[3.5] The Perpetual Generator (Catgirl killers, unite!)

[WhatThePhysics]

Removed by author.

[ericgrau]

The short answer is that you'll get 1-4 megawatts from a steam plant. You'll need a large body of water such as a lake or river, construction materials, labor and some engineering, that's all.

Though if you're allowed a continuous item of creation, you could have a continuous item of whatever the heck you want. Normally the DM isn't supposed to ok such things b/c they aren't equal to existing items. That's where a self-resetting traps to manifest the power typically come in... so you can have something technically RAW legal without a rule that specifically requires DM approval and that recommends against craziness. Still silly though.

[Malcador]

How does a continuous item of Psionic Minor Creation work? That's not a power you think of in that context.

What do you mean by "useful work"? If you just want to exert forces on objects, there are much simpler ways to do that, like a use-activated item of telekinetic force. In real life, you usually want a generator that produces electricity (which can be created in D&D by pouring an infinite supply of any fluid over a turbine); in your steampunk setting, you probably have something else in mind.

Keep in mind that most player characters, especially spellcasters and manifesters, can already do more work in a day than they consume in calories. When the laws of thermodynamics are being violated as a side effect of day-to-day activity (if the setting had anything like the laws of thermodynamics to begin with), perpetual motion isn't particularly interesting. At this point, the question is not "how do I get a free lunch?", it's "what's the best lunch I can get for free?".

If you want to do more research into this or similar topics, you might look up the "tippyverse", a setting based on analysis of the effects that widespread magic use has on typical fantasy environments.

[Alent]

In this same vein, a level 3 air domain DMM persist cleric casting Windwall under a vertical wind turbine has the potential to generate a massive amount of energy, 24 hours at a time.

[Alent]

I probably should have clarified this in the OP, but the setting will be using E6 rules. So, I'm afraid that high-level metamagic, and other powerful effects, are beyond the scope of this topic. :smallsmile:

...

@Norren: See the beginning of this post. :smallsmile:

EDIT: Now that I think about it, you raise a fair point with Wind Wall, as it's feasible to make a magic item with a continuous version of it. Unfortunately, it'd be far too expensive, which is why I'm adverse to using it as the primary power source of the setting. However, if the generators I described in the OP are just as/more expensive, it'd definitely be a more efficient alternative.

Well, a human cleric aiming for nothing else could have Divine Metamagic at level 3, and just burn turn attempts, but I get the gist of what you're saying.

A resetting trap is dirt cheap, assuming a 3rd level cleric provides the spell, 3000 gp, 240 xp, lasts 3 turns, give it an automatic mechanical reset and a cam mechanism to trigger it every 3 turns.

The wood is effectively free with a friendly druid to provide plant growth + Woodshape. Toss on a casting of Ironwood for structural integrity if that's an issue, grease traps provide frictionless bearings.

Level 1~3 magic is severely underrated.

Edit: Actually, Ironwood might be outside anyone's reach in an E6 campaign, being a level 6 spell, now that I think about it. Isn't necessary, I just like more durable materials when bringing engineering into my D&D.

[Tarlek Flamehai]

What is E6? And does it belong in the D&D 3e/3.5e/d20 area or should it be in the Roleplaying Games area?

[Jack_Simth]

What is E6? And does it belong in the D&D 3e/3.5e/d20 area or should it be in the Roleplaying Games area?
A variant of D&D 3.X where you have a level cap of 6, with some caveats. So yeah, putting it here is probably fine.

[weckar]

How would it be any better, for energy, than a continuous item of any electricity spell?

[Segev]

How would it be any better, for energy, than a continuous item of any electricity spell?

It is rather difficult - not impossible, I'm sure, but difficult - to calculate how many watts are actually produced by various electricity spells, because their behaviors are more cinematic than consistent with any one wattage, even with the same CL and everything.

Personally, I am amused by the undead power generator. Get one of those old slave- or mule-driven mills that have a living creature push them around in circles, and tie it to a dynamo. Undead don't get tired or bored, so just order them to push it around in a circle. It's not the most efficient in terms of space or material, perhaps, but each one, once set up, is free energy save for any maintenance cost to the machinery.

[Alent]

Those are good suggestions, but I feel that some of it relies on magic that's much higher than the setting baseline. Not that I don't mind the ideas, of course! It's great material for plots that will involve high mages and zany inventions. :smallsmile:

More knowledge about the setting might help. The spells, psionic powers, and traps so far have been core, but if your setting selectively omits certain options or considers certain uses of them outside the realm of inventors, that affects options. I kind of want to go looking in splats for other options. There's crazy stuff like a dragon magazine spell to create living spell oozes. Imagine how much easier this would be with a living prestidigitation you could cut in half every time you need another prestidigitation or grease spell.

In the vein of what Segev was thinking with Undead, Some of the Golems sport Breath Weapon (Steam). Between the Undead mulemill machine, and Golems in steam reservoirs, you have plenty of options for Steampunk mayhem without active magic.

I've done quite a few thought exercises like this since my group has a mad-maxish post-apocalypse steampunk campaign setting that we use, and I'm building another campaign for it to run soon. It could be very fun to compare steampunk notes. (Mine isn't E6, but we've discovered that Lv 3~8 seems to be the sweet spot for the group, so it will be somewhat similar.)


Back on topic, wouldn't Darkwood serve as a more suitable material? With half the weight, darkwood turbines would wear down more slowly. Rarity of said wood might be a problem, though, but it's definitely more accessible than Ironwood. Regardless, I'm skeptical of Wind Wall being able to efficiently power small-scale machinery via turbines, or do so without producing a rather inconvenient air current.

Wear is a strange concept by 3.5 rules, I don't think it has any rules for it at all. Even if your machine does wear, Mending is a cantrip and should be part of base maintenance, Make Whole comes out of cleric's second level spells and does a little more. I personally am fond of the Pathfinder version of Mending, since it makes fixing objects make more sense by 3.5 rules. (They don't wear... they take HP damage, and PF mending restores 1+1d4 HP! )

Rust isn't even an issue this way, unless it's magical rust. The extra durability of good material is to userproof it. Half of the people in my group think barbarians, fighters and monks trying to fix things with violence is proper. In general, people do stupid, passive aggressive, damaging things to technology. :smallannoyed:

As far as Windwall, it has a set range and space it occupies, and it doesn't extend outside of it. Being a wall spell limits the upper scale limit. (Control Winds, for example, would have consequences, tho'.)


On the subject of turbines, I'm curious as to how cost efficient it would be to make Wind Wall-powered propellers. While Agitator-powered airships might not be feasible, a magic VTOL might not be out of the question! If we throw Levitate into the mix, we could increase maneuverability, and also cut down on the number of propellers needed.

Well, Wind Wall is a stationary spell. The viability of it would be based on if a DM ruling that the windwall cast on a surface stays on that surface even if the surface is moving.

Levitate could get expensive. Out of box you're looking at a 3 minute duration and the caster controls levitation. If a trap is providing the levitation, the levitation is set at creation. Psionic levitate actually works better here with 10m/lv, but stinks. (Literally! Why is there an Olfactory display!?) There's also an inconvenient weight limit on levitating things.

I don't know enough about psionics to have a feel for that side's item usage/pricing/etc. It's on my "to learn" list... but that's a big queue.

If you're looking at a dirigible, I would look to prestidigitation and/or outrageous alchemy. Have it keep your lift cells hydrogen-proof, use hydrogen, or make a lighter than air liquid via alchemy's "Spell like" clause.

The best Dirigible option would be a Wall of Force envelope followed by magically removing all the matter inside the Wall of Force, for Void Lift. But that's a little above your play options. (Although theoretically you could always find a way to get Riverine, I guess.)


Going back to the Vegetable Matter Agitator, perhaps it could be scaled down to efficiently power mobile, metallic machinery? As with the turbines, Grease would be used to keep everything oiled, so there's no worry there. For cooling, it could have traps/items of Prestidigitation, Energy Ray (Cold), and similar effects. I'm thinking we could avoid water-based effects, to reduce the formation of rust.

Prestidigitation can protect an object from lava by giving it DR 2\fire, you could always use that solution on your casing for the agitator. It also can rustproof things by keeping them clean, so... yeah... Least wish breaks science again. :smallamused:

The Agitator's heat could even be a feature. Put an oven on top of it. :smallwink:

[ericgrau]

@ericgrau: So, unless we're using it near a massive heat sink, spamming dozens of magic items that could cool it down, or significantly scaling its output down, one of these generators are unfeasible? I feared that that might be the case, but I wasn't quite sure. :smalleek:
Oh you wanted portable power not just a power plant? Well the generator may be quite huge so you'd need quite the cart. And yes some kind of portable heat dump. About 15 gallons of water per second should do it.

And undead turning a big wheel is good for about 100 watts a corpse if it moves as fast as a walking person. A hustle or run and a lot of force for strenuous exercise could do as much as 8 times as much, 15 times with a good strength. Maybe ogre skeletons for much more than that even, though it also costs more HD.

Wind can work but it's pretty weak.