nothing...
Even in the 50's it was possible to put a running one in an airplane to power it. Here, I'd think they'd have better technology for fission and use that instead.
If jumping involves a momentary impulse of massive power then there are several alternatives that could make that happen like using a superconducting generator that's much more compact for the energy produced than conventional ones.
All of these would make the ship much more bulky and probably limit the jump to 1 or 2, but that's better than nothing...
I tend to agree with AnoderDilbert here.
Another possibility would be to only partially control the Fusion power, somewat aas being able to maintain for limited time a fusión reaction, enough to jump, but not being able to control it for long enough as to allow it to produce power o na sustained basis.
Time ago I more or less hinted this in the thread Marginal Early Stellar TL Frigate. It was initially designed as MT design, where the design system is quite inefficient (in all fuels, I guess), and latter converted to MgT, where things are more logical in this sense.
This is more or less what happens in 2300AD...
Another possibility would be to only partially control the Fusion power, somewat aas being able to maintain for limited time a fusión reaction, enough to jump, but not being able to control it for long enough as to allow it to produce power o na sustained basis.
Time ago I more or less hinted this in the thread Marginal Early Stellar TL Frigate. It was initially designed as MT design, where the design system is quite inefficient (in all fuels, I guess), and latter converted to MgT, where things are more logical in this sense.
This is more or less what happens in 2300AD...
Timerover51
SOC-14 5K
I keep looking at the idea of a universe where fusion plants are not small, so that it takes something like a 100 dTon Scout or so to carry one, with no plants for smaller vehicles. Basically, you would still be using chemical-energy power plants for most of your smaller vehicles, or high-efficiency radio-isotope thermal generating units. The main reason for this is how do you handle the heat generated by producing large amounts of power in a small space. Either you have a fantastically efficient converter from fusion power to electricity, with no intermediate heat exchanger, or something like Piper's "nuclear-electric battery converter" where you go from radiation to electricity in one step.
I could live with fission plants powering ships, as those already exist in your nuclear submarines. It would require breeder reactors to produce either plutonium from U-238 or uranium-233 from thorium-232, but that technology also already exists.
Going back to the 1977 rules for spaceships, I size the power plant to the maneuver drive, do a boost and coast to the Jump Point, and spend the coast period charging the jump capacitors. In my system, a large portion of the Jump Drive volume is actually massive capacitor banks to supply the energy jolt to enter Jump Space. That explains the mathematical progress of larger Jump Drives. The cost per ton should decrease as the drive gets larger though, rather than increasing.
I could live with fission plants powering ships, as those already exist in your nuclear submarines. It would require breeder reactors to produce either plutonium from U-238 or uranium-233 from thorium-232, but that technology also already exists.
Going back to the 1977 rules for spaceships, I size the power plant to the maneuver drive, do a boost and coast to the Jump Point, and spend the coast period charging the jump capacitors. In my system, a large portion of the Jump Drive volume is actually massive capacitor banks to supply the energy jolt to enter Jump Space. That explains the mathematical progress of larger Jump Drives. The cost per ton should decrease as the drive gets larger though, rather than increasing.
AnotherDilbert
SOC-14 1K
Routine power from the PP could easily be provided by fission, even if is gigawatts.
But the jump fuel is fused to provide the energy for the jump. That cannot be replaced by fission.
If we take a CT HG drives as example, say 100 Dt, J-1, M-1, PP-1.
The power plant produces 250 MW for 4 weeks from 1 Dt fuel. That is 250000000 × 4 × 7 × 24 × 300 ≈ 600 TJ from 1 Dt fuel.
The jump takes 10 Dt fuel in a few minutes, but is probably less efficient, perhaps 2000 TJ (roughly a ½ megaton nuke). No ship-sized fission plant can produce that much power that fast. It would take something like a few TW, as much power as a few thousand nuclear power plant reactors produce.
Unless you suggest that we set off a nuke inside the ship and somehow transform the explosion into usable energy, say electricity, jumping would require massive external power systems.
But since drop tanks are possible, why not external power systems? It would be a one way trip though...
mike wightman
SOC-14 10K
If you are postulating no fusion power you are changing the setting, you are not limited to T5 or any other OTU/3I setting detail.
You can therefore handwave the jump drive may be powered by solar cells or fission power plants or whatever you want. Or go with alternative FTL systems altogether.
The important difference is gravitics. No m-drive, artificial gravity plates and acceleration compensation means real world space craft engines - chemical rockets, nuclear (various methods involving fission), ion engines, plasma rockets, light sails etc.
Getting out of a sizable gravity well costs. Establish a space based industry and build your infrastructure for spacefaring craft in orbit using materials mined from the moon and asteroids. Build orbital habitats, L4 habitats, asteroid habitats, a moonbase.
You can therefore handwave the jump drive may be powered by solar cells or fission power plants or whatever you want. Or go with alternative FTL systems altogether.
The important difference is gravitics. No m-drive, artificial gravity plates and acceleration compensation means real world space craft engines - chemical rockets, nuclear (various methods involving fission), ion engines, plasma rockets, light sails etc.
Getting out of a sizable gravity well costs. Establish a space based industry and build your infrastructure for spacefaring craft in orbit using materials mined from the moon and asteroids. Build orbital habitats, L4 habitats, asteroid habitats, a moonbase.
T5 says there are other ways to power jumps.
Enoki
SOC-14 1K
Even a large superconducting generator could provide megawatts to possibly gigawatts of power and be reasonably sized. Superconduction would be possible in space and you could use alternative fuels and systems to run it if all you need is X amount of power available for a brief period. One method would be something like an OTTO fuel turbine to provide the motive power for the generator.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660010307.pdf
That's 1966!
A fission plant providing say superheated steam of some sort could possibly work too, so long as the pressures and temperatures are manageable. That would depend on the materials available to the designers and builders.
So, there are already conventional systems that could generate mega to gigawatts of electrical power that are more than theoretically possible in a space craft of the sort found in Traveller.
While these would be far less compact than using fission, they would work.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660010307.pdf
That's 1966!
A fission plant providing say superheated steam of some sort could possibly work too, so long as the pressures and temperatures are manageable. That would depend on the materials available to the designers and builders.
So, there are already conventional systems that could generate mega to gigawatts of electrical power that are more than theoretically possible in a space craft of the sort found in Traveller.
While these would be far less compact than using fission, they would work.
AnotherDilbert
SOC-14 1K
We don't need gigawatts, we need terawatts (a thousand of times more).
The minimum jump on a minimum ship require something like 2000 TJ to enter jump.
The best chemical fuels we know has an energy density of about 100 MJ/kg, so to get 2000 TJ = 2 000 000 000 MJ we would need to burn 2 000 000 000 / 100 = 20 000 000 kg = 20 000 tonnes of fuel plus a reducing agent, e.g. oxygen. If the fuel is liquid hydrogen that is 20 000 Dt fuel plus another 10 000 Dt liquid oxygen (at an unlikely 100% efficiency) to jump a 100 Dt ship.
Chemical fuels just won't power jump.
Condottiere
SOC-14 5K
It depends on how each edition rules on jump drive ignition.
In Mongosianspace, all you need are enough batteries, which you can charge with a solar panel, pretty much like your cell phone.
In Mongosianspace, all you need are enough batteries, which you can charge with a solar panel, pretty much like your cell phone.
kilemall
SOC-14 5K
Alright, here is a key question- what game effect are you shooting for with declaring no fusion power?
Correlating question, are all other design elements and values defined for whatever version locked in place, or subject to change?
Or is this not gameplay at all, just to spark speculation on what happens to the setting with this primary technology unavailable?
Correlating question, are all other design elements and values defined for whatever version locked in place, or subject to change?
Or is this not gameplay at all, just to spark speculation on what happens to the setting with this primary technology unavailable?
Enoki
SOC-14 1K
Doesn't that apply to the Annic Nova ship too...?
It is possible that the collector isn't collecting electricity but some exotic particle.
How does a steam plant work without gravity?
once you get it going, you have a turbine keeping the flow pressurized.
Or a reciprocating system with pistons on both sides of the heating; the injection piston's timed to retreat with the power take-off piston as the water it injected expands, then is vented to cooling as both are driven in by other piston's in different parts of the cycle.
Oh, and Larry Niven came up with a low tech method: Large water tank, small fire around the exit tube. After the initial shove-off, water is sloshed into the tube, expands, escaping out the back and pushing the water forward, which sloshes, and as the steam escapes is allowed to fall back, and repeat the cycle.
