How do Honorverse ships generate their energy?

Ok, now bear with me. I know that on first view, the answer seems straight forward, right?
What they get their energy from? Well, fusion (and fission, in case of LACs) reactors, obviously! Duh!

But... there's a problem. Or rather - a missing step. You have a fusion/fission reactor. It fuses/fissures atoms, creating heat and radiation. Both are forms of energy, but in general, neither heat or radiation are useful to do anything with it (beyond heating/irradiating stuff). How do you convert that into electric (or whatever) energy drive nodes need? Or for that matter, grasers?

In our world, a fusion/fission reactor does this by heating water. The water is then fed through a turbine which powers a generator which generates electricity. So we convert thermal energy to kinetic energy and then to electric energy.

But how is this energy conversion done in a starship? For some reason I find it... hard to believe that a Manty superdreadnought or a Grayson LAC have steam turbines churning deep inside their engine rooms... not only does this appear to be a bit too anachronistic, I also seriously doubt that any turbine-powered generator would be able to generate enough electricity to power a Graser battery which is able to "shatter a small moon" (quote from the books).

Obviously there's some sort of magical generator device which is able to turn heat and radiation directly into electrical (or whatever) energy. Does anyone have a clue what that might be?

It is worse than that, because the energy capacitors that power many things store plasma. So the main output of the fusion (or fission) reactors is plasma that can be stored to power missiles etc. On the LAC the capacitors also power the energy weapons and bow or stern walls. Until the new miniature fusion reactors, pods and their missiles all had to be supplied with plasma just before use. The fusion reactors that use artificial gravity all have to be supplied with plasma at startup. We do not know how this all works, unless it it is magneto-hydrodynamics converting plasma directly to electricity.

On very small scale we do have a way to convert radioactivity to electricity: the radioisotope battery, but I do not see that as relevant to your question. Except that the use of steam is not the only way we get power from fission in our time. From Wikipedia:

The thermal types convert some of the heat generated by the nuclear decay into electricity. The most notable example is the radioisotope thermoelectric generator (RTG), often used in spacecraft. The non-thermal converters extract energy directly from the emitted radiation, before it is degraded into heat. They are easier to miniaturize and do not require a thermal gradient to operate, so they are suitable for use in small-scale applications. The most notable example is the betavoltaic cell.

The non-thermal generator can use either alpha or beta emission.

Mini-fusion reactors need plasma to start. That's why the plasma conduits run to the Mk16 and Mk23 launchers on ships. There are also plasma capacitors running to energy weapon launchers. It's been stated somewhere that a recon drone or missile can't restart their reactor if they shut it down.

So there is a web of plasma pipes running through the ship, each holding essentially the core of a star.

What could possibly go wrong?

As to how you go from plasma to electricity, this is very much not defined. I have no idea why star core pipes are a better idea than superconducting cables, but David clearly has a reason.

Okay, but those plasma tubes only move the problem a step away. Now we have plasma at the gun mounts, but how do we turn plasma into focused gamma radiation?
More than that, how do you get plasma from a fission reactor? Any plasma in a fission pile is a very bad thing since it's essentially a meltdown - fission piles work by having a veeeery carefully calculated geometry of their fuel rod assemblies. If those same fuel rods became a plasma, you'd be in deep shit...

Classified handwavium.

clancy688 wrote:Okay, but those plasma tubes only move the problem a step away. Now we have plasma at the gun mounts, but how do we turn plasma into focused gamma radiation?
More than that, how do you get plasma from a fission reactor? Any plasma in a fission pile is a very bad thing since it's essentially a meltdown - fission piles work by having a veeeery carefully calculated geometry of their fuel rod assemblies. If those same fuel rods became a plasma, you'd be in deep shit...

The fission rods themselves are not turning into plasma, instead it is the gas coolant (helium?). I mentioned magneto-hydrodynamics converting plasma directly to electricity; if you have a plasma pipe with an anode on one side and a cathode on the other, with a very strong magnetic field between top and bottom; then you move the plasma quickly through it, the ions will move to one side and the disassociated electrons to the other giving yourself a big voltage difference between the anode and cathode. I believe the wattage of the device is related to the magnetic field strength and the speed of the plasma. You obviously will have a heating problem with the anode and cathode, but that is something that can be engineered away. I do not know if that is what the author intended, but that is one solution.

Give up the ghost trying to figure out the plumbing. I did long ago.

Some of us have a problem with the reactors. The capacitors give me a headache. Some of us have a problem with power cords. And what's with plasma coursing thru the veins of the entire ship. IINM, we have had a case of a ship streaming plasma. It was vented to the outside, I suppose. But can you imagine the destructiveness of a plasma leak aboard ship. One of my friends said long ago that plasma leaks are contained because of the use of "monster cables." He owns a high-end audio company.

kzt wrote:Mini-fusion reactors need plasma to start. That's why the plasma conduits run to the Mk16 and Mk23 launchers on ships. There are also plasma capacitors running to energy weapon launchers. It's been stated somewhere that a recon drone or missile can't restart their reactor if they shut it down.

So there is a web of plasma pipes running through the ship, each holding essentially the core of a star.

What could possibly go wrong?

As to how you go from plasma to electricity, this is very much not defined. I have no idea why star core pipes are a better idea than superconducting cables, but David clearly has a reason.

cthia wrote:Give up the ghost trying to figure out the plumbing. I did long ago.

Some of us have a problem with the reactors. The capacitors give me a headache. Some of us have a problem with power cords. And what's with plasma coursing thru the veins of the entire ship. IINM, we have had a case of a ship streaming plasma. It was vented to the outside, I suppose. But can you imagine the destructiveness of a plasma leak aboard ship. One of my friends said long ago that plasma leaks are contained because of the use of "monster cables." He owns a high-end audio company.

I assume that there is only plasma in the conduits as needed, for example: when there is no enemy in sight; the capacitors for the grasers and PDLC's are full, but their supply conduits are empty. The conduits supplying plasma to the capacitors for missile tubes are also empty. Basically there is a capacitor for every piece of equipment that requires a big surge, but outside of combat the supply conduits can be empty and perhaps there are situations (even in wartime) when some or all of those capacitors can be empty also.

I also assume there are redundant internal electrical lines that supply power to the lights, electronics and so on; rather than each of them having to convert plasma to electricity.

Energy and warships in the HV is simply the stuff of nightmares. You need a few aspirins and a good shrink.

HV ships seem to use a lot of energy. A lot. And they seem to somehow create a lot. A lot. And most of it seems to be wasted.

Reactors seem to drive these wonder capacitors. If I ever make it to the HV and I decide to take up a career in espionage, I'll begin with the capacitors.

But the wedge is probably the most fascinating of all. There we have gobs of energy that can act like a waste dump and absorb excess heat. And it can destroy anything it comes into contact with. But it has absolutely no ability to power anything.

And particle shielding. I still have my disbelief on suspension. Things in the HV travel at .8C, and they can swat enormous pieces of debris away. That would require a tremendous amount of energy.

Are there many sci-fi works whose warships are not powered by handwavium?

cthia wrote:But the wedge is probably the most fascinating of all. There we have gobs of energy that can act like a waste dump and absorb excess heat. And it can destroy anything it comes into contact with. But it has absolutely no ability to power anything.

Except for itself. The majority of the power to run the wedge comes from an "energy siphon" effect pulling power out of the hyper wall so the ships don't need to carry the fuel to produce the vast amounts of power needed to accelerate to large fractions of the speed of light.

But apparently they're not net energy producers and still require power from the reactor to sustain the wedge and provide acceleration; it's just a small fraction of the total power being put into raising the ship's kinetic energy.

In theory you should be able to somehow recover some of that extreme kinetic energy as a power source - but the Honorverse doesn't seem to.


OTOH sail, while within a grav wave, do produce some amount of net energy, which is why you can dial down, or even turn off, your reactor and pull power to run the ship systems from the sails. (It doesn't seem to be a huge amount of net energy -- and most skippers, and certainly warship captains, aren't going to fully shut down their reactor. They'll want it at least trickling over and ready to quickly ramp up and take the load should some emergency occur or you need to dive out of hyper unexpectedly)


But the mechanics of how electricity is extracted from the fusion reactors? Well that's just never, to the best of my recollection, described. (The basic mechanism of how the fusion is achieved, sure that's mentioned, but not how electricity is extracted from it after it fuses)