Draw Power and Lightning/Electricity

[sir_pudding]

Originally Posted by Fred Brackin

As I have recently started a campaign somehwhat whimsically titled Return To Eberron II:Die Harder my refresher cramming enables me to tell you that Conduit Stones are described byt not proced in the Eberron corebook.

Yeah, I see that page 271. Annoying it doesn't even give a CL or the aura school. I wonder if that's errata.

They are also listed in the Wondrous section rather than one of the Shard sections.

Well that makes sense, since as far as I can they aren't shard items. The Elemental is bound onto the train, not the tracks.

What I can tell you is that Ve2 rated mag-lev track at $4 million a mile at TL7, $2 million at TL8 and $1 m,illion at TL9.

I wouldn't use any figure (in universal 4e $) for lightning rail costs higher than the TL9 numbers. The conomics of passenger rail are already dubious enough and what is probably the lower Starting Wealth of Eberron's TL4+whatever^ isn't going to help.

Eberron magitech produced at large scale is going to need to cost about the same as the equicvalent normal machinery and that's how I'd price it..

Let's see:
Givens:
House Orien charges 5sp per mile for a ticket.
There's one stone per 5 feet, so 1056 in a mile.
The couch costs 58,000gp and can tow an unspecified number of passenger cars with 200 people in each.

Now for the educated guesses.
Assume a average lightning rail couch hauls 3 passenger cars with an expected load of 70% of capacity for 420 passengers.The average one mile stretch of track probably sees two trains daily (there are tracks across some of the more sparsely inhabited parts of Khorvaire). Upkeep on the rail system is 10%, they expect 10% in profits, and they expect to break even on startup costs in 10 years.

A significant portion of the cost of the couch must be the Khyber shard, Lightning Reins (8,000gp), and the elemental binding itself. Therefore the other cars must be much less expensive (the only magical part being the conductor stones we are trying to figure out the cost of). Let's assume that whole train (with couch, passenger, and cargo cars) is 200,000 gp.

So that average stretch of track sees 336gp worth of passenger traffic each day. Lets say that cargo earns them an addition 300 gp for a total of 636 gp daily in earnings. In ten years that's 2,136,960 gp (the Eberron year is only 336 days) less 10% upkeep and 10% profit is 1,709,568 gp, less 400,000 gp for two trains is 1,309,568 gp for a mile of track. Assume that at least 25% is land-use rights, construction and the other physical components of the track. That leaves 982,176 gp for 1056 stones at 930 gp per stone.

Wow, that's a lot of guessing but it seems reasonable. If there are harder numbers somewhere for this stuff, I couldn't find it, (but I don't have Dragonmarked handy and there might be more in there).

We''ve got to be careful though or we'll drag Bill Stoddard into this and he'll tell us that since Sharn has dinner theaters that makes it a TL7 equivalent. :)

I seriously doubt that Bill has more than just heard of Eberron.

[whswhs]

Originally Posted by sir_pudding

I seriously doubt that Bill has more than just heard of Eberron.

Barely even that. It's D&D, isn't it? I haven't paid serious attention to D&D since 1977.

Bill Stoddard

[Raekai]

Originally Posted by sir_pudding

Yeah, I see that page 271. Annoying it doesn't even give a CL or the aura school. I wonder if that's errata.

Well that makes sense, since as far as I can they aren't shard items. The Elemental is bound onto the train, not the tracks.

Let's see:
Givens:
House Orien charges 5sp per mile for a ticket.
There's one stone per 5 feet, so 1056 in a mile.
The couch costs 58,000gp and can tow an unspecified number of passenger cars with 200 people in each.

Now for the educated guesses.
Assume a average lightning rail couch hauls 3 passenger cars with an expected load of 70% of capacity for 420 passengers.The average one mile stretch of track probably sees two trains daily (there are tracks across some of the more sparsely inhabited parts of Khorvaire). Upkeep on the rail system is 10%, they expect 10% in profits, and they expect to break even on startup costs in 10 years.

A significant portion of the cost of the couch must be the Khyber shard, Lightning Reins (8,000gp), and the elemental binding itself. Therefore the other cars must be much less expensive (the only magical part being the conductor stones we are trying to figure out the cost of). Let's assume that whole train (with couch, passenger, and cargo cars) is 200,000 gp.

So that average stretch of track sees 336gp worth of passenger traffic each day. Lets say that cargo earns them an addition 300 gp for a total of 636 gp daily in earnings. In ten years that's 2,136,960 gp (the Eberron year is only 336 days) less 10% upkeep and 10% profit is 1,709,568 gp, less 400,000 gp for two trains is 1,309,568 gp for a mile of track. Assume that at least 25% is land-use rights, construction and the other physical components of the track. That leaves 982,176 gp for 1056 stones at 930 gp per stone.

Wow, that's a lot of guessing but it seems reasonable. If there are harder numbers somewhere for this stuff, I couldn't find it, (but I don't have Dragonmarked handy and there might be more in there).

I seriously doubt that Bill has more than just heard of Eberron.

This. This is the kind of answer that I came here looking for. I want to sincerely thank you for all of the effort you put into that. And don't even give me "Oh, well it only took a couple of minutes." A minute. Fifteen. Whatever. Thank you so much.

[William]

Although the idea of a GURPS mage using a lightning strike as a source for Draw Power is so ridiculo-cool that now I want to work out how it might be done. (I know that harvesting lightning energy with technology is realistically impossible, but if Frankenstein can do it, by God so can I.)

According to Wikipedia, the average peak power output of a stroke of lightning is a terawatt (10^12 W), with the whole stroke lasting 30 to 90 microseconds, giving us

1e12 J/s * 9e-5 s * 1 360000 FP/J = 250 FP

for a strong strike, or about half that if we pretend that the power ramps up and down linearly, so 42 to 125 FP.

Unfortunately, the primary limitation on Draw Power is HT; assuming Magery 3, HT 9/4 = 1e6 MW gives HT = 4.4e5. Which, no, even if you have a ridiculously large circle of mages. (We have really high wattage, but it doesn't last anywhere near a second.) So basically we need surge protection, but some way to keep the energy running around long enough to draw it.

-----

Catch Lightning: Hard technique
Prerequisite: Draw Power and Catch Missiles; Default: lower of prerequisite skills-5; cannot exceed lower of prerequisite skills

You may use natural lightning strikes safely as sources of power for spells! In order to do so, you must have a spell ready but not cast -- therefore, this technique cannot be used to power Enchantment spells.

You cast and maintain Draw Power, awaiting a lightning strike. When it occurs, roll your Catch Missile skill. If this fails, you take the lightning stroke as a standard attack. If you succeed, the stroke provides 30+1d6x15 FP. (Particularly strong or weak storms may provide better or worse amounts of power.) You may then parcel this energy out at any rate you desire into the spell you had waiting, and only that spell, at a maximum rate of the FP you could safely draw with the Draw Power spell.

This technique could reasonably be used with other sources, such as laser weaponry or the kinetic energy of bullets, but a different technique would be necessary for each form of missile. (If a technique exists to draw energy from predictable missiles, and it could be used to power Quick & Dirty enchantment, then high-power enchantment would become much easier. This might suit a magic-as-technology setting.)

-----

If that doesn't tickle your fancy, then we'd have to come up with a new spell.

First off, Resist Lightning gives absolute immunity to electricity, which is probably a plus here. I'd also suggest Draw Power (and maybe Catch Missile?) as prerequisites. Now, since lightning is unpredictable, you would want the spell Delayed to trigger on a lightning strike; let's say that that's also a prerequisite. Unfortunately, you can't Delay or Link your target spell -- Delay and Link require that energy costs be paid at the time of casting. So let's make our new spell a Meta spell of the linking type.

A "Catch Lightning" spell would then, I think, function as follows:

Catch Lightning (VH)
Special
Meta, Technology, and Weather Colleges

You cast a spell with a special form of Delay that allows the cost to be paid upon a trigger when energy is available -- in this case, a natural lightning strike, which usually provides 30+1d6x15FP. The energy is immediately funneled into the target spell, which is then cast; any excess is lost.

While this spell is waiting, you have three spells counted as "on": Catch Lightning, and a delayed Resist Lightning and the target spell. When the spell activates, you immediately receive the benefits of a Resist Lightning spell and may choose to maintain it if you desire.

Duration: 2 hours
Time to cast: 10 seconds plus casting time for target spell
Costs: 6 to cast, 6 to maintain.
Prerequisites: Resist Lightning, Draw Power, Link

[vierasmarius]

Originally Posted by William

Catch Lightning (VH)
Special
Meta, Technology, and Weather Colleges

You cast a spell with a special form of Delay that allows the cost to be paid upon a trigger when energy is available -- in this case, a natural lightning strike, which usually provides 30+1d6x15FP. The energy is immediately funneled into the target spell, which is then cast; any excess is lost.

While this spell is waiting, you have three spells counted as "on": Catch Lightning, and a delayed Resist Lightning and the target spell. When the spell activates, you immediately receive the benefits of a Resist Lightning spell and may choose to maintain it if you desire.

Duration: 2 hours
Time to cast: 10 seconds plus casting time for target spell
Costs: 6 to cast, 6 to maintain.
Prerequisites: Resist Lightning, Draw Power, Link

Interesting spell. The energy provided by the lightning strike is pretty random though. What happens if it's not sufficient to cast the readied spell? Does it just fizzle? Or can the mage "tweak" it during casting, adjusting its magnitude (Area, dice of damage, etc) to match the available energy?

I could see potential abuse when combined with the Weather college. You of course wouldn't be able to draw power from magical lightning (from the general prohibition against using magical fuel sources) but you might use Storm to create natural lightning.

[sir_pudding]

Originally Posted by Raekai

This. This is the kind of answer that I came here looking for. I want to sincerely thank you for all of the effort you put into that. And don't even give me "Oh, well it only took a couple of minutes." A minute. Fifteen. Whatever. Thank you so much.

You might want to double check that. I'm really surprised Anthony or Bill come by to tell me that I've got the economics of railroads all bassakwards.

[Anthony]

Originally Posted by sir_pudding

You might want to double check that. I'm really surprised Anthony or Bill come by to tell me that I've got the economics of railroads all bassakwards.

Eh. The estimates for revenue are totally random (we have very little idea of D&D basic economics), and it's probably a bad idea to assume that lightning rails are mostly funded by passengers (rather than freight), but beyond that the way you calculated seems plausible enough.

[sir_pudding]

Originally Posted by Anthony

Eh. The estimates for revenue are totally random (we have very little idea of D&D basic economics),

Can you guess less randomly?

and it's probably a bad idea to assume that lightning rails are mostly funded by passengers (rather than freight)

We don't have freight rates, and I assumed that passenger service is more expensive than freight service (based on the fact that in real life that seems to be the case), but I could be wrong. How much more revenue do you suppose the freight generates relative to the passenger revenue.

[Raekai]

Originally Posted by sir_pudding

You might want to double check that. I'm really surprised Anthony or Bill come by to tell me that I've got the economics of railroads all bassakwards.

My point is that you went through the ideas like to that give a basic idea of how much something like that would cost, and even if it's really off, it is still a starting point.

Originally Posted by William

Catch Lightning (VH)
Special
Meta, Technology, and Weather Colleges

You cast a spell with a special form of Delay that allows the cost to be paid upon a trigger when energy is available -- in this case, a natural lightning strike, which usually provides 30+1d6x15FP. The energy is immediately funneled into the target spell, which is then cast; any excess is lost.

While this spell is waiting, you have three spells counted as "on": Catch Lightning, and a delayed Resist Lightning and the target spell. When the spell activates, you immediately receive the benefits of a Resist Lightning spell and may choose to maintain it if you desire.

Duration: 2 hours
Time to cast: 10 seconds plus casting time for target spell
Costs: 6 to cast, 6 to maintain.
Prerequisites: Resist Lightning, Draw Power, Link

Originally Posted by vierasmarius

Interesting spell. The energy provided by the lightning strike is pretty random though. What happens if it's not sufficient to cast the readied spell? Does it just fizzle? Or can the mage "tweak" it during casting, adjusting its magnitude (Area, dice of damage, etc) to match the available energy?

I could see potential abuse when combined with the Weather college. You of course wouldn't be able to draw power from magical lightning (from the general prohibition against using magical fuel sources) but you might use Storm to create natural lightning.

That spell is amazing, and seems to be just what I was looking for. At the prerequisite costs a spell like that is going to have, it doesn't look like it will be too easily abused for the campaign I'm in. However, the question does stand about if the spell doesn't meet the needed cost.

Also, I'd like to request a second spell. Maybe something like Store Energy where I can take the fatigue drawn from this spell and it can be contained in some sort of object. Of course, it wouldn't stay like Manastone, but would rapidly deteriorate. Maybe it would lose 1FP/Minute. I dunno. That idea is pretty unbalanced, but if you could make something like that work, I'd love to see it!

[sir_pudding]

Originally Posted by Raekai

My point is that you went through the ideas like to that give a basic idea of how much something like that would cost, and even if it's really off, it is still a starting point.

I think I'd just round up to 1000gp per stone (which seems like a reasonable cost compared to other Wondrous Items of similar utility). I'm not sure how much they weigh. It can't be that much since a rail car needs be able to carry one per 5ft of length. On the other the railways probably use ones that can't be easily stolen. Maybe they weigh 5 lbs, but the installed ones are cemented into place or something?

Of course there is a problem with converting gp to GURPS $.