Using High Efficiency Batteries for Jump Drives

[Terry Mixon]

Sure, but it is a flatly nonsensical statement Power from a fusion plant is not different in kind from power from a fission plant or a gas turbine.

The half-arsed explanation for why fusion plants can power jump in other editions is that they "overclock" and produce orders of magnitude more power for the short time necessary to produce a jump bubble.

Batteries obviously don't do that. Even assuming future tech batteries merge with capacitors to provide the best of both. Once you let batteries power jump, you don't have any legitimate argument for disallowing fission plants from doing so.

I can't argue that logic, yet here we are. Bring on the solar powered, battery enabled jump drives!

 

[Vormaerin]

I can't argue that logic, yet here we are. Bring on the solar powered, battery enabled jump drives!

hey, the sun's a fusion reactor isn't it?

 

[Terry Mixon]

hey, the sun's a fusion reactor isn't it?

#truth

I suppose we need a bicycle-powered jump drive. They might be there a while.

 

[Condottiere]

I had a go at that - you run out of battery juice for life support in jumpspace.

There are ways around it, that the crew and passengers aren't likely to appreciate.

 

[Fluffy Bunny Feet]

GDW Traders and Gunboats 1980 is the oldest Xpress Boat I can find. It has NO power plant as the jump drive provides all needed power. "Power Plant: None. Jump drives carry power plant capacities and functions."

Even a Free Trader can benefit from batteries for jump. Use a budget jump drive reducing its price by 25% (saving 3.75 MCr on the drive) and increasing power required by 30%. Covering the extra power with a battery is much cheaper than by an extra ton of power plant and the big savings on the jump drive makes it worthwhile even without the power plant savings.

A couple of tons of battery can also power multiple weapons firings to persuade an opponent who doesn't know they are battery powered to break off or surrender.

 

[rinku]

It's the Jump Drive itself that's doing the extra special space magic work on the jump fuel, whether that be fusing it rapidly, inflating it into a jump bubble, using it as reaction mass to fling the ship through Jump Space or whatever, but it has an external power requirement on top of that. That could come from a fusion plant, fission plant, solar panels, batteries or whatever.

The precedent of X-Boats pretty much confirms this is a peak power requirement ONLY at Jump. Once inside Jump Space it's back to base hull power requirements.

Worth noting that the original X-Boat has a lot of tonnage assigned to (at the time) non-standard stuff like communications arrays and data storage. So does it have extra batteries too? Probably, but it can be rolled into the rest of the special allocation.

Also, there's an interesting note there that "Ship can operate automatically without any crew."

 

[Condottiere]

1. I think that originally, the jump drive worked continuously for a week, and the residual power could be tapped for basic services, such as they are.

2. I do believe the restriction about solar panels deployment during jumping, has been withdrawn.

3. Which seems to be the greenlight to allow solar panels to directly power the jump drive.

 

[Terry Mixon]

It's the Jump Drive itself that's doing the extra special space magic work on the jump fuel, whether that be fusing it rapidly, inflating it into a jump bubble, using it as reaction mass to fling the ship through Jump Space or whatever, but it has an external power requirement on top of that. That could come from a fusion plant, fission plant, solar panels, batteries or whatever.

The precedent of X-Boats pretty much confirms this is a peak power requirement ONLY at Jump. Once inside Jump Space it's back to base hull power requirements.

Worth noting that the original X-Boat has a lot of tonnage assigned to (at the time) non-standard stuff like communications arrays and data storage. So does it have extra batteries too? Probably, but it can be rolled into the rest of the special allocation.

Also, there's an interesting note there that "Ship can operate automatically without any crew."

The rules say the power has to originate with fusion or antimatter power plants, and that is only needed at the moment of jump.

 

[rinku]

The rules say the power has to originate with fusion or antimatter power plants, and that is only needed at the moment of jump.

Well, the High Guard revision introduces that line (it's not in the core book, or the 2016 High Guard or CT, or any previous edition I've been able to check)... but then allows the X-Boat to ignore it and jump off batteries anyway.

Giant capacitors that allow a rapid discharge of energy to allow Jump have, however, been a thing since CT High Guard. It makes more engineering sense that the powerplant charges those up over time to allow a peak output than otherwise.

So... for reasons of continuity and common sense I choose to ignore that line about *needing* fusion or antimatter, and reframe it as those just being the most practical ways to provide the power needed in the time required. Solar might technically be able to charge up the batteries, but not quickly. Fission can do it but is far bulkier than fusion and needs a different fuel than the Jump Drive.

 

[Terry Mixon]

Well, the High Guard revision introduces that line (it's not in the core book, or the 2016 High Guard or CT, or any previous edition I've been able to check)... but then allows the X-Boat to ignore it and jump off batteries anyway.

Giant capacitors that allow a rapid discharge of energy to allow Jump have, however, been a thing since CT High Guard. It makes more engineering sense that the powerplant charges those up over time to allow a peak output than otherwise.

So... for reasons of continuity and common sense I choose to ignore that line about *needing* fusion or antimatter, and reframe it as those just being the most practical ways to provide the power needed in the time required. Solar might technically be able to charge up the batteries, but not quickly. Fission can do it but is far bulkier than fusion and needs a different fuel than the Jump Drive.

I hear you.

 

[rinku]

On a historical note...

1977 Book 2 did not require a power plant for a J-Drive. It only mentioned that the PP had to be rated at least as good as the M-Drive. The original X-Boat concept seems to have been a 100 ton standard hull with its 15 ton engineering section filled with a B class J-Drive, which was a legal design at the time. The 40 tons fuel, two (!) staterooms, bridge, computer (Traders and Gunboats, 1980, gives both Model/4 in the text and Model 1/bis in the summary, but under Book 2 rules either could have run Jump 4, and there's only 3 tons difference anyway), and single ton of cargo do fit into the 85 ton main compartment with some tonnage to spare for the special electronics. Or batteries.

By the time of the 1981 revised rules, J-Drives did require a power plant of the same or better rating, and it has been so ever since... except for X-Boats...

 

[Condottiere]

Capacitors can be over capacitated, currently, by one hundred fifty percent.

I don't recall what the current leak rate is.

 

[Sigtrygg]

Annic Nova is an edge case, but I believe it's still accumulating hydrogen and storing it as jump fuel?

No, the Annic Nova needs no hydrogen for a jump, which is why the MgT description of a hydrogen filled jump bubble is contradicted within their setting.

 

[Sigtrygg]

There are restrictions on power sources in Mongoose Traveller.

Which are contradicted by collectors and now batteries...

And then in the batteries section:

So you charge the battery with a fission of chemical plant...

I'd imagine the bolded part is the justification for using batteries to power jump, so long as the right kind of power plant generated the hot dogs, er, power. It's the justification I was using, anyway.

Electricity is electricity, batteries store energy, how you fill the battery is immaterial to electricity flowing from the battery to the jump drive.

 

[Sigtrygg]

It's the Jump Drive itself that's doing the extra special space magic work on the jump fuel, whether that be fusing it rapidly, inflating it into a jump bubble, using it as reaction mass to fling the ship through Jump Space or whatever, but it has an external power requirement on top of that. That could come from a fusion plant, fission plant, solar panels, batteries or whatever.

The Annic Nova and other collector equipped ships do not need jump fuel.

The hydrogen filled jump bubble was introduced in T4 due to authors either including their own fanon or misreading what was written in the MefaTraveller SOM.

The setting already makes it very clear, as does Marc's jump space article, that there is no hydrogen filled jump bubble.

Also, there's an interesting note there that "Ship can operate automatically without any crew."

Which is contradicted by the fanon made canon that is creeping into MgT Third Imperium that you need a sophont on board to jump.

 

[Sigtrygg]

Capacitors can be over capacitated, currently, by one hundred fifty percent.

Overloading a capacitor has another name - a firestarter.

We used to do it in physics lab for laughs...

 

[Condottiere]

Water memory is the purported ability of water to retain a memory of substances previously dissolved in it even after an arbitrary number of serial dilutions. It has been claimed to be a mechanism by which homeopathic remedies work, even when they are diluted to the point that no molecule of the original substance remains, but there is no theory for it.

 

[Condottiere]

Jump drives cannot be engaged with solar panels deployed.


I can't seem to find this sentence in the High Guard update.

 

[Sigtrygg]

Water memory is the purported ability of water to retain a memory of substances previously dissolved in it even after an arbitrary number of serial dilutions. It has been claimed to be a mechanism by which homeopathic remedies work, even when they are diluted to the point that no molecule of the original substance remains, but there is no theory for it.

That's because it is bollocks.

 

[Condottiere]

Quantum entanglement is the phenomenon where the quantum state of each particle in a group cannot be described independently of the state of the others, even when the particles are separated by a large distance.


If we combine these two concepts, it might explain why energy remembers from which source it sprang from.

Hence, the requirement for fusion reactors to power jump drives.